The pushup is a fundamental bodyweight exercise used to build strength in the upper body. The incline pushup is a common modification, performed with the hands elevated on a surface. Understanding which parts of the chest are targeted requires examining the chest’s anatomy and the biomechanics of pressing movements.
Anatomy and Angle Principles
The large, fan-shaped muscle spanning the chest is the Pectoralis Major. It is divided into two main sections: the clavicular head (upper chest) and the sternal head. The clavicular head originates near the collarbone. The sternal head, which originates from the sternum and rib cartilages, constitutes the middle and lower portions of the muscle.
The angle of the torso dictates the emphasis placed on the different heads during pressing movements. When the torso is angled upward, the upper (clavicular) head is emphasized. Angling the torso downward shifts the focus to the lower (sternal) head. This principle is applied across all pressing exercises, including those performed on a flat, incline, or decline bench.
Muscle Activation in the Incline Pushup
The incline pushup is defined by having the hands elevated above the feet, placing the body at an upward angle. This position significantly reduces the percentage of total body weight pressed, making the exercise easier than a standard floor pushup. It is often recommended for beginners or for high-repetition finishing sets.
The upward angle of the torso changes the line of force, mimicking an incline bench press. This shift means the incline pushup primarily increases the activation of the upper chest (clavicular head) and the anterior deltoids (front shoulder muscles). The fibers of the upper chest are positioned to work most effectively when the force is directed upward and slightly inward.
The incline pushup is not an effective way to target the lower pectorals. Research on bench press angles shows that a positive incline angle decreases the activation of the lower sternal head fibers. While the lower chest is still involved, the incline pushup is designed to reduce the workload on the lower chest while increasing the involvement of the upper chest and shoulders.
Targeting the Lower Pectorals
To effectively target the lower portion of the sternal head, the body’s angle must be reversed. Exercises that place the feet higher than the hands, creating a downward body angle, direct the load toward the lower chest fibers. The decline pushup is the most direct bodyweight alternative, as elevating the feet maximizes the tension on the lower pecs.
Another effective bodyweight exercise is the dip, which is a vertical pressing movement. When performed on parallel bars, the dip requires a slight forward lean of the torso to maximize the contraction of the lower sternal fibers. In a gym setting, the decline bench press or a high-to-low cable crossover are excellent alternatives. The decline bench press places the body at an angle that directly recruits the lower chest fibers, while the high-to-low cable crossover isolates the lower chest by pulling the arms downward and across the body.