Hand shape, the ratio of hand-width relative to hand-length, does not significantly influence maximum isometric grip strength capability among either males or females according to Clerke et al.
Females with average and square shaped hands demonstrated significant inconsistency in generating maximum grip strength during a four week follow-up retest which the authors interpreted as potentially related to dynamometer grip handle design. This opinion suggests tool handle shape influences forces the hand can generate.
Two hundred thirty-two injury-free teenagers (118 males, 114 females, 13 to 17 years old) had the length and width of their dominant hand measured. The subjects were divided into three groups for each gender based on the width/length ratio: relatively long-handed (lowest ratio quartile), relatively square-handed (highest ration quartile), and average handed (50% of hands between these two quartiles).
Subjects were tested with a computer linked handgrip dynamometer. They performed three repetitions on five different handle width positions with a 15-second break between each squeeze. Both hands were tested with the maximum grip strength determined as the highest force reading of the 15 trails. Follow up testing was performed on 149 subjects (74 males, 75 females) one- to four-weeks after the initial evaluation.
In general, there was a statistically insignificant diminished strength from long through average to square hands. Seventy-five percent of the subjects had their best strength reading with the handle width in position two. Dominant hands were stronger with a mean difference of 2.53 kg force compared to non-dominant hands.
Except for average and square handed females, follow-up testing provided consistent readings with initial maximum strength findings.
A M Clerke, J P Clerke, and R D Adams.
This article originally appeared in The Ergonomics Report™ on 2005-03-15.