Man in green tank top and blue shorts performing low lunge hip flexor stretch Why the tightest, most skeptical men who try this routine never go back — and what that says about the future of male fitness. Man in green tank top and blue shorts performing low lunge hip flexor stretch There's a moment most men know well — that sharp protest your lower back makes when you stand up from your desk, or the locked-up hips screaming after a long drive. You stretch a little, shake it o