The evolution of long distance running and swimming

Abstract

ABSTRACTThe modern evolution of long distance running and swimming is documented statistically: body mass (M), height (H), slenderness (S), and winning speed (V). In long distance running (10,000 m), M, H, V, and S are decreasing: these trends contradict the trends in short distance running (100 m). In long distance swimming (1,500 m freestyle), the trends are similar to short distance (100 m freestyle): H and V are increasing. The parallel trends in long versus short distance swimming, and confl icting trends in long versus short distance running are due to dehydration, which is limiting only in long distance running. The speed records ratio running/swimming for long distance sports is decreasing at the same rate as for short distance sports. Running and swimming are subject to speed ‘ceilings’ (V max ) dictated by physics: the current record speeds in running and swimming are close to max 1V.2 1 INTRODUCTIONAnimal locomotion in water, air, and on land is united by body-size scaling rules that are as universal as all the other scaling rules of animal design (e.g., metabolism, respiration, organ sizes). These phenomena of scaling have stimulated an intense activity, which is reviewed regularly, for example, in Refs. [1–5].A recent outgrowth of the progress on animal scaling is the study of sports evolution, particularly, the evolution of speed records in running and swimming [6, 7]. These studies confi rm that what is known about animal scaling can also be used in a predictive sense in the evolution of speed sports. At the same time, speed sports provide a laboratory (a small, carefully defi ned sample) in which to observe the phenomenon of evolution during our life time.The speed sports that have been documented and explained so far in evolutionary design terms are the short distance events, 100 m dash and 100 m freestyle, men and women [6, 7]. In this paper, we extend this study to long distance running and swimming, and unveil a major anomaly: the body sizes and speeds of long distance runners have been decreasing, in contrast with the trends exhibited by short distance runners, and by short and long distance swimmers.2 LONG DISTANCE RUNNINGTo track the evolution of the record breakers in long distance running, we selected the 10 km run, because it is conducted under closely monitored conditions. Unlike the marathon, which is run through the streets of the host city, the 10 km race is held on a track inside the stadium in order to produce results that are much more consistent, as variables such as topography are eliminated. The records and body measurements of the winners are compiled in Table 1. Several graphs are supported by this data, and they reveal clear evolutionary trends. The speed records are shown in Fig. 1a. The body mass (Fig. 1b) exhibited a downward trend during the past 80 years. Combining Figs 1a and b by eliminating the time as a variable we obtained Fig. 1c, which shows that higher speeds correlate with smaller bodies V 24.8M≅