The average male–female performance difference in the three sports of track athletics, swimming and time trial cycling are examined between the years 1948 and 1976. During this period females have gradually come to participate in a much larger number of events, particularly those of longer duration. In each of these three sports, women's performances in relation to men's have more or less continuously improved and it appears that if the changes between 1948 and 1976 are maintained, average female performance will equal that of males for all events currently competed in by both sexes in these sports at some time during the next century. Estimates as to when, precisely, this will occur vary somewhat according to the basis on which the calculations are made. The other main change evident during these years is that in all three sports women's performances relative to men's for events of long duration have become as good or better than their relative performance at events of short duration.