Thoracic spine mobility is often overlooked and underappreciated. Thoracic rotation is an absolutely necessary movement for all athletes. Think about sports like boxing, hockey, baseball, tennis, and lacrosse where the ability to rotate directly impacts how much force/power is developed. Without the appropriate degree of thoracic rotation, you could potentially cause abnormal stress on other areas of your body. Our bodies are masters of compensation, so we will find a way to get rotation from somewhere, and that's not always from the appropriate spot! Other than rotation, thoracic spine extension also plays a major role in our ability to reach overhead. Think about an overhead serve, or reaching overhead to get a rebound in basketball. Same as a lack of rotation, a lack of extension could set you up for shoulder injury or just overall limit your ability to compete at a high level if you aren't able to get those arms overhead.
Now, sometimes mobility, or lack thereof, is truly the problem. Other times, motor control is more of an issue. Motor control is basically your ability to control movement. It can be hard to decipher the difference, and that's when an evaluation from a movement professional, like a physical therapist, comes into play.
EXERCISES FOR INCREASING THORACIC MOBILITY
Thoracic Extension Self Mobilization with Foam Roller
2. Kneeling Thoracic Extension/Lat Stretch with Stick
3. Sidelying Thoracic Rotation (Open Book)
4. Half Kneeling Thoracic Rotation Against Wall
EXERCISES FOR INCREASING MOTOR CONTROL
Split Stance Thoracic Rotational Row
2. Split Stance Med Ball Rotational Scoop Toss
3. Half Kneeling Medicine Ball Rotational Toss
4. Single Leg Airplane with Band Resistance