Also known as a chest fly, a chest butterfly exercise involves extending your arms to your sides and bringing them back to the middle of your chest. You can perform this exercise using dumbbells, resistance bands or a chest fly machine. The chest fly and its variations are staples of many resistance-training routines because they work the chest muscles so effectively.
Tones Pectoralis Muscles
The chest butterfly exercise uses a pushing force to strengthen the chest muscles. The target muscle is the pectoralis major. For men, defined pec muscles add a more balanced and toned appearance to the torso. For women, pec exercises can help to lift the chest. You may experience some next-day soreness in the chest after performing butterfly exercises because large muscle groups, like the pectoralis major, don't have the same endurance as smaller muscle groups.
Tones Synergist Muscles
Additional muscles support your chest wall, including the muscles at the front of your shoulders and your bicep muscles at the front of your arms. The chest fly exercise strengthens these synergist muscles, which can add stability to your chest region. This, in turn, helps prevent shoulder injuries because your muscles will be strong enough to support the shoulder joint.
Variations Stimulate Abdominal Muscles
You can add more challenge to your routine if you perform chest fly exercises while balancing your upper back on a stability ball. In addition to working the pecs and synergist muscles, this variation challenges the front and side aspects of your core muscles. The American Council on Exercise recommends this variation for intermediate exercisers. Keep your back as straight as possible and parallel to the floor to avoid injury and strain while performing the exercise.
Increases Athletic Power
You engage both the chest and shoulder muscles in swinging and hitting a ball, so if you regularly play golf or racquet sports, chest butterfly exercises can enhance the power behind your swing.