Which of the following exercises would promote the highest increase in serum testosterone concentrations?
A . 1 set of deadlifts at 60% of one-repetition maximum
B . 3 sets of deadlifts at 90% of one-repetition maximum
C . 1 set of barbell curls at 60% of one-repetition maximum
D . 3 sets of barbell curls at 90% of one-repetition maximum
Answer: B