Lower Limb Power And Reactive Strength In Ultramarathon Running: Comparing Finishers And Non-finishers

Mountainous ultramarathon racing involves high degrees of neuromuscular fatigue and muscular damage. Previous research has identified that greater muscular power or strength differentiates elite ultramarathon performers from road runners; however, the relationship of muscular strength and power to the capability to finish an ultramarathon is unclear. PURPOSE: To describe the muscular strength and power profiles of mountain ultramarathoners and the relationship of these variables to race performance. METHODS: Runners were examined before and immediately after ultra-endurance mountain races of 65, 80, 112, and 193 km. Neuromuscular coordination and muscular power were assessed by five countermovement jumps on a dual-force plate set-up. Jump Height and reactive strength (jump height * time to take-off-1) were recorded as assessments of power and coordination, respectively. Finishers of the race and non-finishers were compared (two-way ANOVA for sex and finish) (Male Finishers = 17, Male Non-Finishers = 8, Female Finishers = 7, Female Non-Finishers = 2). RESULTS: Ultramarathon runners exhibited low jump heights (Male runners = 25.0 ± 5.7 cm, Female = 16.0 ± 4.1 cm), and low reactive strength (Male = 0.25 ± 0.09 AU, Female = 0.17 ± 004 AU) at baseline. There was no difference in jump height (in both sexes) between finishers and non-finishers of an ultra-marathon (Male = 24.6 ± 4.8 vs. 26.0 ± 7.9 cm, Female = 16.8 ± 4.7 vs. 13.2 ± 0.72 cm, respectively). CONCLUSIONS: While ultramarathon runners display low jump heights and low reactive strength, greater muscular power or reactive strength does not appear to affect the capability to complete an ultramarathon. Training for ultramarathons should focus on other determinants of performance, such as aerobic capacity. Natural Sciences and Engineering Research Council of Canada (NSERC-RGPIN-2018-1502)