A theoretical model was developed to identify anthropometric variables relevant to success in swimming. Frontal areas, cross-sectional areas (XSA), and lengths of body segments were measured oh twelve members of a men's college team using a photographic procedure. Motion-picture films were taken of the subjects competing in freestyle events and were analyzed to determine the average stroke length (S&OV0226;), average stroke frequency (S&OV0460;), and average stroking speed (&OV0408;). Correlation arid multiple regression procedures were used to determine the relationships among the anthropometric variables and S&OV0226;, S&OV0460;, and &OV0408;, respectively. Of the 21 anthropometric variables selected with the aid of the theoretical model, 6 were found to be significantly related to one or more of the measures of swimming performance when the influence of event distance was partialled out (P≤ 0.05). The anthropometric variables characterizing the subjects accounted for 89% (S&OV0226;), 41% (S&OV0460;), and 17% (&OV0408;) of the variances in the measured characteristics of their strokes. The axilla XSA was shown to have the largest influence on both S&OV0226; and S&OV0460;, accounting for 57% of the variance in the S&OV0226; and 24% in the S&OV0460;. These results suggest that although &OV0408; is little influenced by the physique of a swimmer, the combination of S&OV0226; and S&OV0460; used to attain a given &OV0408; is very much a function of his physique.