Bodybuilding workouts typically include resistance and cardio training designed to increase muscle mass and decrease body fat for a more muscular appearance and improved health. Resistance training with weights, body weight and gravity, places an overload on specific muscle groups, resulting in increased muscle fiber strength and size. When combined with decreases in body fat, muscular definition improves. Bodybuilding workouts are often grouped according to the muscle group that is targeted. Larger muscles are assisted by smaller muscles with each exercise.
Chest, Shoulder and Triceps
Your chest, shoulder and tricep muscles are your push muscles. They work together, exerting force to push resistance away from your body. Your chest, the pectoralis group, and shoulders, the deltoid group, are larger muscles that are assisted by your triceps, located in the back of your upper arm. Chest press and shoulder press exercises, performed with dumbbells or barbells, are compound exercises, involving movement from your shoulder and elbow joints. For both exercises, your chest and shoulders work to move your shoulder joint, while your triceps contract to move your elbow.
Back and Biceps
Your back and bicep muscles are your pull muscles. They work together, exerting force to pull resistance toward your body. Your back, consisting of your latissimus dorsi and rhomboid muscles, are larger muscles assisted by your biceps, located in the front of your upper arm. Pulldown and rowing exercises, performed with cable pulleys, barbells or dumbbells, are compound movements involving movement from your shoulder and elbow joints. Your back works to move your shoulders, while your biceps contract to move your elbow.
Your core muscles -- your abdominal, lower back and hip muscles -- work to stabilize and mobilize your spine and hips. Your abdominal muscles and hip flexors contract to flex, or bend your torso forward. Your lower back muscles contract to extend or bend your body back. Your obliques, or side abdominal muscles, work to rotate or laterally bend your torso. These muscles are involved in all exercises, working to move your torso or keep your torso stationary while you move your limbs. Improving core strength helps to improve posture and alignment while reducing the risk of injury.
Hamstrings, Glutes and Calves
Your hamstrings, glutes and calves, located in the back of your legs, work together to move your hip and knee joints. Your hamstrings consist of your biceps femoris, semitendinosus and semimembranosus muscles. They work to flex or bend your knee joint. They are assisted by your gluteal group, or buttocks, and your gastrocnemius, or calf muscle. Together, they also extend your hip and help you stand. Your calves work alone to point your toe and lift your heels up. While running or walking, they work after you extend your leg to bring your leg back toward your body.