Context Dependent Trade-offs In Body Size Within Olympic Sports

Abstract

There are context dependent trade-offs in body size observed among elite runners. Elite runners who complete in longer distances exhibit smaller body size (height, mass, and body mass index [BMI]) compared to elite runners who compete in shorter distances. However, it is unclear if this trade-off in metrics of body size is observed in elite freestyle swimming or cycling. PURPOSE: To compare metrics of body size between shorter and longer distance events of male and female athletes who competed in running, swimming, or cycling events in the London 2012 Summer Olympics. METHODS: Using univariate analyses of variance, metrics of body size of male and female athletes were analyzed across event distances within each sport. Data were included for 1,030 runners (518 males; 512 females), 661 swimmers (322 males; 339 females), and 379 cyclists (241 males; 138 females). RESULTS: Males were taller (P < 0.001), heavier (P < 0.001), and had a larger BMI (P < 0.001) across all sports, events and distances compared with females, with no observed sex-related interactions (P > 0.05). Runners competing in longer event distances (1500 m or longer) had smaller body size than runners competing in shorter event distances (800 m or shorter) (height, mass, and BMI, P < 0.001 for all). There was no difference in BMI between swimmers competing in longer (400 m or longer) compared to shorter event distances (200 m or shorter) for males (P = 0.107) or females (P = 0.578). However, shorter distance swimmers were taller than longer distance in both males (188 ± 8 vs. 185 ± 8 cm, P = 0.013) and females (174 ± 7 vs. 172 ± 7 cm, P = 0.014). Athletes competing in longer events (road cycling) had a smaller BMI than shorter distance events (track cycling) for both males (21.7 ± 1.3 vs. 23.9 ± 2.7 kg·m-2, P < 0.001) and females (20.3 ± 1.8 vs. 22.2 ± 2.1 kg·m-2, P < 0.001). These differences in BMI were primarily due to ~10% greater body mass among track cyclists compared to road cyclists for both males and females (both, P < 0.001). In contrast, height was not different between track and road cyclists for males (P = 0.864) or females (P = 0.163). CONCLUSION: These data suggest that there is a trade-off between body size and event distance for Olympic running, swimming, and cycling, such that smaller athletes were observed in longer compared to shorter distance events for both sexes.