Spine hygiene

Stuart McGill spent thirty years at the University of Waterloo in Canada doing something nobody else was doing: measuring, in a lab, exactly what loads the human spine, what injures it, and what makes it resilient. He became the person the world's best athletes and the world's worst back pain cases both went to see. His findings are blunt and, for most people, a relief.

First: the spine is built to be stiff and strong while the hips move. Most back injuries come from bending the spine under load, repeatedly, which is what people do when they lift with their back, sit slumped for hours, and then do sit-ups to "strengthen the core." McGill's rule is no loaded spine flexion. Hinge at the hips; keep the back neutral.

Second: endurance protects the back better than strength. The muscles around the spine need to hold, for a long time, more than they need to lift heavy. So his prescription, which he calls the Big Three, is three endurance exercises done daily: the modified curl-up, which trains the front without bending the spine; the side plank, for the sides; and the bird dog, for the back. Short holds, ten seconds, several reps, every day. It takes five minutes and it's the best-tested back program in existence.

Third, and this is the one I'd frame: most back pain is not a mystery and not a life sentence. It has a cause, usually a movement the person does all day without knowing, and it has a fix, which is to stop doing the movement and build the endurance.

It belongs in the second month because the brace you learned under the bar on day twenty-four is the same brace McGill teaches for picking up a child. The spine likes one shape. Keep it, and move everything else around it.