Biochemical evaluation of running workouts used in training for the 400-m sprint.

A 400-m runner relies primarily on the lactate system for energy production. Although several running distances and schemes are used in training for this event, it is not clear which one(s) causes maximal activation of the lactate system so as to optimize adaptations of the lactic capacity. This study examined the effect of 4 running workouts differing in distance (300 vs.