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Purpose: To characterize the acute effects of a long-duration adventure race on knee extensor (KE) fatigue and the knee functional ratio in adolescent athletes. Methods: Twenty trained male adolescents (aged 14–17 y) performed an adventure race of 68.5 km. Maximal voluntary isometric contraction (MVIC) KE and knee flexor torques were measured before and immediately after the race. Central and peripheral components of neuromuscular fatigue were quantified from the maximal voluntary activation level and the doublet peak torque (Tw100), respectively. The peak eccentric knee flexor torque to concentric KE torque ratio was also measured to determine functional ratio. Results: The race completion time was 05:38 (00:20) hours. Significant reductions in MVICKE (−14.7%, P KF (−17.0%, P P 100 remained unchanged. Peak eccentric knee flexor torque decreased 16.0% (P P Conclusion: The adventure race induced a moderate fatigue, which was mainly explained by central factors without significant peripheral fatigue. However, particular attention should be paid to the knee muscular imbalance incurred by the race, which could increase the risk of ligament injury in adolescent athletes.

International audience; PURPOSE: This study aimed at assessing the prevalence of adverse cardiac events, as identified in the media, in world-class athletes according to their sex and sports discipline. METHODS: All female and male’ athletes, from 30 individual Olympic sports, ranked in the international yearly top 10 between 2006-2018, were included. The name of each of them was associated in a Google search with selected key terms related to heart disease and/or acute cardiac events after their inclusion date. Global and sex-specific adverse cardiac event hazard function λ were calculated for each sport. Global and sex-specific prevalence of cardiac events were calculated, then compared (Fisher’s exact test) between all sports. RESULTS: From the 2471 athletes included, 15 cases of cardiac events (prevalence 0.61%) were reported; 2 sudden cardiac deaths (0.08%) occurred in male athletes. The other events were related to arrhythmic events (n = 13), mainly supra-ventricular arrhythmias (n = 9). All surviving athletes were able to continue their career, mostly after ablation procedure. Male endurance athletes accounted for 7 events among which 3 events occurred among short-distance triathletes. Events among women were comparatively rare (n = 4), and all were observed among short-distance triathletes. CONCLUSIONS: A relatively unexpected high prevalence of cardiac events in endurance elite athletes, was observed as compared to other sports, mainly in short-distance male and female triathletes. This raises the question of particular cardiovascular constraints in this discipline, and underlines the urge of international longitudinal follow-up studies in these kinds of athletes.

We investigated the acute cardiac consequences of a long-duration (5 h) adventure race in adolescent athletes from evaluations of left ventricular (LV) strains and myocardial work. Twenty trained male adolescents (i.e. 8 ± 4 h·week

International audience; iNTroducTioN: little is known about the biochemical consequences of endurance activities in adolescents. The present study aimed to examine the impact of a long-duration adventure race (>5 h) on hydration status, blood electrolytes and biomarkers of kidney function in adolescent athletes. MeThodS: Twenty male adolescents aged 14 to 17 y (mean±Sd; body mass: 59.7±9.1 kg and maximal o 2 uptake: 56.2±4.6 mL•kg-1 •min-1) volunteered to participate in a competitive adventure race of 68.5 km. Volunteers could drink ad libitum and fluid intake was monitored throughout the race. Blood samples were collected before, within 15 minutes after, and 24 hours after the race to monitor blood electrolytes (sodium, potassium, chloride), creatinine and blood urea nitrogen (BUN). Body mass and urine specific gravity (USG) were also measured across the same time points. reSulTS: The race was completed on average in 05:38±00:20 h:min under cold and rainy conditions (10-15 °c and 83-93% of relative humidity). fluid intake was 1.45±0.66 l and body mass decreased by 1.2% compared to before the race (p

The present study investigated the acute effects of a mixed-modality, long-duration adventure race on pulmonary function in adolescent athletes. Twenty male adolescents aged 14 to 17 years volunteered to participate in a wilderness adventure race of 68.5-km. Expiratory function was evaluated before, immediately after, and 24 h after race completion. Measurements included forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1) and peak expiratory flow (PEF). Maximal inspiratory and expiratory mouth static pressures (MIP and MEP, respectively) were also measured using a portable hand-held mouth pressure meter across the same time points. The mean completion time of the race was 05:38±00:20 hours. A significant post-race decrease in FVC was observed immediately after the race (−5.2%, p=0.01). However, no significant changes were observed for FEV1, PEF and the FEV1/FVC and FEV1/PEF ratios. In addition, estimates of respiratory muscle strength (MIP and MEP) were unaffected by the race. The long-duration adventure race induced no marked reduction in expiratory pulmonary function and this response was associated with no apparent respiratory muscle fatigue. Therefore, the pulmonary system of trained adolescent athletes was sufficiently robust to sustain the mixed-modality, long-duration adventure race of ~ 5–6 h.

International audience; Objectives: To assess cardiac and vascular adaptations in long-distance male triathletes and the influence of an increased training volume on these parameters. Design: Case-control study using long-distance male triathletes (Tri) (n = 12) and an age-matched cohort of sedentary volunteers (Ctrl). Methods: All participants gave an informed consent and underwent a Cardiovascular Magnetic Resonance imaging (CMR) exam to measure left and right ventricle functional parameters, and aortic parameters (surface, strain, compliance, pulse wave velocity). This exam was repeated in the triathletes' group after an increased training volume of at least 2 h/week for six weeks. Results: Compared to control volunteers, triathletes presented at baseline a typical pattern of athlete's heart (higher end-diastolic, end-systolic and stroke volumes index, p ≤ 0.009, and lower cardiac rate, p = 0.015) but similar vascular characteristics except a trend towards an enlarged ascending aorta (surface 942 ± 106 vs 812 ± 127 mm 2 , p = 0.058). Between the two visits, the triathletes increased their weekly training time from 9.67 ± 2.43 (Tri1) to 12.15 ± 3.01 h (Tri2): no modifications were found regarding cardiac parameters, but compliance and distensibility of the ascending aorta increased, from 2.60 to 3.34 mm 2 /mmHg (p = 0.028) and from 3.36 to 4.40 × 10 −3 mmHg −1 (p = 0.048) respectively. Conclusions: Using CMR, we showed that vascular characteristics of the ascending aorta may vary along the sport season in endurance athletes. This remodelling could be considered as a physiological adaptation, but could eventually lead to an adverse vascular remodelling.