Take 200 400 mg of caffeine

Research shows that caffeine taken preworkout increases fat burning and endurance and blunts muscle pain during training, which means you can do more reps. A more recent study, from the University of Nebraska Lincoln, indicates that subjects who took a caffeine supplement before their workouts immediately increased their one rep max 1RM on the bench press by about 5 pounds. Studies show caffeine supplements work better than caffeine from coffee.