The pectoralis major isn’t just responsible for flexing and adducting the humerus—it also plays a key role in medial rotation of the arm, like during an arm wrestle. Dr. John Basmajian highlighted this in Muscles Alive, noting the muscle’s strong activation during resisted internal rotation.

Try this cable crossover variation to maximize pec contraction:

• Use two independent rope attachments instead of D-handles on a cable crossover unit.
• Grip the ropes supinated (palms facing forward).
• As you bring your hands together, rotate from a thumbs-up to a thumbs-down position.

Keep the weight moderate, focus on the contraction, and feel the difference!