Your Hip Flexors are the deep muscles of the body which are responsible for bending at the waist and for raising your leg. The primary ones being the Psoas Major and the Iliacus – or more commonly referred to together as the Iliopsoas muscle.
Unfortunately, most people have poorly conditioned hip flexor muscles, which is why we often find ourselves bending, leaning or lifting with our lower backs. Needless to say, this leads to all sorts of problems, some of which include: poor posture, lower back pain and sometimes even severe disc injury.
Besides working out, sitting down for long periods of time also contributes to tight hip flexors and lower back pain, so if you are stuck at a desk all day, be sure to get up and stretch your legs from time to time, along with this easy lower back stretch, as shown by Dr. Kai Morigawara.