While there are more than six muscles used when you perform the bench press or incline bench press, focusing on the major ones can lead to significant improvements in your strength and toning. Some muscles are the agonists, or prime movers, others are antagonists, or those that must stretch to allow the movement to occur, while the small muscles that stabilize the joints during the lift are critical to long-term performance. The same muscles are used in each lift. Consult your physician before beginning any exercise program.
The triceps are the most active muscle in the bench press, and even more active in the incline bench press, largely due to the slightly greater range of motion in the incline bench press. The function of the triceps, which are located on the back of the upper arm, is to extend the elbow, so the greater the rotation and extension at the elbow joint, the greater the activation of the triceps, as they have to work to push the bar to full extension.
Anterior Deltoids and Pectoralis Major
The anterior deltoid is the muscle on the front of the shoulder. It functions to move the upper arm not only up toward your head, but also in to the mid line of your body. It is the second most active muscle in the bench press. The pectoralis major, commonly referred to as "the pecs," functions to adduct the humerus, which means they are responsible for bringing your upper arm into the mid line of your body, and are the third most active muscle in the bench press.
Latissimus Dorsai and Biceps
The latissimus dorsai are the widest muscle of the back, and are commonly referred to as "the lats." These muscles are antagonists, and stretch as the bar descends. These muscles also actively generate a small burst of activity as the bar leaves your chest, which means that training them will not only provide stability in the bench press, but some assistance with the initial drive off of the chest. The biceps function only to stabilize the elbow joint when benching, but stability means safety.
The rotator cuff is actually a group of four muscles that operate to control the inward and outward rotation of the upper arm at the shoulder joint. The supraspinatus and infraspinatus function to rotate the arm inward, and get quite a bit of work in all pressing exercises. The subscapularis and teres minor function to externally rotate the humerus, and get very little work in conventional body building programs. Training these muscles with outward rotations using cables or dumbbells can go a long way to promoting joint health and avoiding injury.
- "Journal of Strength and Conditioning Research" Electromyographic Activity of the Pectoralis Major and Anterior Deltoid Muscles During Three Upper-Body Lifts; Barnett et al.; 2005
- "Journal of Strength & Conditioning Research:" Effects of Variations of the Bench Press Exercise on the EMG Activity of Five Shoulder Muscles; 1995
- "Journal of Physical Anthropology:" Muscle Power Output Properties Using the Stretch-shortening Cycle of the Upper Limb and Their Relationships with a One-Repetition Maximum Bench Press; 2006
- "Strength Training Anatomy - 3rd Edition (Sports Anatomy)"; Frederic Delavier; 2010
- Polka Dot Images/Polka Dot/Getty Images
This article reflects the views of the writer and does not necessarily reflect the views of Jillian Michaels or JillianMichaels.com.