What is the recommendation for intensity for muscular strength and endurance?

8–12 reps per set and also perform 2–4 sets of each exercise.

Explanation:

The recommendation for intensity for muscular strength and endurance are different for fresher and experienced lifters. For experienced lifters who want to improve their muscular strength, do 8–12 reps per set and also perform 2–4 sets of each exercise, with a 2- to 3-minute rest between sets. To improve your muscular endurance, do 15–20 repetitions with a 2- to 3 minute rest between every two sets in order to relax the muscles.