Grimston, S. K., & Hay, J. G. (1986). Relationships among anthropometric and stroking characteristics of college swimmers. Medicine and Science in Sports and Exercise, 18, 60-68.

Frontal areas, cross-sectional areas, and lengths of body segments were measured on 12 members of the University of Iowa men's swimming team during the Big Ten Championships over two years. Data were gathered through photographic procedures. Stroke length, stroke frequency, and swimming speed were determined from five films of competitive events for each subject. Anthropometric variables were correlated with three swimming performance variables.

Six measures of anthropometry, five of them determined genetically, were significantly related to one or more swimming performance variables.

1. Stroke length was correlated positively with axilla cross-sectional area (.74), arm length (.68), hand cross-sectional area (.57), leg frontal area (.61), and foot cross-sectional area (.68).
2. Stroke frequency was correlated negatively with axilla cross-sectional area XSA (-.73), arm length (-.59), leg length (-.64).
3. Swimming speed was not correlated with any of the variables.

Anthropometric variables accounted for 89% of stroke length, 41% of stroke frequency, and 17% of speed variances. The axilla cross-sectional area was shown to have the largest relationship accounting for 54% of the variance in stroke length and 24% in stroke frequency. The body structure or structural part of a male swimmer was not related to swimming velocity.

It was concluded that speed was influenced little by the physique of a swimmer but that stroke length and frequency were. It would seem that bigger swimmers stroke longer at lower rates while smaller swimmers stroke shorter but rate higher however, despite those assumptions physique types or features are not related to swimming velocity.

Implications. Despite physical chaacteristics of male swimmers not being related to swimming speed, it is often opined that successful male swimmers have been shown to have large feet and hands, and long arms and legs. Inclusion of those variables in studies similar to this one might yield evidence that will clarify that assertion.

[Editor's note: The muscles used during the propulsive phase of swimming include the shoulder extension muscles (sternocostal part of the pectoralis major, latissimus dorsi, and teres major). These are all situated in the axilla region and lead to the suggestion that muscle size in this area which adds to the cross-sectional dimension contributes to the propulsive force involved in swimming. This is a variable that can be influenced by training and should be considered for programming and verified by research.]

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