Sex-related differences and effects of short and long trail running races on resting muscle-tendon mechanical properties.

The purpose of the study was to assess sex-related differences in resting mechanical properties and adaptations of skeletal muscles and tendons in response to trail running races of different distances using multi-site shear wave elastography assessments of the lower limb, force capacity and blood analyses. Sex differences in resting mechanical properties of knee extensor and plantar flexor muscles and tendons were characterized by shear wave velocity (SWV) measurements in healthy males (N = 42) and females (N = 25) trained in long-distance running. Effects of running distance on muscle and tendon properties were assessed in short (<60 km, N = 23) vs. long (>100 km, N = 26) distance races. Changes in isometric maximal voluntary contraction torque, serum C-reactive protein and creatine kinase activity were also quantified after running races. Higher SWV of relaxed triceps surae muscle was detected in females as compared to males before running races (+4.8%, p = 0.006), but the significant increases in triceps surae muscle group (+7.0%, p = 0.001) and patellar tendon SWV (+15.4%, p = 0.001) after short-distance races were independent of sex. A significant decrease in triceps surae muscle SWV was found after long-distance races in the whole experimental population (-3.1%, p = 0.049). Post-races increase in C-reactive protein and creatine kinase activity were significantly correlated to the relative decreases in triceps surae and quadriceps femoris skeletal muscle SWV (ρ = -0.56, p = 0.001 and ρ = -0.51, p = 0.001, respectively). Resting mechanical properties of muscles and tendons are affected by sex, and adaptations to trail races are related to running distance. Exercise-induced changes in resting skeletal muscle mechanical properties are associated with enhanced indirect markers of inflammation and muscle damage.

Changes in lung function during an extreme mountain ultramarathon.

This study aimed to assess the effects of an extreme mountain ultramarathon (MUM, 330 km, 24,000 D+) on lung function. Twenty-nine experienced male ultramarathon runners performed longitudinally [before (pre), during (mid), and immediately after (post) a MUM] a battery of pulmonary function tests. The tests included measurements of forced vital capacity, forced expiratory volume in 1 s, peak flow, inspiratory capacity, and maximum voluntary ventilation in 12 s (MVV12). A significant reduction in the running speed was observed (-43.0% between pre-mid and mid-post; P < 0.001). Expiratory function declined significantly at mid (P < 0.05) and at post (P < 0.05). A similar trend was observed for inspiratory function (P < 0.05). MVV12 declined at mid (P < 0.05) and further decreased at post (P < 0.05). Furthermore, there are significant negative correlations between performance time and MVV12 pre-race (R = -0.54, P = 0.02) as well as changes in MVV12 between pre- and post-race (R = -0.53, P = 0.009). It is concluded that during an extreme MUM, a continuous decline in pulmonary function was observed, likely attributable to the high levels of ventilation required during this MUM in a harsh mountainous environment.

Training for shorter ultra-trail races results in a higher injury rate, a more diverse injury profile, and more severe injuries: 2022 Mac ultra races.

OBJECTIVES: Determine and compare the epidemiology, clinical characteristics, and injury severity among race entrants training towards different ultra-trail race distances. DESIGN: Retrospective cross-sectional study. SETTING: The six months training period before the 2022 Mac Ultra races (46 km, 80 km, 161 km and 322 km). PARTICIPANTS: Of the 245 race entrants, 162 (66% of Mac ultra-trail runners) consented to analyse their data. OUTCOME MEASURES: Injury rate (injuries per 1000 h of running), point prevalence (% of currently injured participants), injury severity (time loss), and the frequency (n, %) of injuries reported during pre-race medical screening in the six months before the race. Using inferential statistics, we compared the injury rates between the different race distance categories (46 km, 80 km, 161 km, 322 km). All tests were performed at a 5% level of significance. RESULTS: We reported a statistically significantly higher injury rate among 46 km study participants (3.09 injuries per 1000 h) compared to the injury rates reported among 80 km (0.68 injuries per 1000 h; p = 0.001) and 161 km (1.09 injuries per 1000 h; p = 0.028) participants. The lower limb (89%) was the most injured anatomical region, with only 46 km study participants reporting upper limb, trunk, and head injuries (11%). Muscle/tendon was the most reported injured tissue type (56%), with muscle injuries (31%) the most reported pathology type. Shorter distance ultra-trail runners reported the highest injury severity. CONCLUSION: Ultra-trail runners training towards shorter ultra-trail distance races presented with a higher injury rate, more diverse injury profile, and a higher injury severity.

Revealing the true nature of a parachute mitral valve during an ultra-trail race.

Pre-participation screening and management of congenital cardiac valvulopathy in competitive athletes can be challenging, particularly within the context of ultra-endurance disciplines. A 55-year-old female athlete without a reported history of cardiac disease exhibited clinical signs of cardiogenic pulmonary edema during a 156 km ultra-trail race. The echocardiographic assessment revealed the presence of a parachute mitral valve, with no evidence of mitral stenosis or regurgitation at rest, but it demonstrated severe dynamic mitral stenosis during exercise. In competitive athletes, the detection of rare valvulopathy should prompt a comprehensive cardiac evaluation aimed at assessing the potential for dynamic valvular dysfunction.

Mountain Ultra-Marathon (UTMB) Impact on Usual and Emerging Cardiac Biomarkers.

The number of participants in ultra-marathons is increasing. However, the data regarding the impact of this type of exercise on the cardiovascular system are contradictory. In our study, 28 ultra-trail runners were enrolled. Blood samples were collected at three time points: immediately before, immediately after, and 7 days after the ultra-marathon. Different biomarkers were measured. Immediately after the race, the blood concentrations of the different cardiac and inflammatory biomarkers increased significantly. Interestingly, some biomarkers remained high even after 7 days of recovery.

How physical activity and passion color the passage of time: A response with ultra-trail runners.

The aim of this study was to replicate the results of a lengthening effect caused by physical activity already observed in duration length judgment, using the time passage judgment measure, while exploring the effects of passion types (obsessive vs. harmonious) on time perception. A total of 378 ultra-trail runners responded to an online questionnaire in which the type of passion and the passage of time (PoT) judgments associated with both an ultra-trail context and a non-trail daily context were collected. The results showed that participants systematically judged the time as being dilated in a situation of sports practice, thus extending the results obtained in interval duration judgment studies. This study also showed an influence of the type of passion: higher levels of harmonious passion were related to greater feelings of time dilation, while higher levels of obsessive passion were related to greater feelings of both time contraction and time dilation. Results are discussed in light of the two major factors that influence the PoT referenced in the literature, namely, attention and happiness level.

Differential impacts of trail and ultra-trail running on cytokine profiles: An observational study.

BACKGROUND: Endurance running events are known to cause inflammation and result in increased cytokine production. However, the effects of ultramarathons on cytokine profiles are not well characterized. OBJECTIVE: The aim of this study was to describe and compare the effects of a trail (40 km) race and an ultra-trail (171 km) race on leukocyte concentrations and cytokine profiles. METHODS: The study was conducted during the Ultra-Trail du Mont Blanc® ultra-marathon running event, and included 11 runners who completed the 40 km trail run and 12 runners who completed the 171 km ultra-trail. Blood samples were taken before and after the races. RESULTS: Leukocyte concentrations significantly increased after both races. Circulating levels of IL-6, IL-1ß, MCP-1, and IFN-γ were significantly higher after the longer race compared to the shorter race. Furthermore, while both races resulted in significant increases in IL-6 and IL-8, only the longer race resulted in significant increases in MIP-1ß, IL-7, IL-17a, and IL-4. CONCLUSIONS: These results illustrate that a 171 km ultra-trail race results in greater modulations in cytokine profiles than a traditional trail race.

The Energetics during the World's Most Challenging Mountain Ultra-Marathon-A Case Study at the Tor des Geants®.

Purpose: To provide insights into the energy requirements as well as the physiological adaptations of an experienced 50-year-old ultra-marathon male athlete during the world's most challenging mountain ultra-marathon (MUM). Methods: The international race supporting the study was the Tor des Geants®, characterized by 330 km with +24,000 m D+ to be covered within 150 h. Before the MUM, we assessed the peak oxygen uptake ([Formula: see text]) by means of an incremental graded running test. During the MUM we monitored six ascents (once per race day) with a portable gas analyzer, a GPS and a finger pulse oximeter. We then calculated the net metabolic cost per unit of distance (C), the vertical metabolic cost (Cvert) and the mechanical efficiency of locomotion (Effmech) throughout the six uphills monitored. We further monitored the distance covered, speed, altimetry and D+ from the GPS data as well as the pulse oxygen saturation with the finger pulse oximeter. Results: Subject's [Formula: see text] was 48.1 mL·kg-1·min-1. Throughout the six uphills investigated the mean exercise intensity was 57.3 ± 6.0% [Formula: see text] and 68.0 ± 8.7% HRpeak. C, Cvert and Effmech were 11.4 ± 1.9 J·kg-1·m-1, 57.9 ± 15.2 J·kg-1·[Formula: see text], and 17.7 ± 4.8%, respectively. The exercise intensity, as well as C, Cvert, and Effmech did not consistently increase during the MUM. Conclusions: For the first time, we described the feasibility of assessing the energy requirements as well as the physiological adaptations of a MUM in ecologically valid environment settings. The present case study shows that, despite the distance performed during the MUM, our participant did not experience a metabolic fatigue state. This is likely due to improvements in locomotor efficiency as the race progressed.