Based on the Results of Classic Studies Such as Costill

Based on the results of classic studies such as Costill et al. (1971) , which of the following best describes muscle glycogen depletion on successive days of training in well-trained endurance athletes?

A) Because they were well trained, muscle glycogen was only mildly depleted and typically completely restored before the next training session.
B) Muscle glycogen was nearly depleted after the first day, incompletely restored, and subjects were unable to complete training runs on successive days.
C) Males typically deplete and restore muscle glycogen to near maximum levels each day, but females rarely do.
D) Muscle glycogen declined with successive days of training even though a moderate-carbohydrate diet was consumed.