Domestic dogs interlink with every aspect of human society, from companions to those working and providing assistance. Many of these roles depend on physical activity. Dog walking and canine sport participation are important components of the human–canine bond for pet dogs, whilst guiding, searching and even combat comprise key elements of assistance and service dogs’ duties. Extreme environmental conditions, particularly heat stress, affect both the performance ability and overall health of dogs, with heat-related illness reported to be the one of the most common causes of death for military working dogs [1
]. Physical activity is a leading trigger of heat-related illness (HRI) in pet dogs living in the UK [2
] and Israel [3
]. Therefore, rising global temperatures have the potential to severely alter dogs’ roles in human society, posing a serious risk to both canine health and the human–canine bond, and thus canine welfare. Improving our understanding of this phenomenon has the potential to mitigate against harm, especially in an increasingly unpredictable environment [4
Dog ownership likely has positive effects for owners. These include improvement in physical and mental health [5
], including reduced depression, increased levels of oxytocin and decreased blood pressure and cholesterol levels [7
]. Dogs also promote owners to exercise regularly, which decreases the risk of cardiovascular disease for both individuals [8
]. Social contact amongst owners is facilitated by their dogs and decreases the feeling of loneliness [8
]. Exercising with their owner is likely the primary source of exercise for a companion animal and so largely depends on owner-related factors such as their physical and social environment, own capabilities, preferences, motivations towards exercise and relationship with their dog [10
]. In general, older adults are less likely to exercise in poor weather conditions, preferring warmer, dry days [11
]. Ice, snow and rain have all been cited as reasons not to exercise in adults [12
]. Dog owners also cited weather as a reason for reducing the frequency and duration of walks [13
]. However, dog owners were more physically active than non-owners in poor weather conditions [14
] when dog walking shifted from recreational to functional to fulfil the dog’s need for stimulation and exercise [15
]. Whilst dog owners walk more times per week than non-owners, fewer than half of dog owners walk for a sufficient duration to obtain the recommended minimum of 150 min of moderate exercise a week [16
]. Owners and dogs that share an active lifestyle complement each other, which results in high owner satisfaction [18
]; owners that consider their dog to provide motivation and social support walk with them more frequently [19
Dog walking also provides health benefits to dogs. Around half of the UK dog population is considered to be overweight or obese [20
] and whilst diet is a major factor, exercise is also important. Overweight dogs receive, on average, fewer and shorter walks than dogs in ideal body condition [22
]. Canine obesity is of increasing concern due to the risk of chronic diseases and reduction in the dog’s quality of life [24
]. Increased exercise and dietary adjustments are the primary and most efficient methods of canine weight management [26
]. Therefore, additional barriers to exercise such as weather conditions could potentially exacerbate the canine obesity epidemic.
Whilst studies have explored the impact of adverse, wet or wintery weather on owner’s frequency and duration of dog walks, there is a lack of information as to owners perceptions of their dogs’ ability to cope with seasonal weather variation. This includes both hot and cold extremes and how they impact on canine exercise levels. Additionally, previous studies mainly focus on dog walking as the form of canine activity; there are limited data available regarding the wider types of exercise undertaken. Hall et al. [2
] identified that exercise is responsible for almost three quarters of all HRI cases in UK dogs, and over a third of brachycephalic dog owners report concerns about overheating [27
]. Both brachycephalic dogs and obese dogs are at greater risk of developing HRI [28
], raising concerns that the changing demographic of the pet dog population (rising levels of obesity and increasing popularity of brachycephalic breeds) could further negatively impact canine activity levels as climate change increases the frequency of seasonal weather variations. If dogs are to retain their many roles in human society, a better understanding of the impact weather extremes have on canine activity is needed.
This study aimed to explore dog-owner perceptions of the effects of both summer and winter weather on their dog’s activity levels. Using analysis of an international survey of dog-owners, we aimed to explore how canine factors such as breed, age, sex and skull shape influenced owner perceptions and the use of mitigation strategies to continue activity in adverse weather (e.g., dog coats and cooling strategies). An additional aim of this study was to report the variety of activities, and duration of activity regularly undertaken by owned dogs.
This study reports owner perceptions of their dog’s routine activity levels and how seasonal weather extremes (summer and winter) and canine factors impact upon them. Dog owners’ use of mitigation actions such as canine coats, cooling aids and post-exercise cooling are also reported. Dependent on current practices, these could form the basis of educational campaigns to support adaptive responses to seasonal weather variations in order to maintain canine activity. It is important to distinguish that whilst previous studies have looked at the impact of weather conditions as a factor affecting owner desire to walk and subsequent effects on owner activity levels, this study focused on the perceived impact of weather on the dog’s activity levels, including both activity associated with the owner and activity independent of the owner.
Whilst the level of exercise required by a dog varies according to a number of factors (e.g., breed; age; health status; size), it is recommended that even the smaller breeds (e.g., Chihuahuas and Papillons) receive at least 30 min of exercise a day, split over a number of sessions [23
]. Pickup et al. [23
] reported that whilst there are no evidence-based guidelines on individual breed exercise requirements, only 50% of dogs surveyed received the Kennel Club recommended daily activity for that breed. In the present study, only 39.2% of adult dogs from the breeds reviewed met the recommended daily activity, with fewer than 6% of Golden Retrievers and no Rottweilers achieving the recommendation. Larger and energetic breeds are more likely to be walked for longer [32
]. However, the findings of this study show that 10.8% of the dogs surveyed received less than 30 min of exercise per day and 27.1% were only active for a single period.
Typically, the activity levels of family dogs are largely controlled by owners and result in just one period of higher-intensity daily activity. Conversely, farm dogs and free-roaming dogs display two distinct periods of activity with longer duration, but lower intensity. [10
]. This finding is reflected in the present study, over half of the dogs surveyed completed high intensity exercise on a daily basis. The most frequently selected daily activity for the dogs in the current study was walking off lead (64.4%) followed by running off lead (59.9%) then walking on lead (47.7%). Fetch and retrieving activities featured as a daily (42.4%) or frequent (at least monthly) activity for 75.3% of dogs. Retrieving activities, particularly ball throwing, can be used as a means of exercising dogs with limited requirement for the owner to move [8
]; however, concerns have been raised regarding the impact of repetitive ball throwing both behaviourally and due to the potential for repetitive strain injuries [33
] and exacerbation of osteoarthritis [34
As the majority of pet dogs are not receiving the recommended levels of daily activity, and around half of the UK pet dog population is reported to be overweight [20
], it is concerning that over 80% of survey respondents in the present study reported that hot summer weather reduced both the duration and vigour of their dog’s activity. Due to the subject of the survey, it is probable that the participants are more engaged with their dog’s activity levels, meaning these results likely reflect a population of dogs that are more active than the general population. Less active dogs will suffer greater impacts of extreme heat, as reduced activity impairs thermoregulation during exercise [35
]. As global temperatures increase further, this finding suggests that the majority of pet dogs will experience reduced activity levels due to hot weather. Obese dogs are at greater risk of HRI [28
], including specifically increased risk for exertional HRI [2
], creating a potentially lethal spiral of rising temperatures resulting in more obese dogs that are at greater risk of exertional HRI when they do manage to exercise. It is perhaps unsurprising that many dog owners are already reporting using mitigation actions to continue exercising their dogs in hot weather.
The summer CAS variable attempted to measure owner perceptions of the impact extreme summer weather (heat and humidity) has on canine activity, with higher summer CAS scores inferring greater negative impacts on the dog’s ability/willingness to exercise in hot weather. The variables skull shape, bodyweight, sports participation, sex/neuter, daily exercise, and continent were found to be associated with summer CAS. At univariable levels, three breeds (Pointer (English), Collie and Springer Spaniel) were found to have lower scores, and three breeds (Boxer, French Bulldog and Staffordshire Bull Terrier) were found to have higher scores compared to Labrador Retrievers. This result is concerning, as Springer Spaniels and Collies were previously found to be at greater risk of exertional HRI than Labrador Retrievers in UK dogs presenting to veterinary clinics with HRI [2
]. This suggests there may be a mismatch between the owner’s perception of their dog’s ability to exercise in hot weather and the dog’s actual thermoregulatory ability. Conversely, male neutered dogs were considered to have higher summer CAS compared to female entire dogs, which reflects the findings of Hall et al. [2
], that male neutered dogs had the greatest odds for exertional HRI, and studies report higher post-exercise body temperatures in male dogs compared to females [36
]. Dogs active for 120 min or more each day were considered to have lower summer CAS compared to dogs completing less than 10 min per day. This could be because dogs completing over 120 min of daily activity are exercising less intensely and are therefore less affected by heat. Alternatively, the most active dogs are simply physically fitter, and able to better tolerate exercise in hot environments. As improved fitness has been found to improve thermoregulation during exercise [35
], the latter is potentially more likely.
Dogs living in Australia were considered to have lower summer CAS compared to dogs living in Europe. Whilst the number of survey respondents from Australia compared to Europe must be considered here, this result is somewhat unexpected given the prolonged summer heat experienced by much of the continent and increasingly frequent extreme heat events. This finding could indicate a mismatch between Australian owners’ perceptions of their dog’s ability to exercise in the heat, and the dog’s actual tolerance of summer conditions. Reports of animals left in hot cars in Australia increased year on year from 2008 to 2018 [38
], with suggestions that owners of adult dogs may imagine that their dog is more able to tolerate heat than they actually are. Given the increasing frequency of extreme heat events in this region, these findings suggest further research into owner awareness of heat-related illness is urgently needed.
The results of the present survey suggest that hot weather is already negatively impacting canine activity levels, so mitigation strategies may be important to increase activity and reduce obesity. This is especially important given that temperatures are likely to increase in the near to long term. Over 90% of dog owners in the present study reported carrying water or exercising in close proximity to water to facilitate dog activity in the summer. Additionally, 23.7% of respondents reported that their dog swims outdoors at least once a week as a baseline. Two other mitigation actions for exercising dogs in hot weather were explored in the present study. Over half of the respondents agreed that they regularly cool their dog after activity in hot weather, with skull shape, dog age, daily activity levels and canine sport participation identified as factors associated with this practice. Notably, owners of French Bulldogs had almost eight times the odds for post-exercise cooling compared to owners of Labrador Retrievers, and owners of dogs participating in canine sports had 1.45 times the odds for post-exercise cooling use compared to non-sporting dog owners. French Bulldogs have been found to have increased risk of exertional HRI [2
], so this increased use of cooling aids could simply reflect owners’ awareness of their dog’s thermoregulatory problems. However, social influences such as fashion and media attention are thought to have had a role in the soaring popularity of this breed [39
], with their distinctive appearance making them popular with users of social media despite their many health problems [42
]. The increased use of cooling aids amongst both French Bulldog owners and sports dog owners could similarly reflect the influence of social media, with owners sharing management tips and photos of their dogs using such devices to breed/sport groups and sharing anecdotal evidence of their effectiveness. Owners of dogs aged under 2 years old and dogs active for 120 min or more per day had the highest odds for post-exercise cooling, likely reflecting the high-energy behaviour of young, fit and active dogs and their increased risk of exertional HRI compared to older animals [2
]. This finding is positive, suggesting that awareness of the risk of HRI following exercise is improving amongst dog owners, but as exercise is the leading trigger of HRI in dogs [2
], continued owner education is essential. Historically, concerns were raised regarding the use of cold water for cooling dogs affected by HRI and myths persist that promote the use of ineffective cooling methods such as putting alcohol on paws [43
]. However, both human and canine studies have shown that evaporative cooling using (preferably cold) water and air movement or cold water immersion are the most effective methods of cooling dogs in an emergency situation [44
Only a quarter of the survey respondents reported using a cooling aid such as a cooling coat to facilitate dog activity in hot weather. Owners of dogs participating in canine sports, and brachycephalic dogs both had around two times the odds for cooling aid use compared to non-sporting dogs and mesocephalic dogs, respectively. These results support the findings reported by Packer et al. [27
], that over a third of brachycephalic dog owners recognized that their dog had a problem with heat regulation. Not only are owners of brachycephalic dogs more likely to recognize thermoregulation problems (brachycephalic dogs were also considered to have higher summer CAS), they also appear to be more likely to utilize cooling aids such as cooling coats to facilitate activity in summer. This is concerning, as there is a paucity of peer-reviewed evidence relating to the effectiveness of canine cooling coats, and similar cooling aids (moistened multilayer breathable fabric coats) have been found to be ineffective when used on exercising horses [49
]. Continued use of ineffective cooling aids could inadvertently put more dogs at risk of HRI, if owners believe the use of such devices could mitigate hot weather that would otherwise prevent them from exercising their dog.
Owners of dogs competing in canine sports reported significantly lower winter CAS, suggesting their dogs were less likely to experience activity disruption due to wet and cold weather. Whilst they also reported significantly reduced summer CAS, they were also more likely to cool their dog after exercise in hot weather and use cooling aids (such as cooling coats) to facilitate exercise in hot weather. Previous studies have reported dog owner motivations for competing in canine sports, including connection to the dog, physical activity for the dog and owner, and the learning and enjoyment that comes from training [50
]. Owners of dogs participating in sports may be less likely to neuter their dog [51
], which could explain why neutered dogs tended to have higher winter CAS scores than entire dogs. Perhaps unsurprisingly, obesity levels in dogs competing in canine sports were lower than pet dogs not participating in sports in a study by Kluess et al. [51
]. This was attributed to better owner awareness of body condition scoring, lower overall rations fed and fewer treats fed, and higher levels of engagement with activities that required owner involvement. The results from the present study add further evidence to sports-dog owners having increased motivation to exercise, even in poor weather, and suggest that sports-dog owners may be more aware of the potential risk associated with canine activity—notably HRI—and have better awareness of the mitigation actions that can be employed to maintain activity in hot weather. As early cooling has been found to improve survival in dogs affected by HRI [52
], improving owners’ ability to recognize early signs of HRI and dispelling myths associated with effective cooling methods (notably outdated concerns relating to the use of cold water) should be considered educational priorities for dog owners in the face of rising global temperatures [53
As previously reported, inclement winter weather conditions can reduce owner motivations to exercise their dog [54
]. The present study found that owners considered their dog’s activity to be reduced by icy conditions (64.0%) more than cold (48.2%) or rain (25.3%). These findings likely reflect the owner’s willingness to brave winter weather conditions more than the dog’s willingness, as previous studies have reported that neither rain nor snow had a noticeable impact on free-roaming urban dogs, with dog activity increasing in response to cloud cover [55
]. Whilst rain increased exercise levels for almost a fifth of dogs (19.8%), cold and ice had little positive impact on increasing exercise in any of the dogs (2.6% and 3.1%, respectively). Whilst icy conditions are less common than other winter weather, they are arguably harder to mitigate in terms of likelihood to slip, fall or receive a pad injury.
Half of owners reported using a coat on their dog in winter to continue exercising, with owners of breeds with less body fat (Greyhound and Whippet), thinner coats (Pointer and Boxer) and small breeds (Chihuahua, Cavalier King Charles Spaniel and Pug) most likely to use them. The dogs considered to have the lowest winter CAS (and therefore more likely to exercise more in cold, wet and icy weather) were those with a normal exercise period of 60 min or more. This means that dogs with the shortest regular activity duration are more likely to miss out on opportunities to exercise in the winter, when it is potentially safest for them to do so. In addition, older dogs (>8 years) were considered to be more negatively affected by adverse weather than those over 2. Small dogs (under 10 kg) were considered to be more negatively affected by adverse weather, despite having the greatest odds for coat use in winter. Coat use may also be related to fashion and the anthropomorphism of small dogs [56
], rather than being purely functional to facilitate exercise.
Dogs with a brachycephalic skull shape and designer hybrids with a brachycephalic skull shape within the breeding had the greatest odds for coat use in winter. These dogs were also perceived to have higher winter CAS, meaning they likely experienced reduced activity opportunities in winter despite their coat use. Some brachycephalic breeds including Pugs and Cavalier King Charles Spaniels are reported to be at increased risk of being overweight [58
], meaning it is unlikely they need an additional coat in winter, and would in fact probably benefit from the additional activity, provided their respiratory function allows them to exercise safely [59
The perceptions of dog owners reported in the present study suggest increasing seasonal weather variation will have profound effects on the activity element of human–canine relationships in the future. With over 80% of owners reporting that hot and humid weather reduces their dog’s summer activity, global warming could seriously impact the way owners interact with their dogs, with lower levels of activity potentially worsening the canine obesity epidemic. Worryingly, there appears to be a disparity between some dog owners’ perceptions of their pet’s ability to exercise in hot weather, and the dog’s potential risk of HRI, and a quarter of the owners surveyed reported using cooling aids such as cooling coats to facilitate exercise despite there being no good evidence to support their effectiveness. As exercise is an important trigger of HRI [2
], it is vital that dog owners receive evidence-informed advice to support safe exercise practices in hot, summer weather. Free-roaming urban dogs and free-roaming owned dogs have been found to limit their activity to early mornings and later evenings to avoid the heat of the day in hot weather [10
], and similar patterns of dog walking and exercising need to be adopted by owners. However, having to rise early to exercise a pet dog may create a barrier to pet ownership, and pose particular challenges to women who walk alone due to the potential risk of being attacked if walking alone in lowlight conditions. Failure to adapt to rising global temperatures and allowing canine activity levels to drop risks a worsening of the canine obesity crisis with associated health impacts [26
], and potentially increased levels of behavioural issues [60
], which could lead to more dogs being relinquished for rehoming [62
The main limitation of this study relates to the use of a questionnaire and the use of self-reported data. There is a level of uncertainty in the accuracy of the results. In particular, it is well known that survey respondents tend to over-estimate the amount of activity they perform, which is likely also true for owner estimates of canine activity [5
]. Additionally, the study explored owner perceptions of the impact extreme weather had on canine activity, meaning the results are only as reliable as the owner’s perception and recollection of events. The survey method did not permit in-depth exploration of the conflict between owner perceptions of their dog’s ability or willingness to exercise in certain types of weather, and the dog’s actual ability or willingness to exercise in that weather. The results presented here report owner perceptions and are thus likely to be influenced by the owner’s underlying motives relating to their pet’s activity function. Survey participants were recruited via social media and the popular veterinary press, meaning the study likely selected for a demographic of dog owners more actively engaged with their pet’s health. Several large canine sports associations shared the survey, which may have increased the proportion of sport-dog owners in the study. As dog owners are known to be relatively poor at accurately assessing canine body condition score [51
], neither body condition score nor an assessment of bodyweight relative to breed was attempted, as the authors felt neither would be reliable measures. As overweight dogs have been found to have increased odds of HRI, future work should aim to address this omission. It was not possible to accurately collect underlying canine health data in the survey, so it is probable that some dogs had conditions that impacted their ability to exercise; however, it is unlikely that the study sample included an over-representation of dogs with underlying health conditions that would impact their ability to exercise, given the relatively high proportion of dogs regularly participating in sports.
The relatively large confidence intervals reported for the statistical models suggest the study is underpowered, and the low numbers of respondents from non-European countries limits the conclusions that can be drawn from analyses including location. Additionally, the reliance upon volunteers offering to translate the survey limited the potential for greater international distribution. Future work could directly measure canine activity levels over a full year to more accurately assess the impact of seasons and extreme weather, and work is urgently needed to assess the safety and efficacy of mitigation actions such as cooling coats to generate better evidence to support owner education.