Muscle: Pectoralis
Step 1: Place your hands on a bench and get into a standard pushup position.
Step 2: Lower your body until your chest nearly touches the bench, pause, then push yourself back to the starting position. Maintaining roper form throughout by preventing your Hips from Sagging at any point, keep your core stiff by bracing your abdominal muscles and straighten your legs while your weight on your toes. Repeat.