How to Lose Upper-Body Muscle Mass on a Female

Purposely losing upper-body muscle may seem like a strange idea. Nevertheless, some women who’ve built relatively large arm, shoulder, chest or back muscles may wish to reshape their bodies into a more traditional look. Alternatively, a woman who’s built herself up to play one sport -- throwing the shot put, for example -- may need a slimmer physique to succeed at another activity, such as gymnastics. Whatever your reason, you can remain well-toned while reducing your upper-body muscle mass if you do so carefully.

Reduce the length of your workouts. All else being equal, the harder you work your muscles, the stronger and larger they grow. Women’s muscles won’t bulk up as large as men’s muscles, due to insufficient testosterone levels, but they still respond to exercise, or to a lack of exercise. So if you’re performing two sets of your upper-body exercises, for instance, limit yourself to one set to reduce your muscle mass.

Work out less frequently. For example, perform one upper-body workout each week instead of two or do two instead of three.

Lessen the intensity of your workouts. Reduce the amount of weight you lift or find alternate methods of lowering the intensity. If you do standard pushups, for instance, elevate your hands by 12 to 24 inches to make the exercise easier.

Perform high-rep, low-weight sets of your upper-body exercises. Use very light weights and do 80 to 100 reps to increase your slow-twitch muscle fibers and reduce the larger fast-twitch fibers.

Replace some resistance training with steady-state cardio activities. Ride an exercise bike, use a treadmill or perform a similar aerobic exercise that doesn’t build upper-body strength. If you use an elliptical, don’t pull on the resistance handles.

Wait until at least three hours after your workout to consume protein. The lack of post-workout protein will inhibit your muscle growth.