Running injuries occur in about 37%-56% of average recreational runners annually, with up to three-quarters of those injuries occurring due to overuse*. Often, runners will turn to the shoe to correct a problem or nagging pain with running, but the biomechanical truth is that the shoe may be only a small piece to a very large and complex puzzle.
Running is a closed-chain kinetic exercise which involves compressive forces and the utilization of multiple joints and muscle groups simultaneously. The running stride produces repetitive, compressive translational forces from the end of the toe to the top of the skull – this involves over 150 joints forming the “kinetic chain”. Presence of skeletal, connective tissue, or muscular dysfunction – a “kink” in the chain – can occur in the form of weakness, tightness, poor alignment, and a host of other problems in the intricate anatomy.
So how can you know where the problem is coming from if you have a nagging injury? The first thing to consider is if you have had a recent change in one of the “S-Factors”: Shoe, Speed, Schedule, Stride (heel strike, midfoot, etc), or Surface (concrete, gravel, trail, etc). If your injury started or has worsened since a change in one of these variables, this could be the likely culprit. The body will react to overuse or change which it is unprepared for with pain and/or compensation. If you can identify and correct this variable and the injury keeps nagging, you may have some other dysfunction somewhere along the kinetic chain.
A friend of mine, who is fairly new to running, has always combated a bunion on her right foot. She thought a wide toe box in her shoe would do the trick – unfortunately it didn’t. The benefit of having a physical therapist as a friend is that you can squeeze out free advice about your injuries – so I recently took a quick look at her from head to toe. I found that she had a weak medial quadriceps muscle on the right leg, poor pelvic alignment, plus tight glutes and hip rotators on both legs. “How could that be what makes my toe hurt worse??” I gave her a few stretches and exercises to address the issues, and three weeks later she texted me with the good news of a pain-free run.
It is important to consider the entire body (core, hips, knees, etc) when training for running. A consistent regimen of stretching, strengthening, and cross-training is important to keep the body happy and balanced. If an injury or irritation doesn’t resolve with rest or is getting worse, the smart plan to keep your training going is to address the problem early with the help of a medical professional such as a physical therapist, and avoid playing catch up on miles.
* Sports Med. 1992 Nov;14(5):320-35. van Mechelen W.