Resisted hip flexion: Stand facing away from a door. Tie a loop in one end of a piece of elastic tubing and put it around the ankle on your injured side. Tie a knot in the other end of the tubing and shut the knot in the door near the floor. Tighten the front of your thigh muscle and bring the leg with the tubing forward, keeping your leg straight. Return to the starting position. Do 2 sets of 15.
Located deep in the front of the hip and connecting the leg, pelvis, and abdomen, the hip flexors— surprise, surprise— flex the hip. But despite being some of the most powerful muscles in our bodies (with a clearly important role), it’s easy to neglect our poor hip flexors— often without even knowing it. It turns out just working at a desk all day (guilty!) can really weaken hip flexors since they tend to shorten up while in a seated position. This tightness disrupts good posture and is a common cause of lower back pain. Weakened hip flexors can also increase the risk of foot, ankle, and knee injuries (especially among runners) Hip muscle weakness and overuse injuries in recreational runners. Niemuth, P.E., Johnson, R.J., Myers, M.J., et al. Rocky Mountain University of Health Professions, Provo, VT. Clinical Journal of Sport Medicine, 2005 Jan; 15 (1): 14-21.. So be sure to get up, stand up every hour or so! And giving the hip flexors some extra attention is not just about injury prevention. Adding power to workouts, working toward greater flexibility, and getting speedier while running is also, as they say, all in the hips The effect of walking speed on muscle function and mechanical energetics. Neptune, R.R., Sasaki, K., and Kautz, S.A. Department of Mechanical Engineering, The University of Texas, Austin, TX. Gait & Posture, 2008 Jul; 28 (1): 135-43..
You can strain or tear one or more of your hip flexors when you make sudden movements such as changing directions while running or kicking. Sports and athletic activities where this is likely to occur include running, football, soccer, martial arts, dancing, and hockey. In everyday life, you can strain a hip flexor when you slip and fall, for example.