Climbing-specific finger flexor performance and forearm muscle oxygenation in elite male and female sport climbers

Climbing performance relies to a great extent on the performance of the finger flexor muscles. Only a few studies investigated this performance in top class climbers and only one study compared gender-specific differences. This study investigated the climbing-specific finger flexor strength and endurance and related muscular oxygenation in 12 elite female and male climbers and 12 non-climbers. After the assessment of maximum voluntary finger flexor contraction (MVC), two isometric finger flexor endurance tests were performed at 40% MVC until exhaustion. A continuous isometric test was followed by an intermittent isometric test (10 s contraction, 3 s rest). Changes in oxygenation of finger flexor muscles were recorded using near infrared spectroscopy. MVC and strength-to-weight ratio were greater in climbers than non-climbers (P = 0.003; P < 0.001) and greater in men than women (P < 0.001; P = 0.002). Time to task failure for the intermittent test and the force-time integrals for the continuous and the intermittent test were also significantly greater in climbers (P = 0.030; P = 0.027; P = 0.005). During the intermittent test, re-oxygenation of the working muscles was faster in climbers (P < 0.05) without gender-specific differences. Close correlations were demonstrated between the best on-sight climbing performance and strength-to-weight ratio (r ² = 0.946, P < 0.001) only in female climbers. The superior intermittent finger flexor endurance of climbers over non-climbers may be explained by the faster re-oxygenation of the finger flexor muscles during the short rest phases.