Abstract
The purpose of this study is to investigate trends over time in critical speed, anaerobic distance capacity and maximal ‘instantaneous’ speed of male and female running record holders. At ten year intervals, a model of human bioenergetics is fitted to the then existing records at nine distances from 100m to the marathon, to provide estimates of these performance attributes. An indicator variable accounts for gender differences. Critical speed for men over the last 100 years and for women over the last 50 years has risen; men by 30% and women by 73% (though still below that of men). Maximal instantaneous speed has risen similarly. Conversely, anaerobic distance capacity has been declining. For men the decline has been slow but significant, but in women it has been dramatic. Application of this model to the progression of running records confirms training and cross-sectional studies suggesting that changes in performance parameters of elite runners are not independent of each other. Evolutionary or training induced performance improvements do not necessarily imply improvements in all parameters of the bioenergetic system.