Next Article in Journal / Special Issue
The Economics of Health Damage and Adaptation to Climate Change in Europe: A Review of the Conventional and Grey Literature
Previous Article in Journal
A Sequential Method of Detecting Abrupt Changes in the Correlation Coefficient and Its Application to Bering Sea Climate
Previous Article in Special Issue
Air Temperature and Death Rates in the Continental U.S., 1968–2013
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:

Emerging Environmental and Weather Challenges in Outdoor Sports

Institute of Sports Sciences, Department of Physiology, Faculty of Biology and Medicine, University of Lausanne, Building Geopolis, Campus Dorigny, Lausanne CH-1015, Switzerland
Author to whom correspondence should be addressed.
Climate 2015, 3(3), 492-521;
Submission received: 25 March 2015 / Revised: 2 July 2015 / Accepted: 6 July 2015 / Published: 14 July 2015
(This article belongs to the Special Issue Climate Impacts on Health)


Given the climatic changes around the world and the growing outdoor sports participation, existing guidelines and recommendations for exercising in naturally challenging environments such as heat, cold or altitude, exhibit potential shortcomings. Continuous efforts from sport sciences and exercise physiology communities aim at minimizing the risks of environmental-related illnesses during outdoor sports practices. Despite this, the use of simple weather indices does not permit an accurate estimation of the likelihood of facing thermal illnesses. This provides a critical foundation to modify available human comfort modeling and to integrate bio-meteorological data in order to improve the current guidelines. Although it requires further refinement, there is no doubt that standardizing the recently developed Universal Thermal Climate Index approach and its application in the field of sport sciences and exercise physiology may help to improve the appropriateness of the current guidelines for outdoor, recreational and competitive sports participation. This review first summarizes the main environmental-related risk factors that are susceptible to increase with recent climate changes when exercising outside and offers recommendations to combat them appropriately. Secondly, we briefly address the recent development of thermal stress models to assess the thermal comfort and physiological responses when practicing outdoor activities in challenging environments.

1. Introduction

1.1. Practicing Sport Activities in a Challenging Environment?

It is popularly perceived that regular physical activity reduces the risk of developing chronic diseases (i.e., cardiovascular, overweight and obesity, type 2 diabetes, hypertension and certain types of cancers [1,2]) and improves psychological well-being [3,4]. In this vein, outdoor sports practice offers a preeminent gateway to a healthy active lifestyle [2,5], and is undergoing unprecedented popularity (e.g., +26% increase in USA outdoor runners population over 5 years from 2007 to 2012, leading to >53 millions of practitioners) among recreational and competitive individuals. This is notably the case for activities such as running/jogging, triathlon (traditional/road, non-traditional off-road), marathon, adventure racing, trail running, trekking/climbing (traditional/ice/mountaineering), biking (road, mountain, BMX), skating (in-line and on-ice), skiing (cross-country, biathlon, alpine/downhill; including snowboarding), swimming, windsurfing and surfing (including wakeboarding, stand up paddling), scuba diving/snorkeling, kayaking and rafting, team sports (e.g., soccer, ice-hockey) and tennis. Additionally, acceleration in sport technology development (e.g., specific clothing, global positioning system) facilitates practice of these outdoor activities without any specific pre-conditioning.
Outdoor sports participants may experience exertional hyperthermia (i.e., core temperature >39 °C), when practicing in warm-to-hot ambient conditions, or hypothermia (i.e., core temperature <35 °C) in cold or cool-windy environments. Thus, when exposed to environmental thermal stress, the likelihood of practitioners facing health risks increases. According to the laws of thermodynamics, the body loses heat when environmental temperatures are lower and vice versa [6]. Heat transfer in either direction occurs by convection (sensible heat flux), conduction (contact with solids), evaporation (latent heat flux), radiation (long- and short-wave) and respiration (latent and sensible) [7]. Environmental factors related to heat transfer are a combination of air temperature, wind speed, relative humidity and radiation. In addition, there are individual factors (e.g., age, gender, morphology, fitness) [8,9] which can interfere with physiological thermoregulation [6].
Physiological responses to exercise in challenging environments vary substantially among participants, with also periodic reports of severe or, albeit rare, near-catastrophic incidents of environment-related illnesses in a restricted number of practitioners. Even though compliance with heat-, cold- and altitude-related guidelines (e.g., use of fixed Wet Bulb Globe Temperature (WBGT) cut-offs to decide whether or not to suspend football or tennis matches) [10,11,12,13,14] would not guarantee full protection it will, however, reduce potential risks for most individuals.

1.2. Climate Change Consequences on Outdoor Sports Practice

Noticeable climatic changes occur around the world, as evidenced for instance by a global annual average temperature increase of ~1 °C over the last century, also majoring the number of episodes of extremes of heat and heavy precipitations. As such, it becomes a priority, not only to re-emphasize current but also, to provide additional recommendations in order to address and minimize risks of environmentally prompted illnesses and in extreme situations deaths due to outdoor sports participation. Weather forecasts in many parts of the world now routinely provide detailed information on levels of ozone and particulate air pollutants, of pollen and of exposure to ultraviolet radiation (UVR), along with warnings of when high or low temperatures may become hazardous to health. The appropriateness of outdoor environments for sport activities practice has hitherto been mostly assessed in terms of air temperature and one of a variety of expressions for humidity (e.g., relative humidity) for warm conditions, air temperature combined with air velocity for cold conditions [7], and other basic weather parameters (i.e., vapor pressure, solar and thermal radiation), all being easily recorded from simple and rather inexpensive instruments. The influence of other meteorological factors (e.g., atmospheric pressure, precipitation and cloud cover) on outdoor sports performance is, however, often disregarded. Moreover, internal metabolic heat production [15], which closely depends on the exercise type, duration and intensity, as well as the aforementioned individual parameters and the clothing insulation are likely introducing large errors into any prediction of any adverse weather effect [16]. Thus, accurately modeling thermal stress requires consideration of the physical environment along with the physiological and psychological attributes of practitioners [17,18]. This has led to the development of various indices (e.g., WBGT or Modified discomfort index) attempting to describe thermal stress (see [19]). However, after nearly 50 years of experience with heat budget modeling (i.e., heat exchange between the human body and the thermal environment [9]) and easy access to both computational power and meteorological data, it is surprising that the use of simplistic indices such as WBGT [20] continue to be widely recommended by major sports governing bodies (IOC, FIFA) [13]. A better understanding on thermal balance regulation during exercise in various outdoor environmental conditions is vital in furthering the validity of available models and improving outdoor recreational and competitive settings.
Comprehensive reviews have been published on thermal strain when exercising in the heat [12,21], in cold [10,22], at altitude [10]; on specific environmental-related risks (i.e., pollution [23], allergen [24], UVR [25]); as well as on mechanisms of thermoregulation through sweating [26], clothing properties and metabolic heat production [27]. This has led to comparisons of selected simple thermal indices [19] and more complex approaches (see [28,29]). However, to our knowledge, no appraisal has yet focused on an integrated view of the various environmental-related parameters for outdoor sports participation, with special reference to global warming. Therefore, the aims of this review are twofold: first, we summarize the major environmental-related risk factors (and associated challenges) that are susceptible to increase with recent change in climate when practicing outdoor sport activities. In addition, we re-emphasize general recommendations to prevent the associated risks. Secondly, we briefly address the recent development of thermal stress models to assess the thermal comfort and physiological responses when exercising outside in challenging environments.

2. Environmental-Related Risk Factors

2.1. Heat

Global warming leads to an increased incidence of heat waves (i.e., extended periods of extreme high temperatures), which substantially deteriorates human health [30,31,32]. While elderly—and to a lower extent, children—are primarily affected by heat stress during their outdoor sport practice, other outdoor recreational and competitive individuals may also be at risk.
As intense or prolonged exercise is completed in both cool (e.g., 8 °C–18 °C) [33,34,35] and hot/humid ambient conditions [36,37], the development of heat illnesses varies on a severity scale continuum [38] (mainly due to overlapping diagnostic features) ranging from mild (heat rash, syncope and cramps) to serious (heat exhaustion, injury and stroke) [12,33]. Exercise-associated muscle cramps, also called heat cramps, are painful spasms of skeletal muscles occurring in the heat [39]. Occurrence of heat cramps is more common in long distance runners [40] as well as in athletes engaged in prolonged, high-intensity sports (i.e., tennis, American football and soccer) [41,42]. The main factors thought to be responsible for the development of heat cramps are muscular fatigue, body water loss and large sweat [Na+] loss [42,43].
While exertional hyperthermia is defined as an elevation in core temperature above 39 °C [44,45,46], heat exhaustion commonly refers to a mild-to-moderate illness (i.e., inability to sustain cardiac output) occurring at moderate (>38.5 °C) to high (>40 °C) core temperatures [44,46,47]. The latter is frequently accompanied by hot skin and a dehydration state. Heat injury is a moderate-to-severe illness (i.e., injury to an organ (e.g., liver, kidney, gut, muscle)), which in most cases occurs with high core temperatures. Heat stroke is a severe illness in outdoor sport participants characterized by central nervous system dysfunction (e.g., confusion, disorientation, impaired judgment) and is usually accompanied by a core temperature above 40.5 °C. Heat stroke can be complicated by liver damage, rhabdomyolysis (breakdown of muscle tissue), widely distributed blood clotting (disseminated intravascular coagulation), water and electrolyte imbalances, and kidney failure [34,48,49,50,51].
Although any sport practitioner can sustain heat-related illnesses, a variety of factors substantially increases development risks [12]. In general, obesity (i.e., a body mass index >30 kg·m−2), low physical fitness levels, non-heat acclimatization [33,36,44,52], dehydration (i.e., elevated urine specific gravity, hematocrit, hemoglobin or serum osmolality) [52,53], with a previous history of exertional heat-related injury [43,46,54,55], sleep deprivation [54], sweat gland dysfunction, sunburn, viral illness, diarrhea, age >40 yr, male [54], Caucasian [56], are factors increasing the risk of heat-related illness. Furthermore, individuals with sickle cell trait (i.e., higher prevalence in Blacks and certain Asian populations) [57], those having genetic predisposition to malignant hyperthermia or taking certain medications (e.g., antidepressant [58]), also have increased risks during outdoor practice.

Recommendation/Heat Stress

Development of cardiorespiratory fitness (e.g., training at intensities ranging between 70%–80% of maximal heart rate, 2–3 times a week for 30–45 min [59]), implementation of preventive countermeasures including pre-cooling (external (application) and internal (ingestion) of cold modalities including air, water and/or ice, separately or in combination [60]), heat acclimatization (exercising 60–90 min, every second day in hot conditions to induce profuse sweating and core temperature elevation (>1 °C), for at least one but ideally two weeks; [61]) and individualized hydration strategies (starting practice euhydrated, maintenance of fluid balance; limiting body weight loss < 2%; [12]) and salt balance (consuming a solution containing 0.5–0.7 g·L−1 of sodium; [12]) would reduce the risk of heat-related illnesses [12,62]. Taking into consideration local weather data, training and competition should be preferably scheduled during the cooler hours of the day (e.g., early morning) during particularly hot (>30 °C) and humid (80% RH) months, with extended recovery periods (3–6 h) between practice sessions [12]. Near-maximal exertion should be avoided before acquired physical fitness and heat acclimatization (increased sweating and skin blood flow responses, plasma volume expansion and hence improved cardiovascular function) are sufficient to support high-intensity, long-duration exercise training or competition [63,64]. Practically, acclimatization requires gradually increasing the duration and intensity of exercise during the initial days (~3–5 days) of heat exposure [65], while exercising heart rate being the most accurate means of judging exercise intensity. Encouraged behaviors include (i) unlimited fluid access (although hydration recommendations still needs to be agreed on [66]); (ii) longer and/or more frequent breaks into practice facilitating heat dissipation, shorter exercise times decreasing heat production; and/or (iii) postponing training sessions or competition when environmental risks are high [12]. Removal of extra clothing limiting sweating would also reduce heat storage and improve heat balance.

2.2. Ultraviolet (Exposure)

Outdoor sport training sessions and competitions usually take place during the peak hours of UVR, i.e., between 10 a.m. and 4 p.m. [67]. Reportedly, small doses of UVR from the sun help the body to produce vitamin D [68]. However, too intense, intermittent- and total cumulative-exposure to UVR have been associated with the development of both melanoma and non-melanoma skin cancers [69,70,71], while the number of malignant melanoma cases over the last 40 years has doubled every 7–8 years [72,73]. Apart time spent outside from an early age [70,74], numerous factors predispose outdoor sport participants to UVR injury (e.g., sunburns). Firstly, by enhancing the photosensitivity of the skin, sunburn risk is increased by heat and/or exercise-induced sweat production, thereby contributing to UVR-related skin damage [70,75]. Secondly, specific environments such as altitude [76] add to the exposure risk [70]. For example, skiing for durations as short as 6 min is enough to reach “minimal erythema dose” level [77], as UVR reflection is received both from the sky and the snow (the ground) [76,78]. In many aquatic sports, water is also reflecting a significant portion of UVR [70]. Skin areas presenting the highest risk for UVR exposure include the face, neck, hands, legs, and feet (dorsal); moderate risk areas are the thorax, thighs, arms, and forearms. Finally, initial erythema (i.e., skin redness caused by congestion of the capillaries in the lower layers of the skin) becomes evident typically 3 to 5 h after significant sun exposure (e.g., midday during 15–30 min for an individual with fair skin), and reaches maximum severity 12 to 24 h post-exposure before gradually resorbing over the next 72 h [79].


Awareness of appropriate attitudes to face sun exposure is paramount to limit risks of skin cancer development in outdoor sport participants. The reality, however, is that sunscreen preparation and/or solar UVR protective textiles are currently underused [80] and their use is even forbidden by some official competition rules and regulations. For instance, it was not allowed to apply sunscreen on the thighs and shoulders to mark competition numbers onto the skin during the Hawaii ironman triathlon [81], while the use of hats and sunglasses is forbidden for field hockey and soccer players [82]. Such restrictions result from a lack of information related to the preventive effectiveness of sunscreen. While several educational interventions can increase adherence to sun safety behaviors and practices in coaches and their athletes [83,84,85], most of previous sun protection prevention programs [83,84,86] have demonstrated low success rates. Referring to the Global Solar UV Index would help to handle UVR risks more efficiently. Recommendations for reducing exposure to UVR generally include: (i) avoiding sun (especially during the peak UV exposure hours; i.e., between 10 a.m. and 4 p.m.) and using shaded areas not only for athletes but also those who are not actively practicing; (ii) wearing protective clothing (i.e., long pants, long-sleeves shirts, hats and sunglasses); (iii) applying sunscreen preparations (i.e., sun protection factor 15+). One practical tip is the establishment of visual cues around locker rooms, reminding athletes to apply sunscreen. Furthermore, developing different sunscreens that are specific to competition needs of each individual athlete would undoubtedly enhance compliance. Finally, annual pre-season dermatologic screenings are valuable prevention initiatives.

2.3. Lightning and Severe Wind

Although rare, participants engaged in mountainous ultramarathons, for instance “Ultra trail du Mont Blanc, Tor des Géants or Hard Rock”, may suffer from lightning strikes [87,88], whose timing occurrence (i.e., afternoons during summer months) often corresponds with the peak of sport participation on possible remote locations. Lightning could potentially lead to lethal injuries [89,90] through its electrical current, heat production, and concussive force [91]. Among the different types of lightning contacts [87,92], side flash (i.e., lightning hitting an object before jumping to the nearby individual), for instance standing under a tree for protection in a storm, is the most frequent [93]. Other types include direct strike (i.e., lightning hitting an individual) and contact (i.e., lightning hitting an object in contact with an individual). Lightning injuries comprise dermatologic manifestations (e.g., Lichtenberg figures, superficial erythema and blistering, and punctuate, contact and linear first or second degree severity burns [91,92,94]) as well as musculoskeletal (multiple fractures including shoulder dislocations and cervical spine fractures [92]), cardiopulmonary (temporary cardiac or respiratory arrest, ventricular fibrillation and prolonged cardiac arrest) and neurologic (confusion, amnesia, temporary deafness or blindness, and temporary unconsciousness [91]) disorders. Among long-term squeals of lightning strikes are post-traumatic headache, sleep disorders, irritability, psychomotor impairment and sympathetic nervous system dysfunction [87,93,95,96].
Wind is a by-product of weather generally associated to thunderstorms [97]. With the exception of hurricanes, tornados or cyclones, wind is generally described as straight-line air movements, down- (i.e., horizontal downdrafts >4 km) and micro-burst (i.e., outwards winds at the earth’s surface with or without rain) and gust front (i.e., when the front of rain-cooled air collides with warmer air of the thunderstorm inflow) [97]. Severe winds generally develop prior to a thunderstorm [97]. To date, three levels of advisement for wind have been issued: advisory (i.e., sustained wind or wind gusts ranging 40–60 km·h−1 for an hour or longer), watch (i.e., range: 61–85 km·h−1) and warning (i.e., >85 km·h−1) [97]. Whereas outdoor sporting event’s officials seem to have a handle on the wind impact for optimal performance in individual sports [97], it does not seem that participant (or even spectator) safety is a major concern.

Recommendations/Lightning and Severe Wind

Before engaging in outdoor sport activities, individuals must be aware of weather reports and the possible occurrence of thunderstorms in relation to the location of their practice or competition playgrounds. When practicing, the best way to avoid lightning strikes is to use the 30 s–30 min rule [98]; which requires counting the time between seeing the lightning and hearing the thunder from the flash; a time ≤30 s requires to actively seek shelter (building or a metal-roofed automobile but not a golf car or a bus stop [91]) within 30 min. This safe location must be identified before exercise starts. Activities may resume after a 30 min period free of either last thunder or lightning flash.

2.4. Air Pollution

Air pollution is a growing environmental burden worldwide, which is thought to be the result of climate changes (hotter ambient temperatures exacerbate the harmful effects of ozone and air pollution), arising from greenhouse gas CO2 accumulation [99]. Despite this, international competitions are often organized in large cities. For instance, at the occasion of the Beijing Olympics some visiting athletes were seen wearing a mask to protect them from heavy dust and pollution. Air pollution is a heterogeneous mixture of gases (e.g., ozone, carbon monoxide, sulfur dioxide, nitrogen oxides) and air-suspended mixture of solid and liquid particles, namely particulate matter [100,101,102]. In addition to commonly reported symptoms including cough, throat irritation, chest discomfort, skin or eyes irritations, these pollutants are likely to cause a myriad of other adverse effects in urban outdoor practitioners, affecting their health substantially. This would possibly include deteriorated lung function [103,104]; increased levels of inflammatory markers and altered immune function in the pulmonary system [103,105]; myocardial infarction, stroke, atherosclerosis, bronchitis and asthma [106,107,108,109,110,111]. As ventilation rate and breathing frequency are elevated during exercise and breathing switches from a nasal to a mouth-predominance [112], this results in a large air pollution inhalation when exercising outdoors [113,114]. Furthermore, a possible link between air pollution exposure and adverse effect on cognition (e.g., via an exercise-induced decrease in human Brain-Derived Neurotrophic Factor serum concentration) has recently been highlighted (see [23,115] for details) but its effect on impaired outdoor sport performance has not been elucidated yet.

Recommendations/Air Pollution

Both animal and human researches [116,117,118] suggest that a higher fitness level might attenuate the deleterious effects of polluted air [119,120,121,122], through cardio-protective effects of physical exercise [1], potentially reducing the likelihood of air pollution-related mortality [121,122]. By practicing outdoor activities away from congested traffic and preferably in the morning (especially in summer months since elevation in ambient temperature increases air pollution-induced lung inflammation, and impairs exercise capacity [115]) will minimize the negative effect of exposure to polluted air on health. In the meantime, air quality indices (e.g., the Air Quality Index) have been developed to inform practitioners about the level of the various pollutants in the ambient air, thereby helping them to engage or not in physical activities.

2.5. Cold

More than 34 million individuals are traveling to mountainous areas every year (e.g., recreational and competition winter sports participants) and routinely face environmental challenges such as extremely cold temperatures (−1 °C per 150 m ascent) and changing ice or snow conditions [123]), thereby placing themselves at risk of cold injuries. With higher mortality rates in winter compared to summer [124,125], it is paramount to evaluate the consequences of exercising in cold conditions. Cold-weather environments include low air or water temperature (or both), strong winds, low solar radiation and often rain/water exposure, which considerably increase convective heat transfer coefficient [126,127]. Cold-related injuries can be classified into three categories: hypothermia (low core temperature, <35 °C), frostbite (freezing injuries of the extremities), and nonfreezing injuries of the extremities (for details, see [128]). Cold-induced asthma and acute cardiovascular events such as myocardial infarction [22] represent secondary outcomes. In addition, hands losing their dexterity or less sensitive fingers, impaired coordination, visual acuity, general alertness or reflexes are other negative manifestations of cold exposure. In cold environment, practitioners are more liable to make mistakes or wrong cognitive choices, as their decision-making deteriorates (e.g., rugby players dropping the ball on the coldest match days) [123], potentially increasing the risk of being injured as well. Prolonged exposition to cold environments can cause hallucinations, while the combination of cold and hypoxia exacerbate the magnitude of physiological adaptations [123]; for instance, hypoxia is known to increase cutaneous vasoconstriction during prolonged cold exposure [129]. Finally, “cold urticarial” arises during re-warming after cold exposure.
Although being more frequently observed in alpine, and some endurance or team sports [128], nonfreezing (or cold-wet injuries such as chilblains [130,131] and trenchfoot [130,131]) injuries are typically not a major concern for the great majority of athletes. This is because these injuries typically develop after at least 12 h of skin exposure to cold-wet (≤10 °C) conditions. Depending of the degree of core temperature decrease, hypothermia is classified as “mild” (35 °C to 33 °C), “moderate” (32 °C to 29 °C), and “severe” (<28 °C) [132,133]. Frostbite is a localized freezing of body tissues which occurs when tissue temperatures fall below 0 °C [134,135,136,137]. As frostbite progresses from distal to proximal and from superficial to deep tissues, the mostly exposed zones include nose, ears, cheeks-though the cornea and wrists, while even clothed hands and feet can be affected [138,139]. Similar to hypothermia, frostbite has defined stages, delineated by the depth of tissue freezing: frostnip (superficial skin <10 °C), mild (<−2 °C and extracellular ice crystals form), and severe (resulting in microvascular collapse at the arteriole and venule levels and conducting to tissue death) frostbite [132,134,135,136,137].
In all cases, individual factors modify the magnitude of the responses to cold exposure and thereby modulate the injury risk [132]. The main predisposing factors for hypothermia when exercising outdoor include health status (e.g., diabetes, hypoglycemia) [133,140], rain, wind [126], altitude, wet clothing, anthropometry (i.e., low subcutaneous body fat [141,142,143], large surface area-to-mass ratios [144]), fatigue, age, gender and ethnicity. In particular, gender differences in thermoregulatory responses during cold exposure are primarily attributable to body fat content, subcutaneous fat layer, muscle mass, and surface area-to-mass ratio [145]. Physiological and anthropometric differences also suggest 2–4 times higher frostbite risk in exercising blacks Afro-Americans compared with whites Caucasian [146,147]. Due to differences in body composition and anthropometry, children are usually at a greater risk of hypothermia than adults during outdoor practice; however, the elderly (>60 yr) also have elevated risks because their physiological and behavioral responses to cold may become blunted with age [148,149]. Finally, while physical training and level of fitness only have minor influences on thermoregulatory responses to cold [148,150], improved physical fitness allows sustaining higher metabolic rates for longer exercise durations, and may therefore contribute to the maintenance of core temperatures in the “normal range” [22].

Recommendations/Cold-Related Injuries

Cold-weather clothing protects against hypothermia and freezing injuries by reducing heat loss through the insulation provided by the clothing and the trapped air within and between clothing layers [151]. Typical cold-weather clothing when practicing outdoors consists of three layers; firstly, an inner layer (lightweight polyester or polypropylene), which is in direct contact with the skin and does not readily absorb moisture, but wicks moisture to the outer layers where it can evaporate; secondly, a middle layer (polyester fleece or wool), providing the primary insulation; thirdly, an outer layer, designed to allow moisture transfer to the air, while repelling wind and rain [22]. Hats and knit caps can be used as well to prevent heat loss from the head [152]. Practically, socks should not fit tight and constrict blood flow and shoes can be up to one size larger. Additionally, avoiding being “overdressed”, reducing the duration of a training session/competition or even canceling it, and offering warm facilities for warm-up (i.e., of sufficient duration to stimulate core temperature) or recovery routines would help mitigating cold-related injury risks. The largest occurrence of hypothermia is often when practitioners do not expect it. Finally, hypothermia is best prevented by careful monitoring of ambient temperature, wind, solar load, rain, immersion depth, and altitude when engaging in outdoor activities [153].

2.6. Altitude

In mountainous environments, barometric atmospheric pressure declines with altitude ascent above sea level. Because barometric atmospheric pressure is a function of the surface temperature [154], global warming likely increases barometric pressure at every mountain summit, thereby reducing hypoxia severity and eventually ameliorate exercise capacity (yet expected changes would not be perceptible). However, the physical and physiological effects that accompany a decline in barometric pressure can have a dramatic negative influence on prolonged-duration exercise performance (e.g., running, cross-country skiing) [155], as arterial oxygen pressure is impaired [156]. Meanwhile, air density is modified by pressure changes, which would affect the motion of the human body and/or projectiles (balls) through the air upon altitude ascent [157]. Thus, improved explosive performance (jumping, sprint running and skating) may be produced given that more energy would be available for acceleration [156].
Exercise capacity in oxygen-deprived environments not only depends on the absolute terrestrial altitude, but also on the altitude difference with the normal height of residence, as well as other environmental conditions (e.g., heat, cold; see above sections). Except for mountaineering activities, most of training/competition altitude venues are ranging between low- (500–2000 m) and moderate- (2000–3000 m) elevations [158]. Reduced oxygen availability is the starting point of a cascade of events that may eventually lead to high-altitude illnesses, the most common being acute mountain sickness (AMS). In more severe circumstances (generally occurring at altitude > 2000 m [159]) high altitude pulmonary edema (HAPE) and high altitude cerebral edema (HACE) may also occur (see [14] for details on medical care). The prevalence of such maladaptation to hypoxic stress is higher in mountain sport participants (e.g., alpinists) [91]. Nevertheless, practitioners with sickle cell trait who are heterozygous for the hemoglobin S gene and at risk for splenic infarctions even at moderate altitudes [160,161] can also face such problem, in addition to their increased risk for sudden death from exertional heat illness and rhabdomyolysis. Outside individual susceptibility [162], other factors may also increase the risk of developing high-altitude illness when exercising outdoors; those are altitude severity, rate of ascent, time of exposure, sleeping altitude, previous history of altitude illness, permanent residence at low altitude, and level of exertion while at altitude [162,163,164].


While professional athletes use a broad range of natural/simulated altitude exposure interventions to acclimatize (i.e., 3–5 days, 1–2 weeks and >2 weeks for low, moderate and high altitude performance, respectively) [165,166], most recreational winter sport participants do not have time and budget to elaborate scientifically-sounded altitude acclimatization regimens in line with their characteristics and needs. However, altitude acclimatization does not necessarily need to be rigidly planned. This implies that even informal trips to the mountains for hiking or camping during the weeks or months preceding an expedition or a competition likely may reduce the prevalence and severity of AMS symptoms [162] and enhance performance during subsequent altitude sojourns. While the scientific ground is not solid yet, it seems that acclimatization using hypobaric hypoxia could be more efficient than normobaric hypoxia [167]. Being exposed to altitudes similar to those of the upcoming sporting events during the prior weeks or months, individuals are in a better position to judge whether or not they are susceptible to face AMS. They will also be able to modify the aforementioned risk factors in order to determine what strategies work best for them to improve exercise tolerance. Generally, it is recommended to stage ascent up to 2000 m and thereafter to spend one day of acclimatization for each 300–500 m above 2000 m. Once at altitude, it is also recommended to increase water intake up to 3–5 L·day−1 to counteract water loss when breathing cold dry air (called “insensible water loss” which can reach 1–2 L·day−1), urine output, sweat loss during thermal regulation [168]. Finally, acetazolamide or glucocorticosteroid drugs (both listed as prohibited substances by the World Anti-Doping Agency) could be prescribed in non-competitive individuals to prevent or attenuate AMS symptoms.

2.7. Snow and Avalanche

Over the past 30 years, global-warming has resulted in an elevation of the heights (~100–300 m) at which the ground is permanently frozen in the Mount Everest region [169]. Additionally, because of the snow cover decline, the snow season has been shortened by ~3 weeks in reference to the early 1970s in the Northern Hemisphere [170]. However, it is not the quantity but quality of snow that is crucial for safety while skiing or practicing other emerging snow-related activities (e.g., snowshoeing). A warmer, moister atmosphere increases the risk to produce heavier or wetter snow, which also rises the density of the snowpack [170]. Altogether, at altitudes where most of ski resorts are installed, this may increase risks for avalanches, unstable seracs as well as rock falls (as a result of the permafrost alteration). The increasing incidence of avalanches fatalities (i.e., 150 deaths/year in Europe and North America) [171] comes together with the wider practice of winter sports, with backcountry/out-of-bounds skiers accounting for almost half of avalanche fatalities [172].
The avalanche fatalities literature describes asphyxia as the main cause of death, as a result of airway obstruction, mechanical chest compression, and rebreathing expired air conducting to hypercapnia and hypoxia [173]. Reportedly, the incidence of lethal and nonlethal mechanical trauma also ranges from 5% to 32% [173]. In victims buried in snow avalanches, the presence of an “air pocket, defined as any space surrounding the mouth and the nose, no matter how small, with a patent airway”, is necessary for prolonged survival from burial [174]. In this case, while initial survival is due to an effective thermoregulation, acute hypothermia takes approximately 30 min to develop [175].

Recommendations/Snow and Avalanche

In response to the increased participation and emerging out-of-bounds-related activities, many efforts have been invested in avalanche education and awareness. However, adherence to prevention and safety practices is still low, with discrepant behaviors between sports. To convey avalanche hazard, specific information bulletin are available from internet and/or most of ski resorts meteorological offices. Checking such information, including eventual discussing avalanche hazard to ski patrol, is an integral part of preventive routine practices (i.e., strategies reducing the chance to be involved in an avalanche) for individuals leaving the ski area boundaries [172]. Similarly, carrying safety gears (i.e., beacon, shovel and probe) and being properly trained to use them are also strategies increasing dramatically chances to survive an avalanche [176]. In addition to increase (e.g., S1 + DVA transceiver, Ortovox Sportartikel GmbH, Taufkirchen, Germany) or extend (e.g., AvaLung™; Black Diamond Equipment Ltd., Salt Lake City, UT, USA) survival in the case of burial, newly developed avalanche airbags (e.g., Halo 28 Jetforce avalanche airbag pack; Black Diamond Equipment Ltd., Salt Lake City, UT, USA) also prevent critical burial [176,177].

2.8. Exercise-Induced Asthma and Bronchial Hyper-Responsiveness

Development of outdoor practice may increase exposure to inhaled irritants (air pollution) and resilient airborne allergens in the spring and summer [178]. One of the most widespread types of allergy relates to the presence of allergenic pollens in the air. Along with climate changes, the total amount of pollens measured in the ambient air has grown in recent years, probably because temperature and CO2 concentrations follow a similar trend. Evidence suggests that air pollutants and anthropogenic aerosols may alter the impact of allergenic pollens by changing the amount and features of the allergens, thereby increasing human susceptibility to them [179]. In addition, practicing outdoor activities in cold ambient conditions [178] elevates the incidence of respiratory complications such as exercise-induced asthma (EIA) and bronchial hyper-responsiveness (BHR) [180]. This is generally accompanied by an increased number of granulocytes and macrophages in the lower airways [181], susceptible to increase asthma, seasonal allergy and rhinitis.
Prevalence of EIA and BHR is high in endurance sports—cross-country skiing [182,183] and biathlon and Nordic combined [183] but also cycling [184], long-distance running [178,185] and swimming [186]—as well as in explosive-based sports—figure skating [187,188], speed skating [183] and ice hockey [189] or track-and-field [185,190]. For winter sports, it is worth mentioning that cold inhaled air is recognized as the main factor responsible for airways obstruction [191]. While mechanisms of EIA and BHR are still debated [192,193], the association between the increased ventilation rate during exercise and the fluxes of heat and water developed within the airways seems prominent [194].

Recommendations/EIA and BHR

Similar prevention approaches than for air pollution could be adopted: allergic practitioners will benefit from considering pollen distribution forecasting to effectively plan their outdoor activities. However, to date, there is no dose-response threshold that has been firmly established for pollen sensitivity, where severity of symptoms also varies considerably between individuals. For example, while symptoms would occur with counts of 15 to 75 grain·m−3 per 24 h in highly sensitive individuals, levels up to 10 times greater may be required less-sensitive individuals [195,196]. In-depth clinical examination of “at risk” outdoor sports participants, with the addition of preventive medication (e.g., non-sedating antihistamines, intranasal corticosteroid spray) or immunotherapy programs is recommended [195]; i.e., especially before peak airborne allergen ripening and release in the atmosphere. To efficiently prevent EIA and BHR, outdoor exercises should be avoided during the full pollen season. When training in cold conditions, protection equipment (e.g., heat and water exchanger Lungplus, Hörby, Sweden) could also be used to convert cold incoming ambient air into a warmer and more humid breathed air.
In summary, main risks, increasing risk factors and countermeasures for different weather-related conditions in outdoor sports participants are displayed in Table 1.
Table 1. Main risks, increasing risk factors and countermeasures for different weather-related conditions in outdoor sports participants.
Table 1. Main risks, increasing risk factors and countermeasures for different weather-related conditions in outdoor sports participants.
Environmental ChallengeMain RisksIncreasing Risk FactorsSafety Measures
HeatMinor symptoms:
Dehydration state, increasing core temperature.
Major symptoms:
From moderate-to-severe heat illnesses.
Caucasian, male, age >40 yr,
Obesity (body mass index >30 kg·m−2),
Previous history of exertional heat-related injury,
Sweat gland dysfunction,
Viral illness, diarrhea, sickle cell trait, sunburn,
High humidity,
Non-heat acclimatization,
Sleep deprivation,
Low fitness levels,
Excessive heat exposure (warm-up).
Weather forecasting,
Heat acclimatization,
Endurance training,
Remove extra clothing,
Practice in cooler periods, with shorter exercise time and longer/more frequent recovery periods (shaded areas),
Hydration/salt balance strategies; start exercise euhydrated and with unlimited fluid access.
UVR-related skin damage,
Melanoma and non-melanoma skin cancers.
Accumulation of chlorofluorocarbons and other industrial chemicals in the atmosphere,
Reflective environments (snow, water),
Heat and/or exercise-induced sweat production.
Solar UV Index forecasting,
Wear protective clothing,
Apply sunscreen protection factor 15+,
Avoid peak UV exposure hours and use shaded areas.
Dermatologic manifestations,
Musculoskeletal, cardiopulmonary and neurologic disorders
Post-traumatic headache, sleep disorders, irritability, psychomotor impairment and sympathetic nervous system dysfunction.
Weather forecasting,
Identify safe location before practice.
Air pollutionMinor symptoms :
Cough, throat irritation, chest discomfort, skin or eyes irritations.
Major symptoms:
Deteriorated lung function, increased levels of inflammatory markers and altered immune function in the pulmonary system, myocardial infarction, stroke, atherosclerosis, bronchitis, asthma, cardiovascular and cerebrovascular diseases and adverse effect on cognition.
Hotter ambient temperatures,
Accumulation of greenhouse gas CO2,
Urban environment.
In addition to heat countermeasures:
Air quality indices forecasting,
Practice activities away from congested traffic and preferably in the morning.
Wear a mask.
Hypothermia, frostbite and nonfreezing injuries,
Cold-induced asthma and acute cardiovascular events such as myocardial infarction,
Cognitive alteration, loss of dexterity,
Post-hypothermic hallucinations.
Afro-American, female, age >60 yr,
Health status, anthropometry, fatigue,
Hypoxia, rain, wind, wet clothing,
Fitness level.
Weather forecasting,
Cold-weather clothing protects,
Reduce the duration of practice,
Offer warm facilities for warm-up or recovery routines.
Acute mountain sickness (AMS),
High altitude pulmonary edema (HAPE) and high altitude cerebral edema (HACE).
Individual susceptibility,
Previous history of altitude illness,
Sickle cell trait,
Permanent residence at low altitude,
Altitude severity, rate of ascent, time of exposure, sleeping quality,
Level of exertion while at altitude.
Stage ascent up to 2000 m with one day of acclimatization spend for each 300-500 m above 2000 m
Increase hydration.
Snow and avalanche
Asphyxia (airway obstruction), mechanical chest compression, and rebreathing expired air conducting to hypercapnia and hypoxia.
Warmer, moister atmosphere,
Snowpack quality and density.
Check specific information bulletin.
Carry safety gears.
Exercise-induced asthma and bronchial hyper-responsiveness *
Exercise-induced asthma and bronchial hyper-responsiveness,
Cold inhaled air,
Air pollution.
In addition to heat or cold and air pollution countermeasures:
Pollen distribution forecasting,
Avoid the full pollen season (for allergic individuals).
* Weather-related complications which may appear in addition to heat or cold and air pollution conditions.

3. Integration of the Human-Environment Interaction

3.1. From Direct Weather Indices to Thermal Stress Modeling

Among the basic weather elements (i.e., air temperature, mean radiant temperature, absolute humidity and air movement), the most commonly used is air temperature. However, considering air temperature alone is not an accurate approach to evaluate the thermal stress level. In this view, various thermal indexes have been developed over time [19,28], most of them being two-parameter indices, to apprise stressful situations (see [18,197,198,199] for comprehensive reviews of these simple indices). For instance, the WBGT (ISO 7243, ISO/DIS 7933 1984 [200], originally developed by the US Navy [201]), weighted from dry-bulb temperature, natural wet-bulb temperature and black-globe temperature for outdoor condition or wet-bulb and black-globe temperatures for indoor conditions (with approximation formula being mostly preferred [202]) probably represent the most widely used and recommended index of heat stress. Similarly, Wind-Chill Temperature (ISO 11079 [203], determined from air temperature and wind speed at 10 m above ground level) is a reference to assess cold stress. These indices have been adopted in several world’s leading sports medicine organizations position stands and guidelines on heat [12], cold [22] and altitude [10] challenges for high-level and recreational athletes. Whilst these consensus statements are fully available, the key is how well sporting organizations implement these recommendations received from leading experts. Very recently, criticisms surrounded the 2014 Australian Open Tennis Championships (i.e., with some matches played at ~44 °C) since players were apparently not made fully aware of the tournament’s extreme heat policy (i.e., decision to suspend play with ambient temperatures > 40°C and WBGT > 32.5°C, yet at the referee’s discretion). Other findings arising from the Fédération Internationale de Volleyball’s heat stress surveillance system indicate that available guidelines (e.g., ACSM [12]) are too conservative to guide informed decisions regarding whether or not it is safe to let a professional beach volley tournament continue when facing elevated heat [204]. While Budds [20] concluded that the WBGT can “only provide a general guide to the likelihood of adverse effects of heat”, Brotherhood [21] demonstrated that, regardless of the environmental conditions, the internal metabolic rate is the main driver determining exercise-induced heat strain. Because available indices are neglecting significant fluxes or variables (e.g., cloud cover which influences the intensity of solar radiation, and wind speed [20]), they can never fulfill the essential requirement that for each index value there must always be a corresponding and unique thermo-physiological state (strain), regardless of the combination of the meteorological input values (stress) [7].
When exercising outdoor, thermal stress cannot be adequately represented with two-parameter indices, essentially because they lead to misrepresentations of the thermal environment. They cannot be implemented to approximate safety thresholds, be transferred to other locations. Considering the large spatial and temporal variations of microclimate conditions [205] it is, therefore, likely that alternative thermo-physiological modeling would have more merit [18,206,207]. In this view, assessment procedures combining the four basic weather variables including the short- and long-wave radiation fluxes of the atmosphere [208], with two additional behavioral variables, i.e., the metabolic rate and clothing (insulation and moisture permeability characteristics) [209], namely heat budget models (e.g., Predicted Mean Vote (PMV [197]); Predicted Heat Strain (PHS, ISO 7933 [210]; Klima-Michel-Model (KMM [211]) were developed to better define the human thermal comfort and derived thermal stress [197]. Although heat budget models are not considered as “Gold-standards”, neither by researchers nor by end-users [7], it is worth mentioning that only thermal climate models that incorporate all parameters of the human heat budget can be used universally across all climate zones, regions and seasons [212].

3.2. The Concept of Universal Thermal Climate Index (UTCI)

Thanks to a multi-disciplinary cooperation (thermo-physiology, occupational medicine, biophysics, meteorology, bio-meteorological and environmental sciences) which allowed resolving limitations with respect to occupational settings imposed by the assumed activity level and clothing behavior, the UTCI [213] has been introduced. It corresponds to an equivalent temperature defined as a reference condition for subsequent comparison with all climatic conditions. The published literature on its development include a clothing model [214,215], a multi-node physiological model [216] (for better fitting under all metabolic rates, including very high activity levels), a single-sector thermo-physiology, consisting of a sweating heated cylinder “Torso” [217], followed by a validation and time efficient operational procedure, a regression approach based computerization [218], and assessment in real setting [219]. In particular, the UTCI meets the following requirements: (i) Thermo-physiologically responsive to all modes of heat exchange between the body and its environment; (ii) Applicable for whole-body but also for local skin cooling (frostbite) (see [220]); (iii) Valid in all climates, seasons, and time and spatial scales; and (iv) Effective for a wide range of exercise intensities [214].
As a result, the operational UTCI procedure, classified into ten categories of thermal stress ranging from “extreme cold stress” to “extreme heat stress” [221], appears useful and promising to assess the outdoor sport participants’ physiological responses to humidity and radiative loads in hot environments, as well as to wind in the cold. UTCI procedure is in good agreement with the assessment of other standards (heat budget, two-node and multi-node thermo-physiological models) concerned with the thermal environment [222]. Bearing in mind that objectives and underlying assumptions may differ when comparing ergonomics standards, the utility of the UTCI procedure for cold exposure quantification remains to be confirmed [220]. To date, local cooling of exposed skin including frostbite risk (wind chill effects), should be best regarded as a transient, rather than a steady-state phenomenon [223,224,225]. It is, therefore, anticipated that the UTCI will significantly enhance application to human health and well-being in the field of public weather services, with also promising issues in outdoor sports practice. However, the expansion of the UTCI approach still requires considerable future research effort via systematic simulations using varying metabolic rate, clothing characteristics and exposure time to different thermal stress.

4. Future Perspectives and Conclusions

Over the last 150 years, thermal physiologists and bio-meteorologists have attempted to propose an index that would accurately define thermal stress across a range of environmental situations. Meanwhile, global warming, as well as the large spatial and temporal variation of microclimatic conditions [205] exert serious challenges for outdoor sports participants. While national public weather services programs recently integrate specific information to improve individual understanding of relevant environmental issue, this also complicates the definition of appropriate sport-specific guidelines to best protect practitioners’ health.
Despite the obvious observation that a model can only be as accurate as its inputs, additional environmental parameters (e.g., sunlight, precipitation, air quality, UVR) that are known to significantly impact thermal stress levels, would need to be included when developing future models. With recent technological developments, measurement and inclusion of several environmental-related factors (i.e., air pollutants, pollens) that were not possible even few years ago, we could improve the well-being of practitioners [226]. As an example, the Air Quality Index and Global Solar UV Index [227] are relatively simple measures to indicate potential airways and skin damages. Along with other weather forecast data, integration of these indexes may serve as a vehicle to raise public awareness about the necessity to adopt appropriate protective measures. While research efforts are being addressed to assess thermal comfort during different sport activities to improve the UTCI modeling, further investigation combining UTCI with Air Quality Index and Global Solar UV Index are warranted to better consider an overall environmental stress.
As mentioned earlier in the “environmental-related risk factors” section, tolerance to thermal extremes not only depends on morphological and physiological characteristics (i.e., age, fitness, gender, acclimatization, morphology, and fat thickness being the most influencing factors) but also on psychological attributes since perception of exercise difficulty (mental awareness, perceptual strain) in challenging conditions is also highly individual. Overall, increasing thermal stress decreases self-motivation of sport practitioners [17], while subjective responses and fatigue patterns are affected by the surrounding microclimate [21,228]. Available human comfort models generally do not consider individual variations [229], while the environmentally-related perceptual research is still in its infancy [18].
To conclude, this review paper first offers an integrated view of the main environmentally-related risk factors and highlights the growing influence that they have on outdoor sports as a result of global warming (Table 1). We have also re-introduced the basis of the bio-meteorological approach and its merits for improving outdoor sport practice. Gaining knowledge about thermal physiology is imperative to improve our understanding of thermoregulatory mechanisms behind safer and more efficient outdoor sport participation. However, sport scientists and exercise physiologists are usually not well-acquainted with human comfort models and bio-meteorological knowledge. While this participates to limit potential transfers to outdoor sport applications, many omitted factors (e.g., precipitation, cloud cover) also question the ecological validity of laboratory-based studies. Incorporating perceptual responses and newly available meteorological variables (e.g., atmospheric pressure, precipitation and cloud cover, air quality, UVR), affecting substantially outdoor thermal stress, would considerably improve outdoor sport-specific modeling. Finally, integration of the interdisciplinary field of human bio-meteorology within the areas of sport sciences and exercise physiology is opening doors for promising research opportunities to improve the relevance of the available outdoor recreational and competitive sport guidelines.

Author Contributions

Franck Brocherie, Olivier Girard and Grégoire P. Millet conceived and designed the review; Franck Brocherie drafted the manuscript; Olivier Girard and Grégoire P. Millet revised it critically for important intellectual content; all authors approved the final manuscript for publication.

Conflicts of Interest

The authors declare no conflict of interest.


  1. Warburton, D.E.; Nicol, C.W.; Bredin, S.S. Health benefits of physical activity: The evidence. CMAJ 2006, 174, 801–809. [Google Scholar] [CrossRef] [PubMed]
  2. World Health Organization. Health and Development through Physical Activity and Sport; World Health Organization: Geneva, Sweden, 2003. [Google Scholar]
  3. Antunes, H.K.; Stella, S.G.; Santos, R.F.; Bueno, O.F.; de Mello, M.T. Depression, anxiety and quality of life scores in seniors after an endurance exercise program. Rev. Bras. Psiquiatr. 2005, 27, 266–271. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  4. Nabkasorn, C.; Miyai, N.; Sootmongkol, A.; Junprasert, S.; Yamamoto, H.; Arita, M.; Miyashita, K. Effects of physical exercise on depression, neuroendocrine stress hormones and physiological fitness in adolescent females with depressive symptoms. Eur. J. Public Health 2006, 16, 179–184. [Google Scholar] [CrossRef] [PubMed]
  5. Department of Health. At least five a week: Evidence on the Impact of Physical Activity and Its Relationship to Health; Department of Health, Physical Activity, Health Improvement and Prevention; Department of Health: London, UK, 2003.
  6. Keim, S.M.; Guisto, J.A.; Sullivan, J.B., Jr. Environmental thermal stress. Ann. Agric. Environ. Med. 2002, 9, 1–15. [Google Scholar] [PubMed]
  7. Jendritzky, G.; de Dear, R.; Havenith, G. UTCI—Why another thermal index? Int. J. Biometeorol. 2012, 56, 421–428. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  8. Havenith, G. Temperature regulation, heat balance and climatic stress. In Extreme Weather Events and Public Health Responses; Kirch, W., Menne, B., Bertollini, R., Eds.; Springer: Heidelberg, Gemany, 2005; pp. 69–80. [Google Scholar]
  9. Havenith, G. Individualized model of human thermoregulation for the simulation of heat stress response. J. Appl. Physiol. 2001, 90, 1943–1954. [Google Scholar] [PubMed]
  10. Bergeron, M.F.; Bahr, R.; Bartsch, P.; Bourdon, L.; Calbet, J.A.; Carlsen, K.H.; Castagna, O.; Gonzalez-Alonso, J.; Lundby, C.; Maughan, R.J.; et al. International olympic committee consensus statement on thermoregulatory and altitude challenges for high-level athletes. Br. J. Sports Med. 2012, 46, 770–779. [Google Scholar] [CrossRef] [PubMed]
  11. Sawka, M.N.; Young, A.J. Physiological systems and their responses to conditions of heat and cold. In American College of Sports Medicine's Advanced Exercise Physiology; Tipton, C.M., Ed.; Lippincott Williams and Wilkins: Philadelphia, PA, USA, 2006; pp. 535–563. [Google Scholar]
  12. Armstrong, L.E.; Casa, D.J.; Millard-Stafford, M.; Moran, D.S.; Pyne, S.W.; Roberts, W.O. American college of sports medicine position stand. Exertional heat illness during training and competition. Med. Sci. Sports Exerc. 2007, 39, 556–572. [Google Scholar] [CrossRef] [PubMed]
  13. Mountjoy, M.; Alonso, J.M.; Bergeron, M.F.; Dvorak, J.; Miller, S.; Migliorini, S.; Singh, D.G. Hyperthermic-related challenges in aquatics, athletics, football, tennis and triathlon. Br. J. Sports Med. 2012, 46, 800–804. [Google Scholar] [CrossRef] [PubMed]
  14. Bartsch, P.; Swenson, E.R. Acute high-altitude illnesses. N. Engl. J. Med. 2013, 369, 1666–1667. [Google Scholar] [CrossRef] [PubMed]
  15. Brown, R.D.; Gillespie, T.J. Estimating outdoor thermal comfort using a cylindrical radiation thermometer and an energy budget model. Int. J. Biometeorol. 1986, 30, 43–52. [Google Scholar] [CrossRef] [PubMed]
  16. Ramsey, J.D.; Chai, C.P. Inherent variability in heat-stress decision rules. Ergonomics 1983, 26, 495–504. [Google Scholar] [CrossRef] [PubMed]
  17. Kenny, N.A.; Warland, J.S.; Brown, R.D.; Gillespie, T.G. Part A: Assessing the performance of the comfa outdoor thermal comfort model on subjects performing physical activity. Int. J. Biometeorol. 2009, 53, 415–428. [Google Scholar] [CrossRef] [PubMed]
  18. Parsons, K.C. Human Thermal Environments: The Effects of Hot, Moderate and Cold Environments on Human Health, Comfort and Performance, 2nd ed.; Taylor and Francis: New York, NY, USA, 2003. [Google Scholar]
  19. Epstein, Y.; Moran, D.S. Thermal comfort and the heat stress indices. Ind. Health 2006, 44, 388–398. [Google Scholar] [CrossRef] [PubMed]
  20. Budd, G.M. Wet-bulb globe temperature (WBGT)—Its history and its limitations. J. Sci. Med. Sport 2008, 11, 20–32. [Google Scholar] [CrossRef] [PubMed]
  21. Brotherhood, J.R. Heat stress and strain in exercise and sport. J. Sci. Med. Sport 2008, 11, 6–19. [Google Scholar] [CrossRef] [PubMed]
  22. Castellani, J.W.; Young, A.J.; Ducharme, M.B.; Giesbrecht, G.G.; Glickman, E.; Sallis, R.E. American college of sports medicine position stand: Prevention of cold injuries during exercise. Med. Sci. Sports Exerc. 2006, 38, 2012–2029. [Google Scholar] [PubMed]
  23. Bos, I.; de Boever, P.; Int Panis, L.; Meeusen, R. Physical activity, air pollution and the brain. Sports Med. 2014, 44, 1505–1518. [Google Scholar] [CrossRef] [PubMed]
  24. Helenius, I.; Lumme, A.; Haahtela, T. Asthma, airway inflammation and treatment in elite athletes. Sports Med. 2005, 35, 565–574. [Google Scholar] [CrossRef] [PubMed]
  25. Jinna, S.; Adams, B.B. Ultraviolet radiation and the athlete: Risk, sun safety, and barriers to implementation of protective strategies. Sports Med. 2013, 43, 531–537. [Google Scholar] [CrossRef] [PubMed]
  26. Shibasaki, M.; Wilson, T.E.; Crandall, C.G. Neural control and mechanisms of eccrine sweating during heat stress and exercise. J. Appl. Physiol. (1985) 2006, 100, 1692–1701. [Google Scholar] [CrossRef] [PubMed]
  27. Havenith, G.; Holmr, I.; Parsons, K.C. Personal factors in thermal comfort assessment: Clothing properties and metabolic heat production. Energy Build. 2002, 34, 581–591. [Google Scholar] [CrossRef]
  28. Blazejczyk, K.; Epstein, Y.; Jendritzky, G.; Staiger, H.; Tinz, B. Comparison of UTCI to selected thermal indices. Int. J. Biometeorol. 2012, 56, 515–535. [Google Scholar] [CrossRef] [PubMed]
  29. Kampmann, B.; Brode, P.; Fiala, D. Physiological responses to temperature and humidity compared to the assessment by UTCI, WGBT and PHS. Int. J. Biometeorol. 2012, 56, 505–513. [Google Scholar] [CrossRef] [PubMed]
  30. D’Ippoliti, D.; Michelozzi, P.; Marino, C.; de’Donato, F.; Menne, B.; Katsouyanni, K.; Kirchmayer, U.; Analitis, A.; Medina-Ramon, M.; Paldy, A.; et al. The impact of heat waves on mortality in 9 European cities: Results from the EuroHeat project. Environ. Health 2010, 9. [Google Scholar] [CrossRef] [PubMed]
  31. Zacharias, S.; Koppe, C.; Mücke, H.G. Influence of heat waves on ischemic heart diseases in Germany. Climate 2014, 2, 133–152. [Google Scholar] [CrossRef]
  32. Gasparrini, A.; Armstrong, B. The impact of heat waves on mortality. Epidemiology 2011, 22, 68–73. [Google Scholar] [CrossRef] [PubMed]
  33. Roberts, W.O. Exertional heat stroke during a cool weather marathon: A case study. Med. Sci. Sports Exerc. 2006, 38, 1197–1203. [Google Scholar] [CrossRef] [PubMed]
  34. Roberts, W.O. Exercise-associated collapse in endurance events: A classification system. Physician Sportsmed. 1989, 17, 49–59. [Google Scholar]
  35. Epstein, Y.; Sohar, E.; Shapiro, Y. Exertional heatstroke: A preventable condition. Isr. J. Med. Sci. 1995, 31, 454–462. [Google Scholar] [PubMed]
  36. Keren, G.; Epstein, Y.; Magazanik, A. Temporary heat intolerance in a heatstroke patient. Aviat. Space Environ. Med. 1981, 52, 116–117. [Google Scholar] [PubMed]
  37. Sohar, E.; Michaeli, D.; Waks, U.; Shibolet, S. Heatstroke caused by dehydration and physical effort. Arch. Intern. Med. 1968, 122, 159–161. [Google Scholar] [CrossRef] [PubMed]
  38. Bouchama, A.; Knochel, J.P. Heat stroke. N. Engl. J. Med. 2002, 346, 1978–1988. [Google Scholar] [CrossRef] [PubMed]
  39. Leithead, C.S.; Lind, A.R. Heat cramps. In Heat Stress and Heat Disorders; Davis Co.: Philadelphia, PA, USA, 1964; pp. 170–177. [Google Scholar]
  40. Roberts, W.O. A 12-yr profile of medical injury and illness for the twin cities marathon. Med. Sci. Sports Exerc. 2000, 32, 1549–1555. [Google Scholar] [CrossRef] [PubMed]
  41. Bergeron, M.F. Heat cramps during tennis: A case report. Int. J. Sport Nutr. 1996, 6, 62–68. [Google Scholar] [PubMed]
  42. Bergeron, M.F. Heat cramps: Fluid and electrolyte challenges during tennis in the heat. J. Sci. Med. Sport 2003, 6, 19–27. [Google Scholar] [CrossRef]
  43. Knochel, J.P. Environmental heat illness. An eclectic review. Arch. Intern. Med. 1974, 133, 841–864. [Google Scholar] [CrossRef] [PubMed]
  44. Hubbard, R.W.; Armstrong, L.E. The heat illness: Biochemical, ultrastructural, and fluid-electrolyte considerations. In Human Performance Physiology and Environment Medicine at Terrestrial Extremes; Pandolf, K.B., Sawka, M.N., Gonzalez, R.R., Eds.; Benchmark Press: Indianapolis, IN, USA, 1988; pp. 305–359. [Google Scholar]
  45. Knochel, J.P.; Reed, G. Disorders of heat regulation. In Clinical Disorders, Fluid and Electrolyte Metabolism; Kleeman, M.H., Maxwell, C.R., Narin, R.G., Eds.; McGraw-Hill: New York, NY, USA, 1987; pp. 1197–1232. [Google Scholar]
  46. Shibolet, S.; Lancaster, M.C.; Danon, Y. Heatstroke: A review. Aviat. Space Environ. Med. 1976, 47, 280–301. [Google Scholar] [PubMed]
  47. Elias, S.R.; Roberts, W.O.; Thorson, D.C. Team sports in hot weather: Guidelines for modifying youth soccer. Physician Sportsmed. 1991, 19, 67–68. [Google Scholar]
  48. Aarseth, H.P.; Eide, I.; Skeie, B.; Thaulow, E. Heatstroke in endurance exercise. Acta Med. Scand. 1986, 220, 279–283. [Google Scholar] [CrossRef] [PubMed]
  49. Graber, C.D.; Reinhold, R.B.; Breman, J.G. Fatal heatstroke. JAMA 1971, 216, 1195–1196. [Google Scholar] [CrossRef] [PubMed]
  50. Hanson, P.G.; Zimmerman, S.W. Exertional heatstroke in novice runners. JAMA 1979, 242, 154–158. [Google Scholar] [CrossRef] [PubMed]
  51. Sutton, J.R.; Bar-Or, O. Thermal illness in fun running. Am. Heart J. 1980, 100, 778–781. [Google Scholar] [CrossRef]
  52. Armstrong, L.E.; Maresh, C.M.; Crago, A.E.; Adams, R.; Roberts, W.O. Interpretation of aural temperatures during exercise, hypothermia, and cooling therapy. Med. Exerc. Nutr. Health 1994, 3, 9–16. [Google Scholar]
  53. Sutton, J.R.; Coleman, M.J.; Millar, A.P.; Lazarus, L.; Russo, P. The medical problems of mass participation in athletic competition. The “City-to-Surf” race. Med. J. Aust. 1972, 2, 127–133. [Google Scholar] [PubMed]
  54. Armstrong, L.E.; de Luca, J.P.; Hubbard, R.W. Time course of recovery and heat acclimation ability of prior exertional heatstroke patients. Med. Sci. Sports Exerc. 1990, 22, 36–48. [Google Scholar] [CrossRef] [PubMed]
  55. Epstein, Y. Heat intolerance: Predisposing factor or residual injury? Med. Sci. Sports Exerc. 1990, 22, 29–35. [Google Scholar] [CrossRef] [PubMed]
  56. Carter, R.; Cheuvront, S.N.; Williams, J.O.; Kolka, M.A.; Stephenson, L.A.; Sawka, M.N.; Amoroso, P.J. Epidemiology of hospitalizations and deaths from heat illness in soldiers. Med. Sci. Sports Exerc. 2005, 37, 1338–1344. [Google Scholar] [CrossRef] [PubMed]
  57. Kerle, K.K.; Nishimura, K.D. Exertional collapse and sudden death associated with sickle cell trait. Am. Fam. Physician 1996, 54, 237–240. [Google Scholar] [PubMed]
  58. Holtzhausen, L.M.; Noakes, T.D. Collapsed ultradistance athlete: Proposed mechanisms and an approach to management. Clin. J. Sport Med. 1997, 7, 292–301. [Google Scholar] [CrossRef] [PubMed]
  59. Midgley, A.W.; McNaughton, L.R.; Wilkinson, M. Is there an optimal training intensity for enhancing the maximal oxygen uptake of distance runners?: Empirical research findings, current opinions, physiological rationale and practical recommendations. Sports Med. 2006, 36, 117–132. [Google Scholar] [CrossRef] [PubMed]
  60. Ross, M.; Abbiss, C.; Laursen, P.; Martin, D.; Burke, L. Precooling methods and their effects on athletic performance: A systematic review and practical applications. Sports Med. 2013, 43, 207–225. [Google Scholar] [CrossRef] [PubMed]
  61. Lorenzo, S.; Halliwill, J.R.; Sawka, M.N.; Minson, C.T. Heat acclimation improves exercise performance. J. Appl. Physiol. 2010, 109, 1140–1147. [Google Scholar] [CrossRef] [PubMed]
  62. Sawka, M.N.; Leon, L.R.; Montain, S.J.; Sonna, L.A. Integrated physiological mechanisms of exercise performance, adaptation, and maladaptation to heat stress. Compr. Physiol. 2011, 1, 1883–1928. [Google Scholar] [PubMed]
  63. Pandolf, K.B.; Burse, R.L.; Goldman, R.F. Role of physical fitness in heat acclimatization, decay and reinduction. Ergonomics 1977, 20, 399–408. [Google Scholar] [CrossRef] [PubMed]
  64. Shvartz, E.; Shapiro, Y.; Magazanik, A.; Meroz, A.; Birnfeld, H.; Mechtinger, A.; Shibolet, S. Heat acclimation, physical fitness, and responses to exercise in temperate and hot environments. J. Appl. Physiol. Respir. Environ. Exerc. Physiol. 1977, 43, 678–683. [Google Scholar] [PubMed]
  65. Armstrong, L.E.; Maresh, C.M. The induction and decay of heat acclimatisation in trained athletes. Sports Med. 1991, 12, 302–312. [Google Scholar] [CrossRef] [PubMed]
  66. Cotter, J.D.; Thornton, S.N.; Lee, J.K.; Laursen, P.B. Are we being drowned in hydration advice? Thirsty for more? Extrem. Physiol. Med. 2014, 3. [Google Scholar] [CrossRef] [PubMed]
  67. Adams, B.B. Sports Dermatology; Springer: Berlin, Germany, 2006. [Google Scholar]
  68. Bikle, D.D. The vitamin D receptor: A tumor suppressor in skin. Adv. Exp. Med. Biol. 2014, 810, 282–302. [Google Scholar] [CrossRef] [PubMed]
  69. Thompson, J.F.; Scolyer, R.A.; Kefford, R.F. Cutaneous melanoma. Lancet 2005, 365, 687–701. [Google Scholar] [CrossRef]
  70. Moehrle, M. Outdoor sports and skin cancer. Clin. Dermatol. 2008, 26, 12–15. [Google Scholar] [CrossRef] [PubMed]
  71. Miller, A.J.; Mihm, M.C., Jr. Melanoma. N. Engl. J. Med. 2006, 355, 51–65. [Google Scholar] [CrossRef] [PubMed]
  72. Curado, M.P.; Edwards, B.; Shin, H.R.; Storm, H.; Heanue, M.; Boyle, P.; Ferlay, J. Cancer Incidence in Five Continents; International Agency for Research on Cancer (IARC) Scientific Publication: Lyon, France, 2007. [Google Scholar]
  73. Ferlay, J.; Soerjomataram, I.; Ervik, M.; Dikshit, R.; Eser, S.; Mathers, C.; Rebelo, M.; Parkin, D.M.; Forman, D.; Bray, F. Cancer Incidence and Mortality Worldwide. Available online: (accessed on 2 July 2015).
  74. Williams, M.L.; Pennella, R. Melanoma, melanocytic nevi, and other melanoma risk factors in children. J. Pediatr. 1994, 124, 833–845. [Google Scholar] [CrossRef]
  75. Moehrle, M.; Koehle, W.; Dietz, K.; Lischka, G. Reduction of minimal erythema dose by sweating. Photodermatol. Photoimmunol. Photomed. 2000, 16, 260–262. [Google Scholar] [CrossRef] [PubMed]
  76. Blumthaler, M. Solar UV measurements. In UV-B radiation and ozone depletion. Effects on Humans, Animals, Plants, Microorganisms, and Materials; Tevini, M., Ed.; Lewis: Boca Raton, FL, USA, 1993; pp. 71–94. [Google Scholar]
  77. Moehrle, M.; Dennenmoser, B.; Garbe, C. Continuous long-term monitoring of UV radiation in professional mountain guides reveals extremely high exposure. Int. J. Cancer 2003, 103, 775–778. [Google Scholar] [CrossRef] [PubMed]
  78. Chadysiene, R.; Girgzdys, A. Ultraviolet radiation albedo of natural surfaces. J. Environ. Eng. Landsc. Manag. 2008, 16, 83–88. [Google Scholar] [CrossRef]
  79. Han, A.; Maibach, H.I. Management of acute sunburn. Am. J. Clin. Dermatol. 2004, 5, 39–47. [Google Scholar] [CrossRef] [PubMed]
  80. Berndt, N.C.; O’Riordan, D.L.; Winkler, E.; McDermott, L.; Spathonis, K.; Owen, N. Social cognitive correlates of young adult sport competitors’ sunscreen use. Health Educ. Behav. 2011, 38, 6–14. [Google Scholar] [CrossRef] [PubMed]
  81. Moehrle, M. Ultraviolet exposure in the ironman triathlon. Med. Sci. Sports Exerc. 2001, 33, 1385–1386. [Google Scholar] [CrossRef] [PubMed]
  82. Lawler, S.; Spathonis, K.; Eakin, E.; Gallois, C.; Leslie, E.; Owen, N. Sun exposure and sun protection behaviours among young adult sport competitors. Aust. N. Z. J. Public Health 2007, 31, 230–234. [Google Scholar] [CrossRef] [PubMed]
  83. Parrott, R.; Duggan, A.; Cremo, J.; Eckles, A.; Jones, K.; Steiner, C. Communicating about youth’s sun exposure risk to soccer coaches and parents: A pilot study in Georgia. Health Educ. Behav. 1999, 26, 385–395. [Google Scholar] [CrossRef] [PubMed]
  84. Glanz, K.; Geller, A.C.; Shigaki, D.; Maddock, J.E.; Isnec, M.R. A randomized trial of skin cancer prevention in aquatics settings: The pool cool program. Health Psychol. 2002, 21, 579–587. [Google Scholar] [CrossRef] [PubMed]
  85. Walkosz, B.; Voeks, J.; Andersen, P.; Scott, M.; Buller, D.; Cutter, G.; Dignan, M. Randomized trial on sun safety education at ski and snowboard schools in Western North America. Pediatr. Dermatol. 2007, 24, 222–229. [Google Scholar] [CrossRef] [PubMed]
  86. Geller, A.C.; Glanz, K.; Shigaki, D.; Isnec, M.R.; Sun, T.; Maddock, J. Impact of skin cancer prevention on outdoor aquatics staff: The pool cool program in Hawaii and Massachusetts. Prev. Med. 2001, 33, 155–161. [Google Scholar] [CrossRef] [PubMed]
  87. Cooper, M.A.; Marshburn, S. Lightning strike and electric shock survivors, international. NeuroRehabilitation 2005, 20, 43–47. [Google Scholar] [PubMed]
  88. Pfaff, J. Lightning injuries. In Emergency Medicine; Marx, J., Hocknerger, R., Walls, R., Eds.; WB Saunders: Philiadelphia, PA, USA, 1998; p. 1560. [Google Scholar]
  89. Lopez, R.E.; Holle, R.L. Diurnal and spatial variability of lightning activity in northeastern Colorado and central Florida during the summer. Mon. Weather Rev. 1986, 114, 1288–1312. [Google Scholar] [CrossRef]
  90. Watson, A.I.; Lopez, R.E.; Holle, R.L. Diurnal cloud-to-ground lightning patterns in Arizona during the southwest monsoon. Mon. Weather Rev. 1994, 122, 1716–1725. [Google Scholar] [CrossRef]
  91. DeFranco, M.J.; Baker, C.L., 3rd; DaSilva, J.J.; Piasecki, D.P.; Bach, B.R., Jr. Environmental issues for team physicians. Am. J. Sports Med. 2008, 36, 2226–2237. [Google Scholar] [CrossRef] [PubMed]
  92. Fish, R. Lightning injuries. In Emergency Medicine: A Comprehensive Study Guide; Tintinalli, J., Kelen, G., Stapczynski, J., Ma, O., Cline, D., Eds.; McGraw-Hill: New York, NY, USA, 2004; pp. 1235–1238. [Google Scholar]
  93. Cooper, M.A. Lightning injuries: Prognostic signs for death. Ann. Emerg. Med. 1980, 9, 134–138. [Google Scholar] [CrossRef]
  94. Muehlberger, T.; Vogt, P.M.; Munster, A.M. The long-term consequences of lightning injuries. Burns 2001, 27, 829–833. [Google Scholar] [CrossRef]
  95. Hendler, N. Overlooked diagnoses in chronic pain: Analysis of survivors of electric shock and lightning strike. J. Occup. Environ. Med. 2005, 47, 796–805. [Google Scholar] [PubMed]
  96. Maghsoudi, H.; Adyani, Y.; Ahmadian, N. Electrical and lightning injuries. J. Burn Care Res. 2007, 28, 255–261. [Google Scholar] [CrossRef] [PubMed]
  97. Walsh, K.M. Lightning and severe thunderstorms in event management. Curr. Sports Med. Rep. 2012, 11, 131–134. [Google Scholar] [CrossRef] [PubMed]
  98. Cooper, M.A.; Andrews, C.J.; Holle, R.L. Lightning injuries. In Wilderness Medicine, 5th ed.; Auerbach, P.S., Ed.; Mosby: St Louis, MO, USA, 2007; pp. 67–108. [Google Scholar]
  99. Brasseur, G. Implications of climate change for air quality. WMO Bull. 2009, 58, 10–15. [Google Scholar]
  100. Kaur, S.; Nieuwenhuijsen, M.J.; Colvilea, R.N. Pedestrian exposure to air pollution along a major road in central London, UK. Atmos. Environ. 2005, 39, 7307–7320. [Google Scholar] [CrossRef]
  101. World Health Organization. Environmental Health Criteria 213: Carbon Monoxide; World Health Organization (WHO): Geneva, Sweden, 1999. [Google Scholar]
  102. United States Environmental Protection Agency. Air Quality Criteria for Ozone and Related Photochemical Oxidants; United States Environmental Protection Agency (EPA): Chicago, IL, USA, 2005.
  103. Strak, M.; Boogaard, H.; Meliefste, K.; Oldenwening, M.; Zuurbier, M.; Brunekreef, B.; Hoek, G. Respiratory health effects of ultrafine and fine particle exposure in cyclists. Occup. Environ. Med. 2010, 67, 118–124. [Google Scholar] [CrossRef] [PubMed]
  104. McCreanor, J.; Cullinan, P.; Nieuwenhuijsen, M.J.; Stewart-Evans, J.; Malliarou, E.; Jarup, L.; Harrington, R.; Svartengren, M.; Han, I.K.; Ohman-Strickland, P.; et al. Respiratory effects of exposure to diesel traffic in persons with asthma. N. Engl. J. Med. 2007, 357, 2348–2358. [Google Scholar] [CrossRef] [PubMed]
  105. Chimenti, L.; Morici, G.; Paterno, A.; Bonanno, A.; Vultaggio, M.; Bellia, V.; Bonsignore, M.R. Environmental conditions, air pollutants, and airway cells in runners: A longitudinal field study. J. Sports Sci. 2009, 27, 925–935. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  106. Cohen, A.J. Air pollution and lung cancer: What more do we need to know? Thorax 2003, 58, 1010–1012. [Google Scholar] [CrossRef] [PubMed]
  107. Lisabeth, L.D.; Escobar, J.D.; Dvonch, J.T.; Sanchez, B.N.; Majersik, J.J.; Brown, D.L.; Smith, M.A.; Morgenstern, L.B. Ambient air pollution and risk for ischemic stroke and transient ischemic attack. Ann. Neurol. 2008, 64, 53–59. [Google Scholar] [CrossRef] [PubMed]
  108. McConnell, R.; Berhane, K.; Gilliland, F.; London, S.J.; Islam, T.; Gauderman, W.J.; Avol, E.; Margolis, H.G.; Peters, J.M. Asthma in exercising children exposed to ozone: A cohort study. Lancet 2002, 359, 386–391. [Google Scholar] [CrossRef]
  109. Pope, C.A., 3rd; Muhlestein, J.B.; May, H.T.; Renlund, D.G.; Anderson, J.L.; Horne, B.D. Ischemic heart disease events triggered by short-term exposure to fine particulate air pollution. Circulation 2006, 114, 2443–2448. [Google Scholar] [CrossRef] [PubMed]
  110. Suwa, T.; Hogg, J.C.; Quinlan, K.B.; Ohgami, A.; Vincent, R.; van Eeden, S.F. Particulate air pollution induces progression of atherosclerosis. J. Am. Coll. Cardiol. 2002, 39, 935–942. [Google Scholar] [CrossRef]
  111. Ostro, B. Outdoor air pollution: Assessing the environmental burden of disease at national and local levels. In Environmental Burden of Disease Series, No. 5; World Health Organization: Geneva, Sweden, 2004. [Google Scholar]
  112. Niinimaa, V.; Cole, P.; Mintz, S.; Shephard, R.J. The switching point from nasal to oronasal breathing. Respir. Physiol. 1980, 42, 61–71. [Google Scholar] [CrossRef]
  113. Daigle, C.C.; Chalupa, D.C.; Gibb, F.R.; Morrow, P.E.; Oberdorster, G.; Utell, M.J.; Frampton, M.W. Ultrafine particle deposition in humans during rest and exercise. Inhal. Toxicol. 2003, 15, 539–552. [Google Scholar] [CrossRef] [PubMed]
  114. Londahl, J.; Massling, A.; Pagels, J.; Swietlicki, E.; Vaclavik, E.; Loft, S. Size-resolved respiratory-tract deposition of fine and ultrafine hydrophobic and hygroscopic aerosol particles during rest and exercise. Inhal. Toxicol. 2007, 19, 109–116. [Google Scholar] [CrossRef] [PubMed]
  115. Giles, L.V.; Koehle, M.S. The health effects of exercising in air pollution. Sports Med. 2014, 44, 223–249. [Google Scholar] [CrossRef] [PubMed]
  116. Martinez-Campos, C.; Lara-Padilla, E.; Bobadilla-Lugo, R.A.; Kross, R.D.; Villanueva, C. Effects of exercise on oxidative stress in rats induced by ozone. Sci. World J. 2012, 2012. [Google Scholar] [CrossRef] [PubMed]
  117. Vieira, R.P.; Toledo, A.C.; Silva, L.B.; Almeida, F.M.; Damaceno-Rodrigues, N.R.; Caldini, E.G.; Santos, A.B.; Rivero, D.H.; Hizume, D.C.; Lopes, F.D.; et al. Anti-inflammatory effects of aerobic exercise in mice exposed to air pollution. Med. Sci. Sports Exerc. 2012, 44, 1227–1234. [Google Scholar] [PubMed]
  118. Yu, Y.B.; Liao, Y.W.; Su, K.H.; Chang, T.M.; Shyue, S.K.; Kou, Y.R.; Lee, T.S. Prior exercise training alleviates the lung inflammation induced by subsequent exposure to environmental cigarette smoke. Acta Physiol. (Oxf.) 2012, 205, 532–540. [Google Scholar] [CrossRef] [PubMed]
  119. De Hartog, J.; Boogaart, H.; Nijland, H.; Hoek, G. Do the health benefits of cycling outweigh the risks? Environ. Health Perspect. 2010, 118, 1109–1116. [Google Scholar] [CrossRef] [PubMed]
  120. Hamer, M.; Chida, Y. Active commuting and cardiovascular risk: A meta-analytic review. Prev. Med. 2008, 46, 9–13. [Google Scholar] [CrossRef] [PubMed]
  121. Wong, C.M.; Ou, C.Q.; Thach, T.Q.; Chau, Y.K.; Chan, K.P.; Ho, S.Y.; Chung, R.Y.; Lam, T.H.; Hedley, A.J. Does regular exercise protect against air pollution-associated mortality? Prev. Med. 2007, 44, 386–392. [Google Scholar] [CrossRef] [PubMed]
  122. Dong, G.H.; Zhang, P.; Sun, B.; Zhang, L.; Chen, X.; Ma, N.; Yu, F.; Guo, H.; Huang, H.; Lee, Y.L.; et al. Long-term exposure to ambient air pollution and respiratory disease mortality in Shenyang, China: A 12-year population-based retrospective cohort study. Respiration 2012, 84, 360–368. [Google Scholar] [CrossRef] [PubMed]
  123. Lloyd, E.L. ABC of sports medicine. Temperature and performance. I: Cold. BMJ 1994, 309, 531–534. [Google Scholar] [CrossRef] [PubMed]
  124. Eurowinter Group. Cold exposure and winter mortality from ischaemic heart disease, cerebrovascular disease, respiratory disease, and all causes in warm and cold regions of Europe. Lancet 1997, 349, 1341–1346. [Google Scholar]
  125. Keatinge, W. Medical problems of cold weather. The oliver-sharpey lecture 1985. J. R. Coll. Physicians Lond. 1986, 20, 283–287. [Google Scholar] [PubMed]
  126. Gagge, A.P.; Gonzalez, R.R. Mechanisms of heat exchange: Biophysics and physiology. In Handbook of Physiology: Environmental Physiology; Fregly, M.J., Blatteis, C.M., Eds.; Amercian Physiology Society: Bethesda, MD, USA, 1996; pp. 45–84. [Google Scholar]
  127. Gonzalez, R.R.; Sawka, M.N. Biophysics of heat transfer and clothing considerations. In Human Performance Physiology and Environmental Medicine at Terrestrial Extremes; Pandolf, K.B., Sawka, M.N., Gonzalez, R.R., Eds.; Benchmark: Indianapolis, IN, USA, 1988; pp. 45–95. [Google Scholar]
  128. Cappaert, T.A.; Stone, J.A.; Castellani, J.W.; Krause, B.A.; Smith, D.; Stephens, B.A. National athletic trainers’ association position statement: Environmental cold injuries. J. Athl. Train. 2008, 43, 640–658. [Google Scholar] [CrossRef] [PubMed]
  129. Simmons, G.H.; Barrett-O’Keefe, Z.; Minson, C.T.; Halliwill, J.R. Cutaneous vascular and core temperature responses to sustained cold exposure in hypoxia. Exp. Physiol. 2011, 96, 1062–1071. [Google Scholar] [CrossRef] [PubMed]
  130. Thomas, J.R.; Oakley, E.H.N. Nonfreezing cold injury. In Textbooks of Military Medicine: Medical Aspects of Harsh Environments, Volume 1; Pandolf, K.B., Burr, R.E., Eds.; Office of the Surgeon General, U.S. Army: Falls Church, VA, USA, 2002; pp. 467–490. [Google Scholar]
  131. Hamlet, M.P. Nonfreezing cold injuries. In Textbook of Wilderness Medicine; Auerbach, P.S., Ed.; Mosby: St Louis, MO, USA, 2001; pp. 129–134. [Google Scholar]
  132. Sallis, R.; Chassay, C.M. Recognizing and treating common cold-induced injury in outdoor sports. Med. Sci. Sports Exerc. 1999, 31, 1367–1373. [Google Scholar] [CrossRef] [PubMed]
  133. Danzl, D.F. Accidental hypothermia. In Rosen’s Emergency Medicine; Marx, J.A., Ed.; Mosby: St Louis, MO, USA, 2002; pp. 1979–1996. [Google Scholar]
  134. Ulrich, A.S.; Rathlev, N.K. Hypothermia and localized cold injuries. Emerg. Med. Clin. North Am. 2004, 22, 281–298. [Google Scholar] [CrossRef] [PubMed]
  135. Murphy, J.V.; Banwell, P.E.; Roberts, A.H.; McGrouther, D.A. Frostbite: Pathogenesis and treatment. J. Trauma 2000, 48, 171–178. [Google Scholar] [CrossRef] [PubMed]
  136. Hamlet, M.P. Prevention and treatment of cold injury. Int. J. Circumpolar Health 2000, 59, 108–113. [Google Scholar] [PubMed]
  137. Hassi, J. Frostbite, a common cold injury: Challenges in treatment and prevention. Int. J. Circumpolar Health 2000, 59, 90–91. [Google Scholar] [PubMed]
  138. Castellani, J.W.; Young, A.J. Health and performance challenges during sports training and competition in cold weather. Br. J. Sports Med. 2012, 46, 788–791. [Google Scholar] [CrossRef] [PubMed]
  139. DeGroot, D.W.; Castellani, J.W.; Williams, J.O.; Amoroso, P.J. Epidemiology of U.S. Army cold weather injuries, 1980–1999. Aviat. Space Environ. Med. 2003, 74, 564–570. [Google Scholar] [PubMed]
  140. Pozos, R.S.; Danzl, D.F. Human physiological responses to cold stress and hypothermia. In Textbooks of Military Medicine: Medical Aspects of Harsh Environments, Volume 1; Pandolf, K.B., Burr, R.E., Eds.; Office of the Surgeon General, U.S. Army: Falls Church, VA, USA, 2002; pp. 351–382. [Google Scholar]
  141. Glickman-Weiss, E.L.; Nelson, A.G.; Hearon, C.M.; Prisby, R.; Caine, N. Thermal and metabolic responses of women with high fat versus low fat body composition during exposure to 5 and 27 degrees C for 120 min. Aviat. Space Environ. Med. 1999, 70, 284–288. [Google Scholar] [PubMed]
  142. Hayward, M.G.; Keatinge, W.R. Roles of subcutaneous fat and thermoregulatory reflexes in determining ability to stabilize body temperature in water. J. Physiol. 1981, 320, 229–251. [Google Scholar] [CrossRef] [PubMed]
  143. McArdle, W.D.; Magel, J.R.; Gergley, T.J.; Spina, R.J.; Toner, M.M. Thermal adjustment to cold-water exposure in resting men and women. J. Appl. Physiol. Respir. Environ. Exerc. Physiol. 1984, 56, 1565–1571. [Google Scholar] [PubMed]
  144. Sloan, R.E.; Keatinge, W.R. Cooling rates of young people swimming in cold water. J. Appl. Physiol. 1973, 35, 371–375. [Google Scholar] [PubMed]
  145. Tikuisis, P.; Jacobs, I.; Moroz, D.; Vallerand, A.L.; Martineau, L. Comparison of thermoregulatory responses between men and women immersed in cold water. J. Appl. Physiol. (1985) 2000, 89, 1403–1411. [Google Scholar]
  146. Candler, W.H.; Ivey, H. Cold weather injuries among U.S. Soldiers in Alaska: A five-year review. Mil. Med. 1997, 162, 788–791. [Google Scholar] [PubMed]
  147. Taylor, M.S. Cold weather injuries during peacetime military training. Mil. Med. 1992, 157, 602–604. [Google Scholar] [PubMed]
  148. Falk, B.; Bar-Or, O.; Smolander, J.; Frost, G. Response to rest and exercise in the cold: Effects of age and aerobic fitness. J. Appl. Physiol. (1985) 1994, 76, 72–78. [Google Scholar]
  149. Smolander, J. Effect of cold exposure on older humans. Int. J. Sports Med. 2002, 23, 86–92. [Google Scholar] [CrossRef] [PubMed]
  150. Young, A.J.; Sawka, M.N.; Pandolf, K.B. Physiology of cold exposure. In Nutritional Needs in Cold and in High-Altitude Environments; Marriot, B.M., Carlson, S.J., Eds.; National Academy Press: Washington, DC, USA, 1996; pp. 127–147. [Google Scholar]
  151. Belding, H.S. Protection against dry cold. In Physiology of Heat Regulation and the Science of Clothing; Newburgh, L.H., Ed.; Saunders, W.B.: Philadelphia, PA, USA, 1949; pp. 351–366. [Google Scholar]
  152. Froese, G.; Burton, A.C. Heat losses from the human head. J. Appl. Physiol. 1957, 10, 235–241. [Google Scholar] [PubMed]
  153. Department of the Army. Prevention and Management of Cold-Weather Injuries; Department of the Army: Washington, DC, USA, 2005; p. 508. [Google Scholar]
  154. Holton, J.R. Introduction to Dynamic Meteorology, 4th ed.; International Geophysics Series; Elsevier Academic Press: San Diego, CA, USA, 2004. [Google Scholar]
  155. Chapman, R.F.; Levine, B.D. The effects of hypo and hyperbaria on sport performance. In Exercise and Sports Science; Garrett, W.E., Kirkendall, J.T., Eds.; Lippincott, Williams & Wilkins: Philadelphia, PA, USA, 2000; pp. 447–458. [Google Scholar]
  156. Peronnet, F.; Thibault, G.; Cousineau, D.L. A theoretical analysis of the effect of altitude on running performance. J. Appl. Physiol. (1985) 1991, 70, 399–404. [Google Scholar]
  157. Mehta, R.D. Aerodynamics of sports balls. Annu. Rev. Fluid Mech. 1985, 17, 151–189. [Google Scholar] [CrossRef]
  158. Schommer, K.; Menold, E.; Subudhi, A.W.; Bartsch, P. Health risk for athletes at moderate altitude and normobaric hypoxia. Br. J. Sports Med. 2012, 46, 828–832. [Google Scholar] [CrossRef] [PubMed]
  159. Bartsch, P.; Saltin, B. General introduction to altitude adaptation and mountain sickness. Scand. J. Med. Sci. Sports 2008, 18, 1–10. [Google Scholar] [CrossRef] [PubMed]
  160. Franklin, Q.J.; Compeggie, M. Splenic syndrome in sickle cell trait: Four case presentations and a review of the literature. Mil. Med. 1999, 164, 230–233. [Google Scholar] [PubMed]
  161. Tiernan, C.J. Splenic crisis at high altitude in 2 white men with sickle cell trait. Ann. Emerg. Med. 1999, 33, 230–233. [Google Scholar] [CrossRef]
  162. Schneider, M.; Bernasch, D.; Weymann, J.; Holle, R.; Bartsch, P. Acute mountain sickness: Influence of susceptibility, preexposure, and ascent rate. Med. Sci. Sports Exerc. 2002, 34, 1886–1891. [Google Scholar] [CrossRef] [PubMed]
  163. Basnyat, B.; Murdoch, D.R. High-altitude illness. Lancet 2003, 361, 1967–1974. [Google Scholar] [CrossRef]
  164. Hackett, P.H.; Roach, R.C. High-altitude illness. N. Engl. J. Med. 2001, 345, 107–114. [Google Scholar] [CrossRef] [PubMed]
  165. Millet, G.P.; Roels, B.; Schmitt, L.; Woorons, X.; Richalet, J.P. Combining hypoxic methods for peak performance. Sports Med. 2010, 40, 1–25. [Google Scholar] [CrossRef] [PubMed]
  166. Millet, G.P.; Faiss, R.; Brocherie, F.; Girard, O. Hypoxic training and team sports: A challenge to traditional methods? Br. J. Sports Med. 2013, 47, i6–i7. [Google Scholar] [CrossRef] [PubMed]
  167. Fulco, C.S.; Beidleman, B.A.; Muza, S.R. Effectiveness of preacclimatization strategies for high-altitude exposure. Exerc. Sport Sci. Rev. 2013, 41, 55–63. [Google Scholar] [CrossRef] [PubMed]
  168. Butterfield, G.E. Nutrient requirements at high altitude. Clin. Sports Med. 1999, 18, 607–621. [Google Scholar] [CrossRef]
  169. Fukui, K.; Fujii, Y.; Ageta, Y.; Asahi, K. Changes in the lower limit of mountain permafrost between 1973 and 2004 in the Khumbu Himal, the Nepal Himalayas. Glob. Planet. Chang. 2007, 55, 251–256. [Google Scholar] [CrossRef]
  170. Morello, L. Winter Olympics: Downhill forecast. Nature 2014, 506, 21–22. [Google Scholar] [CrossRef] [PubMed]
  171. Bogle, L.B.; Boyd, J.J.; McLaughlin, K.A. Triaging multiple victims in an avalanche setting: The avalanche survival optimizing rescue triage algorithmic approach. Wilderness Environ. Med. 2010, 21, 28–34. [Google Scholar] [CrossRef] [PubMed]
  172. Procter, E.; Strapazzon, G.; Dal Cappello, T.; Castlunger, L.; Staffler, H.P.; Brugger, H. Adherence of backcountry winter recreationists to avalanche prevention and safety practices in northern Italy. Scand. J. Med. Sci. Sports 2014, 24, 823–829. [Google Scholar] [CrossRef] [PubMed]
  173. Brugger, H.; Durrer, B.; Elsensohn, F.; Paal, P.; Strapazzon, G.; Winterberger, E.; Zafren, K.; Boyd, J. Resuscitation of avalanche victims: Evidence-based guidelines of the international commission for mountain emergency medicine (icar medcom): Intended for physicians and other advanced life support personnel. Resuscitation 2013, 84, 539–546. [Google Scholar] [CrossRef] [PubMed]
  174. Kragh, J.F., Jr.; Walters, T.J.; Baer, D.G.; Fox, C.J.; Wade, C.E.; Salinas, J.; Holcomb, J.B. Survival with emergency tourniquet use to stop bleeding in major limb trauma. Ann. Surg. 2009, 249, 1–7. [Google Scholar] [CrossRef] [PubMed]
  175. Giesbrecht, G.G. Prehospital treatment of hypothermia. Wilderness Environ. Med. 2001, 12, 24–31. [Google Scholar] [CrossRef]
  176. Brugger, H.; Etter, H.J.; Zweifel, B.; Mair, P.; Hohlrieder, M.; Ellerton, J.; Elsensohn, F.; Boyd, J.; Sumann, G.; Falk, M. The impact of avalanche rescue devices on survival. Resuscitation 2007, 75, 476–483. [Google Scholar] [CrossRef] [PubMed]
  177. Haegeli, P.; Falk, M.; Procter, E.; Zweifel, B.; Jarry, F.; Logan, S.; Kronholm, K.; Biskupic, M.; Brugger, H. The effectiveness of avalanche airbags. Resuscitation 2014, 85, 1197–1203. [Google Scholar] [CrossRef] [PubMed]
  178. Tikkanen, H.; Helenius, I. Asthma in runners. BMJ 1994, 309, 1087. [Google Scholar] [CrossRef] [PubMed]
  179. World Health Organization; World Meteorological Organization. Atlas of Health and Climate; World Meteorological Organization (WMO): Geneva, 2012. [Google Scholar]
  180. Carlsen, K.H. Sports in extreme conditions: The impact of exercise in cold temperatures on asthma and bronchial hyper-responsiveness in athletes. Br. J. Sports Med. 2012, 46, 796–799. [Google Scholar] [CrossRef] [PubMed]
  181. Larsson, K.; Tornling, G.; Gavhed, D.; Muller-Suur, C.; Palmberg, L. Inhalation of cold air increases the number of inflammatory cells in the lungs in healthy subjects. Eur. Respir. J. 1998, 12, 825–830. [Google Scholar] [CrossRef] [PubMed]
  182. Larsson, K.; Ohlsen, P.; Larsson, L.; Malmberg, P.; Rydstrom, P.O.; Ulriksen, H. High prevalence of asthma in cross country skiers. BMJ 1993, 307, 1326–1329. [Google Scholar] [CrossRef] [PubMed]
  183. Fitch, K.D. An overview of asthma and airway hyper-responsiveness in Olympic athletes. Br. J. Sports Med. 2012, 46, 413–416. [Google Scholar] [CrossRef] [PubMed]
  184. Wilber, R.L.; Rundell, K.W.; Szmedra, L.; Jenkinson, D.M.; Im, J.; Drake, S.D. Incidence of exercise-induced bronchospasm in Olympic winter sport athletes. Med. Sci. Sports Exerc. 2000, 32, 732–737. [Google Scholar] [CrossRef] [PubMed]
  185. Helenius, I.J.; Rytila, P.; Metso, T.; Haahtela, T.; Venge, P.; Tikkanen, H.O. Respiratory symptoms, bronchial responsiveness, and cellular characteristics of induced sputum in elite swimmers. Allergy 1998, 53, 346–352. [Google Scholar] [CrossRef] [PubMed]
  186. Helenius, I.; Rytila, P.; Sarna, S.; Lumme, A.; Helenius, M.; Remes, V.; Haahtela, T. Effect of continuing or finishing high-level sports on airway inflammation, bronchial hyperresponsiveness, and asthma: A 5-year prospective follow-up study of 42 highly trained swimmers. J. Allergy Clin. Immunol. 2002, 109, 962–968. [Google Scholar] [CrossRef] [PubMed]
  187. Mannix, E.T.; Farber, M.O.; Palange, P.; Galassetti, P.; Manfredi, F. Exercise-induced asthma in figure skaters. Chest 1996, 109, 312–315. [Google Scholar] [CrossRef] [PubMed]
  188. Provost-Craig, M.A.; Arbour, K.S.; Sestili, D.C.; Chabalko, J.J.; Ekinci, E. The incidence of exercise-induced bronchospasm in competitive figure skaters. J. Asthma 1996, 33, 67–71. [Google Scholar] [CrossRef] [PubMed]
  189. Lumme, A.; Haahtela, T.; Ounap, J.; Rytila, P.; Obase, Y.; Helenius, M.; Remes, V.; Helenius, I. Airway inflammation, bronchial hyperresponsiveness and asthma in elite ice hockey players. Eur. Respir. J. 2003, 22, 113–117. [Google Scholar] [CrossRef] [PubMed]
  190. Helenius, I.J.; Tikkanen, H.O.; Haahtela, T. Association between type of training and risk of asthma in elite athletes. Thorax 1997, 52, 157–160. [Google Scholar] [CrossRef] [PubMed]
  191. Koh, Y.I.; Choi, I.S. Seasonal difference in the occurrence of exercise-induced bronchospasm in asthmatics: Dependence on humidity. Respiration 2002, 69, 38–45. [Google Scholar] [CrossRef] [PubMed]
  192. McFadden, E.R., Jr.; Ingram, R.H., Jr. Exercise-induced asthma: Observations on the initiating stimulus. N. Engl. J. Med. 1979, 301, 763–769. [Google Scholar] [PubMed]
  193. Anderson, S.D.; Daviskas, E. The airway microvasculature and exercise induced asthma. Thorax 1992, 47, 748–752. [Google Scholar] [CrossRef] [PubMed]
  194. Strauss, R.H.; McFadden, E.R., Jr.; Ingram, R.H., Jr.; Jaeger, J.J. Enhancement of exercise-induced asthma by cold air. N. Engl. J. Med. 1977, 297, 743–747. [Google Scholar] [CrossRef] [PubMed]
  195. Katelaris, C.H.; Carrozzi, F.M.; Burke, T.V.; Byth, K. A springtime Olympics demands special consideration for allergic athletes. J. Allergy Clin. Immunol. 2000, 106, 260–266. [Google Scholar] [CrossRef] [PubMed]
  196. Taudorf, E.; Moseholm, L. Pollen count, symptom and medicine score in birch pollinosis. A mathematical approach. Int. Arch. Allergy Appl. Immunol. 1988, 86, 225–233. [Google Scholar] [CrossRef] [PubMed]
  197. Fanger, P.O. Thermal Comfort. Analysis and Application in Environment Engineering; Danish Technical Press: Copenhagen, Denmark, 1970. [Google Scholar]
  198. Landsberg, H.E. The Assessment of Human Bioclimate, a Limited Review of Physical Parameters; World Meteorological Organization, Technical Note No. 123, WMO-No. 331; World Meteorological Organization: Geneva, Sweden, 1972. [Google Scholar]
  199. Driscoll, D.M. Thermal comfort indexes. Current uses and abuses. Nat. Weather Digest 1992, 17, 33–38. [Google Scholar]
  200. Hot Environments; Estimation of the Heat Stress on Working Man, Based on the Wbgt-Index (Wet Bulb Globe Temperature); ISO 7243; International Organisation for Standardisation: Geneva, Sweden, 1989.
  201. Yaglou, C.P.; Minard, D. Control of heat casualties at military training centers. AMA Arch. Ind. Health 1957, 16, 302–316. [Google Scholar] [PubMed]
  202. American College of Sports Medicine. Prevention of Thermal Injuries during Distance Running—Position Stand. Med. Sci. Sports Exerc. 1984, 16, ix–xiv. [Google Scholar]
  203. International Organisation for Standardisation. Ergonomics of the Thermal Environment—Determination and Interpretation of Cold Stress When Using Required Clothing Insulation (IREQ) and Local Cooling Effects; ISO 11079; International Organisation for Standardisation: Geneva, Sweden, 2007. [Google Scholar]
  204. Bahr, R.; Reeser, J.C. New guidelines are needed to manage heat stress in elite sports—The federation internationale de volleyball (FIVB) heat stress monitoring programme. Br. J. Sports Med. 2012, 46, 805–809. [Google Scholar] [CrossRef] [PubMed]
  205. Thorsson, S.; Honjo, T.; Lindberg, F.; Eliasson, I.; Lim, E.M. Thermal comfort and outdoor activity in Japanese urban public places. Environ. Behav. 2007, 39, 660–684. [Google Scholar] [CrossRef]
  206. Büttner, K. Physikalische Bioklimatologie. Probleme Und Methoden; Akademische Verlagsgesellschaft: Leipzig, Germany, 1938. [Google Scholar]
  207. Brocherie, F.; Girard, O.; Pezzoli, A.; Millet, G.P. Outdoor exercise performance in ambient heat: Time to overcome challenging factors? Int. J. Hyperth. 2014, 30, 547–549. [Google Scholar] [CrossRef] [PubMed]
  208. Weihs, P.; Staiger, H.; Tinz, B.; Batchvarova, E.; Rieder, H.; Vuilleumier, L.; Maturilli, M.; Jendritzky, G. The uncertainty of UTCI due to uncertainties in the determination of radiation fluxes derived from measured and observed meteorological data. Int. J. Biometeorol. 2012, 56, 537–555. [Google Scholar] [CrossRef] [PubMed]
  209. Fanger, P.O. Thermal Comfort; McGraw-Hill: New York, NY, USA, 1972. [Google Scholar]
  210. Ergonomics of the Thermal Environment—Analytical Determination and Interpretation of Heat Stress Using Calculation of the Predicted Heat Strain; ISO 7933; International Organisation for Standardisation: Geneva, Sweden, 2004.
  211. Jendritsky, G. Bioklimatische bewertungsgrundlage der räume am beispiel von mesoskaligen bioklimakarten. In Methode. zur Raumbezogenen Bewertung der Thermischen Komponente im Bioklima des Menschen (Fortgeschriebenes Klima-Michel-Modell); Jendritsky, G., Schirmer, H., Menz, G., Schmidt-Kessen, W., Eds.; Beiträge: Hannover, Germany, 1990; pp. 7–69. [Google Scholar]
  212. Jendritsky, G.; de Dear, R. Adaptation and thermal environmen. In Biometeorology for Adaptation to Climate Variability and Change. Biometeorology 1; Ebi, K.L., Burton, I., McGregor, G.R., Eds.; Springer: Berlin, Germany, 2009; pp. 9–32. [Google Scholar]
  213. Jendritsky, G.; Maarouf, A.; Fiala, D.; Staiger, H. An update on the development of a universal thermal climate index. In Proceedings of the 15th Conference on Biometeorology/Aerobiology and 16th International Congress of Biometeorology, Kansas City, MO, USA, 27 October–1 November 2002.
  214. Richards, M.; Havenith, G. Progress towards the final utci model. In Proceedings of the 12th International Conference on Environmental Ergonomics, Biomed, Ljubljana, Slovenia, 19–24 August 2007.
  215. Havenith, G.; Fiala, D.; Blazejczyk, K.; Richards, M.; Brode, P.; Holmer, I.; Rintamaki, H.; Benshabat, Y.; Jendritzky, G. The UTCI-clothing model. Int. J. Biometeorol. 2012, 56, 461–470. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  216. Fiala, D.; Lomas, K.J.; Stohrer, M. Dynamic simulation of human heat transfer and thermal comfort. In Proceedings of the 12th International Conference on Environment Ergonomics, Piran, Slovenia, 19–24 August 2007.
  217. Psikuta, A.; Richards, M.; Fiala, D. Single-sector thermophysiological human simulator. Physiol. Meas. 2008, 29, 181–192. [Google Scholar] [CrossRef] [PubMed]
  218. Jendritzky, G.; Havenith, G.; Weihs, P.; Batchvarova, E.; de Dear, R. The universal thermal climate index UTCI—Goal and state of cost action 730 and ISB commission 6. In Proceedings of the 18th International Congress Biometeorology ICB, Tokyo, Japan, 22–26 September 2008.
  219. Mateeva, Z.; Enache, L.; Mateeva, N. Bioclimatic effects on man and their assessment for the purposes of recreation and tourism. J. Int. Sci. Publ. Ecol. Saf. 2009. ISSN 1313–2563. [Google Scholar]
  220. Shitzer, A.; Tikuisis, P. Advances, shortcomings, and recommendations for wind chill estimation. Int. J. Biometeorol. 2012, 56, 495–503. [Google Scholar] [CrossRef] [PubMed]
  221. Brode, P.; Fiala, D.; Blazejczyk, K.; Holmer, I.; Jendritzky, G.; Kampmann, B.; Tinz, B.; Havenith, G. Deriving the operational procedure for the universal thermal climate index (UTCI). Int. J. Biometeorol. 2012, 56, 481–494. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  222. Psikuta, A.; Fiala, D.; Laschewski, G.; Jendritzky, G.; Richards, M.; Blazejczyk, K.; Mekjavic, I.; Rintamaki, H.; de Dear, R.; Havenith, G. Validation of the fiala multi-node thermophysiological model for UTCI application. Int. J. Biometeorol. 2012, 56, 443–460. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  223. Shitzer, A.; de Dear, R. Inconsistencies in the “new” wind chill chart at low wind speeds. J. Appl. Meteorol. Climatol. 2006, 45, 787–790. [Google Scholar] [CrossRef]
  224. Tikuisis, P.; Osczevski, R.J. Dynamic model of facial cooling. J. Appl. Meteorol. 2002, 41, 1241–1246. [Google Scholar] [CrossRef]
  225. Tikuisis, P.; Osczevski, R.J. Facial cooling during cold air exposure. BAMS 2003, 84, 927–934. [Google Scholar] [CrossRef]
  226. World Meteorological Organization, United Nations Environment Programme. Integrated Assessment of Black Carbon and Tropospheric Ozone: Summary for Decision Makers; UNON/Publishing Services Section: Nairobi, Kenya, 2011. [Google Scholar]
  227. World Health Organization. Global Solar UV Index: A Practical Guide; A Joint Recommendation of World Health Organization, World Meteorological Organization, United Nations Environment Programme and the International Commission on Non-Ionizing Radiation Protection World Health Organization (WHO): Geneva, Sweden, 2002. [Google Scholar]
  228. Maw, G.J.; Boutcher, S.H.; Taylor, N.A. Ratings of perceived exertion and affect in hot and cool environments. Eur. J. Appl. Physiol. Occup. Physiol. 1993, 67, 174–179. [Google Scholar] [CrossRef] [PubMed]
  229. Huizenga, C.; Hui, Z.; Arens, E. A model of human physiology and comfort for assessing complex thermal environments. Build. Environ. 2001, 36, 691–699. [Google Scholar] [CrossRef]

Share and Cite

MDPI and ACS Style

Brocherie, F.; Girard, O.; Millet, G.P. Emerging Environmental and Weather Challenges in Outdoor Sports. Climate 2015, 3, 492-521.

AMA Style

Brocherie F, Girard O, Millet GP. Emerging Environmental and Weather Challenges in Outdoor Sports. Climate. 2015; 3(3):492-521.

Chicago/Turabian Style

Brocherie, Franck, Olivier Girard, and Grégoire P. Millet. 2015. "Emerging Environmental and Weather Challenges in Outdoor Sports" Climate 3, no. 3: 492-521.

Article Metrics

Back to TopTop