The record history of running, swimming and ice-skating, over various distances, was analyzed. A mean period of about 66 years for the 18 male events and of about 50 years for the 14 female events was studied. Over a given distance the velocity (v) was related to the dates of the records minus 1900 (T) according to polynomial functions like: v = a0 + a1T + a2T2 + ..... + anTn. In 21 out of the 32 events equations of first or second degree fitted the experimental data. The mean correlation coefficient was 0.979 +/- 0.019 (+/- S.D.). The ratio between predicted (vlp) and actual value (vl) of the last records was 0.999 +/- 0.010. For T corresponding to v1 (Tl), the rate of record growth was slowing down in 5 events. Hence up to June 1981 a tendency towards an asymptotic v was not yet a general phenomenon. At Tl the range of the relative rate of increase of v (dvp/dT . vlp) was 0.9 . 10(-3) per year (800 m - female running) and 12.4 . 10(-3) per year (800 m - female swimming). dv/dT . vlp in swimming and skating was similar in both sexes but 4 times faster than in male running. Less marked differences were found for female running. A lowering of the cost of transport was probably the main reason of the fast growth of swimming and skating records. The numerical constants calculated from linear regression of v versus the time of the races over different distances did not seem to have a clear physiological meaning, as reported in the previous literature.