A tight end for the Oakland Raiders chose to do workouts that were 6 sets of 225 lb bench presses. He started at a baseline of 51 reps.
After 3 weeks with cooling between sets, his reps increased to 60 (improvement of 17.6%).
During a 4-week control period with no cooling, he maintained his gains but did not improve further. Then during another 2-week period using cooling between set, his reps increased to 67 per session (a total improvement of 31.4%).