Train with weights four times per week. Do two lower body sessions and two upper body sessions. The majority of your training should be based around multijoint free-weight exercises, says strength coach Christian Thibaudeau, author of "The Black Book of Training Secrets." These build the most muscle and are most time efficient. Your leg workouts should include squat, deadlift and lunge variations, along with machine exercises such as leg presses and leg curls. For your upper body, do dumbbell presses, dips, chinups, rows and biceps curls. Perform each exercise for three sets of 10 repetitions.