Finger Strength Does Not Decrease With Rock Climbing To the Point of Failure

Medicine & Science in Sports & Exercise:
May 2003 - Volume 35 - Issue 5 - p S264

F-12K Free Communication/Poster Athletic Performance

Watts, P B. FACSM; Jensen, R L. FACSM; Moss, D M.; Wagensomer, J A.

Northern Michigan University, Marquette, MI

Experienced rock climbers often identify the hand and fingers as primary
areas of failure in competitive climbing. It has been suggested that the
inability to maintain a specific finger configuration is the causative factor, however, there is a lack of research regarding fatigue of finger flexor muscle in climbing.

PURPOSE
To investigate changes in maximum finger force and forearm electromyogram (EMG) that result from performance of a difficult climbing task to the point of failure.

METHODS
Ten experienced rock climbers (age = 30.1± 13.1 yr) volunteered as subjects. Maximum handgrip strength (MHG) was measured via dynamometer with the best of two trials for the right hand recorded.
Finger force (FF) was measured via a piezoelectric force sensor fitted witha plate to accept the first digits of four fingers. Force was applied to the
plate/sensor by the fingers of the right hand via a 3-second maximal
contraction. Forearm EMG was recorded at 500 Hz from surface
electrodes placed 1/3 of the distance from the medial epicondyle of the
humerus to the styloid process of the radius and a point 2 cm distal. EMG
and force data were acquired simultaneously via a BioPac MP100 system
and microcomputer. The raw EMG was integrated (IEMG) via root mean
squared. Peak FF measurements were recorded in kg immediately before
(pre) and immediately after (post) the subject climbed a repeated series of
movements on 45-degree overhanging terrain until the point of a fall or
inability to progress.

RESULTS
FFpre was significantly less than MHG (22.4±6.5 vs 55.6±8.8 kg),
however FFpre IEMG and MHG IEMG were not significantly different.
Climbers completed a mean of 37±17 hand movements during the climbing task. There were no significant differences between FFpre vs FFpost conditions for peak force or IEMG.

CONCLUSION
The primary cause of failure during climbing on terrain of the nature
employed in this study is not a decrease in the ability to produce concentric finger force.