Resistance training can make life easier, as well as improve your health. Regular sessions increase your lean-muscle tissue, which raises your metabolism to control body fat; resistance training also increases your strength for performance and daily living. When you lose body fat, it is lost all over your body, not just one place. Gaining muscle is different. If you want to make your upper body bigger, train your upper body, not your legs.
Hypertrophy is the muscular enlargement that results from training, according to the National Strength and Conditioning Association. When you perform resistance exercise, you cause microscopic damage to the muscle fibers. This causes a biological response where your body works to heal and/or replace the fibers. This damage/recovery process can lead to an increase in the cross-sectional area of the existing fibers and/or an increase in the number of muscle fibers. These adaptations are localized and you need to train the muscles that you want to change, such as those in your upper body.
Muscles of the Upper Body
To make your upper body bigger you need to train all of the muscle groups in your upper body. This will help you create an overall larger appearance as well as create muscular balance in appearance and function. Include exercises for your back, chest, shoulders, triceps and biceps. Because many of these muscles cross the shoulder joint, you will use some muscles as the primary mover in an exercise while others assist. For example, when performing a lat pulldown, your biceps engage to bend the elbow and assist the large muscles of your back. Pulldowns are done on a cable apparatus in a seated position with the bar overhead. You hold the bar with a wide grip and draw it down to the top of your chest. Slowly extend your arms back to the starting position for one complete repetition.
For each exercise, perform three to six sets of six to 12 repetitions to encourage muscular growth. Perform multiple exercises per muscle group, up to three or four. Bodybuilders are masters of training for muscular hypertrophy and often train each muscle group only one or two days each week. This is because you are using heavy weight for a lot of sets and reps. Your muscles need time to recover so that they can get bigger, often longer than the 48-hour general recommendation. Train two to three muscle groups at each workout so that you can train hard and then recover.
Getting a bigger upper body will not happen overnight. You need to train consistently and results will vary from person to person. In general, men tend to add muscle more easily than women due to testosterone. But your natural genetics also play a role. If you are naturally slim, adding muscle may be more challenging. Diet also plays a role. Good nutrition is key to growing muscle tissue as well as providing energy and the nutrients to recover after a workout.