Starting Position: Come to a hands and knees position (quadruped) on the mat with your hands directly under your shoulders; fingers facing forward, or slightly inward and knees under your hips. ?Engage the abdominals and pull the shoulder blades down your back.
Reach one leg out and away followed by the other leg, bringing you to plank position. Keep the abdominals/core engaged to brace the torso. Your head should be aligned with your spine. Your feet are together with your toes tucked under and your heels reaching toward the wall behind you.
Downward Phase: Slowly bend the elbows, lowering your body toward the floor. Keep the torso rigid and the head aligned with your spine. Do not allow your low back or ribcage to sag or your hips to hike upward. Engage your butt (glutes) and thigh (quadriceps) muscles to help maintain stability and a rigid body. Try to lower yourself until your chest or chin touch the mat or floor. Your elbows should stay close to the sides of your body or be allowed to flare outwards slightly.
Upward Phase: Press upward through your arms, straightening the elbows. Keep the torso rigid and head aligned with your spine. Imagine pushing the floor away from you. Do not allow your low back to sag or your hips to hike upward.
An alternative position is to keep your fingers facing forward and your elbows close to your sides during the downward phase. This shifts the emphasis from the chest muscles onto the triceps and may reduce stresses in the shoulder joint.
Pushing through the outside surface and heel of your palm provides greater force in your press and stability to your shoulders.