Search Results (137)

Objectives: Methamphetamine (MA) abuse during adolescence can have a significant impact on brain development. On the other hand, regular exercise is known to promote brain health and may have neuroprotective effects. The purpose of this study is to compare brain volumes in three different adolescent groups: those with active methamphetamine use disorder (MUD), adolescent athletes who regularly exercise, and healthy control adolescents. Methods: This MRI study involved three groups of adolescents: 10 with active MUD (9 males, 1 female), nine licensed runner adolescents (three males, six females), and 10 healthy adolescents (5 males, 5 females). Brain volumes were analyzed using T1-weighted images from a 3.0 Tesla MRI scanner, and then segmented automatically with vol2Brain. Statistical analyses included ANCOVA with sex as a covariate and LSD post hoc tests performed using SPSS Statistics 23. Results: Adolescents with MUD showed a 10% increase in total white matter volume compared to the athlete group. Conversely, cortical gray matter volume was reduced by 4% compared to the healthy control group and by 7% compared to the athlete group. The frontal and insular cortices in the MUD group had significantly diminished volumes compared to the athlete group. Overall, individuals with MUD had decreased gray matter volumes and increased white matter volumes in their brains. The brain volumetric differences between the MUD group and the athlete group were statistically significant. Conclusions: The brains of those with MUD displayed a reduction in gray matter volume and an increase in white matter volume, indicating damage from MA on the developing adolescent brain. The volumetric disparities between the MUD and athlete groups were found to be significantly different, suggesting a possible neuroprotective factor of exercise. Further studies are required to explore the potential of exercise-based interventions in alleviating the harmful effects of MA abuse. Full article

Background: Female collegiate runners may be at high risk for disordered eating and poor bone health, which are characteristics of the female athlete triad. Intuitive eating can promote healthy eating behavior and adequate calorie intake, central variables in calculating energy availability, an underlying cause of low bone mass in athletes. Poor bone health can contribute to injury, preventing optimal performance for athletes. The purpose of this study was to assess intuitive eating, energy availability, and bone mineral density in female college runners with comparison to non-athletes. Methods: Female college athletes (n = 13, 19.5 ± 1.4 yrs) and non-athletes (n = 12, 19.9 ± 1.3 yrs) completed the Intuitive Eating Scale, Eating Disorder Examination Questionnaire, and menstrual history survey. Bone mineral density and body composition were measured using a dual-energy X-ray absorptiometer (DEXA). A 3-day diet record and exercise log were used to assess dietary intake, estimate energy expenditure, and calculate energy availability. Results: Intuitive eating was inversely correlated with disordered eating (r = −0.596, p = 0.002). Intuitive eating scores were not correlated to calorie intake, energy availability, bone mass, or percent body fat. Runners consumed significantly more calories, calcium, magnesium, phosphorus, and protein (g/kg) than non-athletes. Energy availability and bone mineral density were not significantly different between runners and non-athletes. Conclusions: Intuitive eating is associated with healthy eating behaviors in college-age females and was not related to energy availability, bone density, or body composition in this population. Future research could explore the use of intuitive eating principles in reducing disordered eating and addressing low energy availability in female runners and non-athletes. Full article

Breathing reserve (BR) is the remaining proportion of achievable minute ventilation that remains unutilized at total exhaustion during exercise. Previous studies have found a smaller BR in endurance-trained athletes compared to untrained controls. However, most of these studies have examined men. Given that women have a greater ventilatory limitation than stature-matched men, the present cross-sectional study aimed to investigate how this sex difference influences BR and lung function tests in endurance-trained females compared to matched, untrained females. To obtain further insight, we also aimed to investigate whether VO₂max serves as a predictor of BR. We examined 15 female elite runners and 15 healthy, matched female controls aged 24–33 years with regard to pulmonary function, MVV, V_Emax, BR, and VO₂max. The elite runner group had a median BR of 5%, while that of the controls was 21%, representing a significant difference. Lung function tests showed no differences between the two groups. A moderate association was found between VO₂max and BR. The female elite runners demonstrated a lower BR than the group of matched, untrained controls, which was lower than that found for male elite athletes in previous studies. This may indicate a greater ventilatory demand in female relative to male endurance athletes. Full article

With the global increase in women’s participation in running, understanding factors like footwear in performance and injury prevention has become essential. Minimalist shoes (MSs) and traditional shoes (TSs) influence muscle activation patterns, affecting running technique. Proper coordination of the core muscles is essential for efficient stride and posture. This study analyzed muscle activation in nulliparous women running in MSs and TSs at different speeds and explored the correlations with age and BMI. A crossover clinical trial assessed the EMG activation of the lumbar erector (LE), gluteus maximus (GM), pelvic floor, and internal oblique (IO) muscles during treadmill running at 6, 9, and 11 km/h. Fifty-one healthy women (26.55 ± 5.11 years; body mass index (BMI): 21.29 ± 2.07 kg/m²) participated. The protocol included a warm-up, 30 s runs at each speed, and a 5-minute washout between trials. The statistical analyses included Wilcoxon, Friedman, and Spearman’s correlation tests. GM and IO showed the highest activation (p < 0.001) regardless of the footwear or speed. No significant differences were found between MSs and TSs. Weak-to-moderate correlations emerged between BMI and LE muscle activation with MSs, and between BMI and IO with both footwear. Significant correlations were also found with IO activations, but none with PF muscles. The correlations between personal variables, shoe types, and muscle activation suggest that individual and external factors may influence neuromuscular modulation, impacting injury prevention and personalized interventions. Full article

Background: Running-related injuries are often associated with biomechanical inefficiencies, particularly in the sagittal and frontal planes. This study evaluates the effects of three interventions—reduced heel-to-toe drop (HTD) shoes, increased cadence, and inversion foot orthoses—on key kinematic parameters: ankle dorsiflexion, knee flexion, and hip adduction (measured at foot strike and at their respective peak joint angles during the stance phase). Methods: Nineteen recreational runners (ten males and nine females; mean ± SD: age 26.4 ± 4.3 years; height 174.2 ± 7.8 cm; weight 68.3 ± 9.6 kg; BMI 22.5 ± 2.1 kg/m²) participated in a 3D motion capture study under five experimental conditions: baseline (10 mm HTD, no cadence adjustment, no foot orthoses), full intervention (5 mm HTD, +10% cadence, orthoses), and three partial interventions: HTD combined with orthoses, HTD combined with increased cadence, and cadence increase alone. Kinematic changes were analyzed for statistical significance. Results: The full intervention significantly increased ankle dorsiflexion at foot strike (from 8.11° to 10.44°; p = 0.005) and reduced peak knee flexion (from 45.43° to 43.07°; p = 0.003). Cadence adjustments consistently produced improvements, while orthoses and HTD alone showed effects on ankle flexion only. Conclusions: Combining structural (HTD and orthoses) and dynamic (cadence) modifications optimizes running biomechanics, providing evidence-based strategies for injury prevention and performance enhancement. Full article

This study aimed to explore the occurrence of exercise-associated gastrointestinal symptoms (ExGIS) in collegiate athletes and identify related self-management practices. A sequential mixed methods design was used, consisting of an online survey followed by semi-structured interviews. Data were analyzed with descriptive statistics (survey) and thematic analysis (interviews). Survey respondents (n = 96) represented various individual and team sports but were primarily female (76%). ExGIS prevented or interrupted training and/or competition in 32%. Female athletes experienced gastrointestinal symptoms (GIS) more frequently at rest (60%) and during training (37%), compared to males (22% and 9%, respectively; p < 0.01). Only 12% sought health care for ExGIS. Four (13%) female runners with ExGIS agreed to an interview. Response rates and interview data provided evidence of stigma in discussing GIS. Self-imposed food restriction was a common self-management strategy. In summary, female collegiate athletes may experience a greater burden of GIS and ExGIS than males. The stigmatized topic of ExGIS is a potential barrier to seeking health care and support. Access to a sport dietitian could help to address barriers to ExGIS care and support self-management practices in these athletes. Full article

Objectives/Background: This study investigated the influence of acid–base and electrolyte balance on the performance of female athletes in a 45 km ultramarathon. The aim was to analyze the impact of these variables on performance, particularly in athletes with varying completion times. Methods: Nineteen female athletes (mean age: 35.9 ± 6.5 years) were divided into three groups based on their race completion times: faster, intermediate, and slower. Blood samples were collected before and after the race to assess biochemical variables and arterial blood gases. Results: Significant differences in potassium (K⁺) levels were found in the intermediate (p = 0.003, adjusted p = 0.01) and slower (p = 0.006, adjusted p = 0.03) groups. Hematocrit (Hct) showed a significant reduction in the intermediate group (p = 0.007, adjusted p = 0.04). In arterial blood gas variables, significant reductions in HCO₃⁻ and pCO₂ were observed in the faster (HCO₃⁻: p = 0.002, adjusted p = 0.008; pCO₂: p = 0.007, adjusted p = 0.02) and intermediate (HCO₃⁻: p = 0.005, adjusted p = 0.02) groups. In the slower group, significant reductions in pH (p = 0.001, adjusted p = 0.004) and HCO₃⁻ (p = 0.001, adjusted p = 0.004) were found. The correlation between post-race Na⁺ levels and performance was significant in the intermediate group (p = 0.01, adjusted p = 0.02). Conclusions: Acid–base and electrolyte imbalances significantly affect ultramarathon performance, with a greater impact observed in athletes with slower times. These findings highlight the importance of strategies to optimize electrolyte and acid–base balance in endurance events. Full article

Background: Patellofemoral pain (PFP) is one of the most common multifactorial musculoskeletal pathologies affecting the knee joint. The prevalence of PFP in the general population ranges from 11% to 17%, with higher rates observed in specific groups such as females, runners, military personnel, and young athletes. To assess symptoms associated with PFP, the patellofemoral subscale (KOOS-PF) was developed, consisting of 11 questions that evaluate pain, stiffness, and quality of life. The KOOS-PF scale has already been validated and shown to be reliable in both its Spanish and Arabic versions. Objectives: The aim of this study was to assess the reliability and validity of the KOOS-PF scale in the Greek language among the Greek population with patellofemoral pain. Methods: Fifty-five participants aged 18–65 years who suffered from PFP were evaluated in two phases on the first and third days to determine the reliability and validity of the measures of KOOS-PF in the Greek language. Construct validity was assessed using the knee outcome survey scale—activities of daily living scale (KOS-ADLS). Reliability was measured through repeated measurements (test–retest) using intraclass coefficient correlation (ICC), standard error of measurement (SEM), and smallest detectable difference (SDD). Internal consistency was evaluated using Cronbach’s coefficient a. The significance level was set at 5% (α = 0.05). Results: The KOOS-PF measures showed high internal consistency reliability (Cronbach’s alpha 0.87, p = 0.05) and high test–retest reliability (ICC = 0.95, p = 0.05, SEM = 3.7, SDC = 13.57). Additionally, the Greek version of the KOOS-PF exhibited high construct validity when correlated with the KOS-ADLS scale (r = 0.72, p = 0.001). Conclusions: The KOOS-PF scale displayed high reliability and construct validity for measuring patellofemoral pain in the Greek population. Full article

The purpose of this study was to compare the mechanical properties of a non-cushioned minimalistic shoe and cushioned shoe during walking at 6 and running at 10 and 14 km∙h⁻¹ in habituated female runners. Twelve habituated female runners completed two trials (cushioned shoe vs. minimalist shoe) with three within-trial speeds (6, 10, and 14 km∙h⁻¹) in a counter-balanced design. Flexible pressure insole sensors were used to determine kinetic variables (peak vertical impact force, average loading rate, active vertical peak force, time to active peak vertical force, and impulse) and spatiotemporal variables (stride duration, cadence, ground contact time, swing time, and time to midstance). Cushioned running shoes exhibited greater energy absorption (690%), recovered energy (920%), and heat dissipation (350%). The cushioned shoes significantly reduced peak vertical impact (~12%) and average loading rate (~11%) at running speeds 10–14 km∙h⁻¹. However, these effects were not observed during walking, nor did the cushioned shoes influence peak active force, impulse, stride duration, ground contact or swing time. Cushioned running shoes provide significant benefits in energy absorption, energy recovery, and heat dissipation, which decrease impact-related forces and loading rates in female runners without changing the spatiotemporal variables of gait. Full article

Objective: This study aims to evaluate the effects of a 20-week endurance and strength training program on running economy and physiological, spatiotemporal, and neuromuscular variables in trained runners. Methods: A total of 18 runners (13 males and 5 females) completed a running economy test (2 bouts of 5 min at 3.06 m·s⁻¹ for females and at 3.61 m·s⁻¹ for males) and a graded exercise test (5 min at 2.78 m⋅s⁻¹, with speed increasing by 0.28 m⋅s−1 every 1 min until volitional exhaustion). During the training program, the participants completed different low-intensity continuous running sessions, high-intensity interval running sessions, and auxiliary strength training sessions. Results: Running economy, measured as oxygen cost and energy cost, increased by 4% (p = 0.011) and 3.4% (p = 0.011), respectively. Relative maximal oxygen uptake (VO_2max) increased by 4.6%. There was an improvement in the speed associated with the first (VT₁) and the second ventilatory threshold and with the maximal aerobic speed by 9.4, 3.7, and 2.8% (p = 0.000, p = 0.004, and p = 0.004, respectively). The %VO_2max value of VT₁ increased by 4.8% (p = 0.014). Conclusions: These findings suggest that a 20-week endurance and strength training program significantly improves performance and physiological factors without changing the runner’s biomechanics. Full article

Treadmill running simulates various conditions, including flat, uphill, and downhill gradients, making it useful for training and rehabilitation. This study aimed to examine how incline and decline treadmill running affect local dynamic stability of individual running movement components that cooperatively contribute to achieving the running tasks. Principal component analysis (PCA) was used to decompose movement components, termed principal movements (PMs), from kinematic marker data collected from 19 healthy recreational runners (9 females and 10 males, 23.6 ± 3.7 years) during treadmill running at 10 km/h across different gradients (−6, −3, 0, +3, +6 degrees). The largest Lyapunov exponent (LyE) of individual PM positions (higher LyE = greater instability) was analyzed using repeated-measures ANOVA to assess treadmill gradient effects across PMs. The results showed that the effects of treadmill gradient appear in PM₃, which corresponds to the mid-stance phase of the gait cycle. Specifically, decline treadmill running significantly decreased local dynamic stability (greater LyE) compared to equivalent incline conditions (p ≤ 0.005). These findings suggest that decline treadmill running should be used cautiously in rehabilitation settings due to its potential to reduce an ability to control and respond to small perturbations, thereby increasing the risk of instability during the weight-bearing support phase of gait. Full article

Despite strength training (ST) being well characterized by professional runners, little is known about the inclusion of ST models for recreational runners. Thus, the present study aimed to investigate the presence of ST in the training practices of recreational runners, with a focus on understanding its characteristics and the motivations of recreational athletes for including ST in their routines. To this end, 801 recreational runners (493 male and 308 female) completed a structured questionnaire regarding their training habits, the inclusion of ST, and its characteristics, concerning the type of ST, training volume, and the reasons for including ST in their training programs. To assess the possible associations between categorical variables, data were analyzed using the chi-square test for independent samples. Approximately 625 runners (78.1%) reported that they included ST in their training routine, with a statistically significant difference between the sexes (men: 73.5% vs. women: 85.4%; X² = 14.09; p = 0.01). Traditional strength training (TST) was the predominant type of ST included (78.5%), with most participants performing 2–4 sets and 8–12 repetitions per set at a frequency of 3–4 sessions per week. The importance of ST was primarily attributed to performance improvement (85%). The results suggest that recreational runners incorporate different types of ST into their training routines, with TST being the predominant type perceived by runners as a valuable asset for improving running performance. Full article

We recently have shown that the gut microbiota composition in female and male runners positively correlates with sports, and female runners show similar gut microbiome diversity to male runners. However, gut microbiota composition has not yet been fully investigated in other endurance athletes, such as cyclists. Therefore, in the current study, we investigated the gut microbiome profiles in competitive, non-professional female and male cyclists compared to what we have shown in runners. We aim to understand (1) whether the gut microbiome signature is sport-specific; (2) whether there is a microbiome difference between female and male cyclists and runners; and (3) whether the gut bacteria expressed in cyclists and runners correlates with exercise performance. Our study included 58 subjects: 18 cyclists (9 males), 22 runners (13 males), and 18 control subjects (9 males). Fecal samples were obtained and subjected to taxonomic analysis to assess the relative abundances of species across subjects based on 16S rRNA sequencing results. Both alpha and beta diversity of the bacterial communities were evaluated to identify compositional variations between the groups. Each participant completed a maximal oxygen consumption test and a time-to-exhaustion test at 85% of the measured VO2max. Cyclists performed the test on an SRM ergometer, while runners used a motorized treadmill. Blood lactate levels were measured at 5 min intervals throughout the time-to-exhaustion trials. Alpha diversity demonstrated a significant difference (p-adj < 0.001) between cyclists and runners. Male cyclists showed significantly lower alpha diversity than runners (p-adj < 0.001). The taxonomic analysis of gut microbiota composition between cyclists, runners, and controls showed a lower or higher abundance of fifteen different bacteria. In cyclists, there was a significant positive correlation between six bacteria, and in runners, there was a significant positive correlation between eight bacteria, with weekly training volume, time-to-exhaustion, VO2max, and blood lactate levels. This study suggests potential sport-specific characteristics in long-distance cyclists’ and runners’ gut microbiome signatures. These findings emphasize the differences in gut microbiota between cyclists and runners, probably due to the difference in physiological and biomechanical conditions related to the activity mode during each sport. Full article

Previous studies on gender differences in running biomechanics have predominantly been limited to joint angles and have not investigated a potential influence of footwear condition. This study shall contribute to closing this gap. Lower body biomechanics of 37 recreational runners (19 f, 18 m) were analysed for eight footwear and two running speed conditions. Presenting the effect size Cliff’s Delta enabled the interpretation of gender differences across a variety of variables and conditions. Known gender differences such as a larger range of hip movement in female runners were confirmed. Further previously undiscovered gender differences in running biomechanics were identified. In women, the knee extensors are less involved in joint work. Instead, compared to men, the supinators contribute more to deceleration and the hip abductors to acceleration. In addition to differences in extent, women also show a temporal delay within certain variables. For the foot, ankle and shank, as well as for the distribution of joint work, gender differences were found to be dependent on footwear condition, while sagittal pelvis and non-sagittal hip and thigh kinematics are rather consistent. On average, smaller gender differences were found for an individual compared to a uniform running speed. Future studies on gender differences should consider the influence of footwear and running speed and should provide an accurate description of the footwear condition used. The findings of this study could be used for the development of gender-specific running shoes and sports and medical products and provide a foundation for the application of smart wearable devices in gender-specific training and rehabilitation. Full article

Carbon plate running shoes (CPRSs) have gained widespread popularity among elite and amateur runners, representing one of the most substantial changes in running gear over the past decade. Compared to elite runners, however, amateurs run at lower speeds and show more diverse running styles. This is a meaningful difference as many previous studies on CPRSs focus either on highly trained male runners and higher speeds or only on a single CPRSs manufacturer. The present study aims at bridging this gap by investigating how CPRSs from four different manufacturers affect running economy in amateurs of both sexes at their individual running speeds. For this purpose, 21 trained amateur triathletes (12 men; 9 women) completed an incremental treadmill test until volitional exhaustion, yielding running speeds at ventilatory thresholds 1 (v_VT1) and 2 (v_VT2). In a second session, subjects ran five trials of 3 × 3 min (speeds of 90% v_VT1, ½ (v_VT1 + v_VT2), and 100% v_VT2), wearing one out of four different pairs of CPRSs or their own preferred non-CPRS shoes in each trial. Our results show that tested CPRS models resulted in a significant reduction in the mean energy cost of transport, compared to the non-CPRS control condition, with Cohen’s d amounting to −1.52 (p = 0.016), 2.31 (p < 0.001), 2.57 (p < 0.001), and 2.80 (p < 0.001), respectively, although effect sizes varied substantially between subjects and running speeds. In conclusion, this study provides evidence that amateur athletes may benefit from various manufacturers’ CPRS models at their typical running speeds to a similar degree as highly trained runners. It is recommended that amateur athletes evaluate a range of CPRSs and select the shoe that elicits the least subjective sensation of fatigue over a testing distance of at least 400–1000 m. Full article