The serratus anterior is a wing-like muscle that wraps around the upper outer portion of the ribcage. It attaches to the shoulder blades, helping to stabilize and control them. It also helps people punch, push, press, and round the shoulders forward. People with a weak serratus anterior often have winged shoulder blades.
A great exercise to help strengthen the serratus anterior muscle is protraction and retraction in a plank position.
Begin in a plank position, lining up your elbows under your shoulders. Keep your face parallel to the floor, your upper back broad and flat, your waist long, and your navel drawn in toward your spine. Keep your gluteus engaged and your legs long and straight. Reach out through your heels as you hold this position.
With a steady breath lower your chest toward the floor by retracting your shoulder blades. Exhale as you push the floor away from yourself, rounding your shoulders.
Keep your focus on your serratus anterior muscle and your internal or lower abdominal muscles.
Many people cheat through this exercise by using their chest muscles or upper abdominal muscles. To really get the benefit of this exercise, you must calm your mind and focus on proper alignment. To do that, it is necessary to relax the muscles you do not want to use and find the muscles you do want to move from. If you cannot do that, try again on another day or build up to this exercise.
If you are not used to actively relaxing isolated areas of tension and engaging other areas, you may want to begin exploring more mind-body modalities such as the Gyrotonic Expansion System or Pilates.
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