Sitting for extended periods causes the muscles at the front of your hips—your hip flexors—to become tight and shortened. At the same time, the glutes in the back grow weak and overstretched. This imbalance tips your pelvis forward into what’s called an anterior pelvic tilt, throwing off your posture and alignment from the ground up. One powerful way to help reverse this is with the Air Bench exercise. Find a sturdy wall and wear shoes so your feet don’t slip. Walk your feet forward until your k