Midline stabilization is essential for effective functional movement. The midline is the entire spine, and its stability is dependent not just on the core, but also on all the prime movers of the body, including the hip, glutes, and hamstrings. Excessive tightness in any of the prime movers will affect the core muscles, often resulting in low back pain.
Activating our core and glute muscles prior to a lift will make us more aware of our midline and prepare our spine for proper loading. Often when putting weight overhead without an active midline causes an athlete to hyper-extend at the low back, resulting in an unfavorable overhead position. Tightening the core and squeezing the glutes will reposition the athlete from an anterior pelvic tilt to a neutral pelvic position.
The picture on the left shows a good spinal position. The picture on the right shows a poor overhead postition due to an anterior pelvic position and the loss of midline.
Our midline stability improves through practicing functional movements. The front squat and the overhead squat are both exercises that require a lot of core strength, and practicing them will build a great deal of core strength.