This exercise is designed to improve thoracic or upper back mobility while stretching your chest and upper back muscles.

- Start on all fours, with your hands directly beneath your shoulders and your knees below your hips.

- Lift one hand off the ground, reach under your body as far as possible, and hold for a few seconds. Next, pull your hand back and raise it in the air as you rotate outward toward the ceiling.

- Slowly bring your arm back to the starting position and repeat the movement with the other hand, reaching it under your body to the opposite side.

- If you're unable to get on your hands and knees on the ground, rest your hands on the counter, and step backward into a plank position.

- Reach one arm underneath and across your body, then slowly rotate your trunk to reach your arm up toward the ceiling. Repeat with the opposite arm.

I recommend 8-10 reps on each side. This exercise can be done before, during, and after exercise.