Slumping over your keyboard all day can cause the muscles and connective tissue in your upper body to set in that position.

The result: A slightly hunched back, which not only gives you the posture of a caveman, but also puts stress on your lower back, weakens your core, and screws with shoulder mobility when you work out.

This exercise, the kneeling T-spine rotation, helps undo that damage by mobilizing your upper back, says Men’s Health Fitness Director B.J. Gaddour.

Related: Want to Lift More Weight Overhead? Then You Must Do This Move

From a kneeling position, you'll focus on rotating only your thoracic spine, which runs from the bottom of your rib cage to your shoulders.

Since you're performing the movement against resistance, you'll also challenge your core muscles. 

Perform 5 to 10 reps on each side as a warm-up drill, or plug it into a circuit as a core or mobility exercise, Gaddour says.

More Men's Health:
-- 30-Minute Insane Interval Workout
-- Leg Day Workout For Guys Who Hate Leg Day
-- The Hip Stretch That Can Also Build Muscle and Burn Fat
-- The J.J. Watt Workout

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