Changes in Bilateral Hand Force After 30 Minutes of Climbing in Elite Level Rock Climbers

Abstract

Rock climbing is a sport that requires finger flexor strength and endurance to maintain isometric contractions during an ascent. It has been shown that climbers have higher finger flexion strength and endurance than the general population at the proximal interphalangeal joint (PIP). What is unclear, however, is if years of training and conditioning have caused these adaptations to occur bilaterally in both the dominant (D) and non-dominant (ND) arms of elite level rock climbers. It is essential for climbers to have equal, bilateral finger flexor strength and endurance capacity as rock climbing stresses both sides of the body. Weakness on one side may result in a fall or failure to complete a route. PURPOSE: To analyze change in average force production in D and ND finger flexors of elite-level rock climbers over the course of 30 min of climbing. METHODS: 8 elite- level (age: 29.4 ± 4.7 y, climbing experience: 11.1 ± 5.2 y, mean project grade: 9.7 ± 0.3 UIAA) rock climber’s D and ND finger flexor strength was tested using a mounted force transducer. A 20-sec isometric contraction was performed with the arm fixed at 90° elbow flexion and 120° of horizontal shoulder abduction. Subjects were given two warm up contractions on each hand before the 20-sec MVIC. Subjects then climbed on a treadwall for six 5-min intervals. Total climbing time was 30 min. The treadwall rotated at 6 m/min with a 6° overhang. The isometric force assessment was repeated at the end of each interval and kept to less than 3 min to prevent recovery. Force data were analyzed by removing the first and last 10% of the contraction and averaging the remaining 16 sec. Data were expressed both in absolute (N) and as a percentage of the initial MVIC trial (relative). A paired t-test was used to compare the pre-MVIC to the MVIC at 30 min. RESULTS: No statistical differences were found for change in absolute force between D (29.1 ± 26.1 N) and ND (41.5 ± 63.6 N) hands or in relative force between D (8.05 ± 7.5%) and ND (12.09 ± 11.7%) hand. Mean change in force relative to BW after 30 min of climbing: D (0.44 ± 0.39 N/kg BW), ND (0.62 ± 0.96 N/kg BW). CONCLUSION: Elite-level rock climbers do not show a bilateral deficit between their D and ND hands typically seen in other sports. This could be due to years of symmetrical training and the stresses that are applied to both limbs while rock climbing.