Runners and Lower Back Pain
By Rachael Underwood
Despite plenty of research on the topic, we still can’t isolate exactly what causes pain. What we do know is that the spine, for all its strength and versatility, doesn’t cope well with abnormal or sudden and excessive forces. In running, this can occur with abnormal stride mechanics or strength imbalances.
During the running stride, the lumbar spine must accommodate movements in the pelvis and trunk as well as provide a fairly rigid anchor point for muscles. The abnormal loading of the spine typically comes from one of these two functions.
Excessive forward/backward tilting of the pelvis can occur with stiffer hip joints, longer stride length, tight hamstrings, overactive hip flexors…the list is endless. Excessive sideways tilting of the pelvis can occur with poor hip/foot stability, longer stride length and stiffer hip joints. Each of these causes forces the pelvis to move which then causes excessive movement in the lumbar spine. This effect can be more pronounced and easier to trigger if the spine itself has excessive stiffness. This stiffness may be related to previous back injury, wear-and-tear or a prolonged period of irritation of the area.
Excessive forces due to muscle action can result in lower back pain from direct forces, via the muscle connection pulling on the spinal segments, or indirect forces, by pulling on the pelvis or trunk which in turn applies force to the lower back. Tight or overactive hip flexors can cause trouble during the stride while the leg is behind the centre of body weight. As the leg moves backwards the hip flexors pull directly on the spine, creating a forward shearing force on the vertebrae. Once the leg lifts off the ground, strong forces from overactive hip flexors add to the shearing forces. By comparison, tight/overactive hamstrings exert their pull while the leg is in front of the body, causing a backwards tilt in the pelvis which adds load to the back.
The fix for any back problem needs to address a number of issues: it should ease the pain so you can maintain your running program, albeit with a reduced load initially. Next you’ll need advice on everything from occupational spinal loading (sitting at a computer) to stride mechanics, aimed at decreasing the abnormal load. You’ll also need a comprehensive exercise program to work on strength and muscle patterns.
Easing the pain can be achieved with targeted massage, specific stretches and spinal treatment if needed. You could get advice on occupational loading from almost any physio or chiropractor but the running-specific advice requires a thorough understanding of both the spine and running mechanics. And lastly, the comprehensive exercise program, is probably where we see the largest deviation from standard therapy. While most back rehab programs focus on back strength, the runner’s program should focus on running-specific activities and correcting the underlying muscle issue, whether it relates to hip flexors, hip stabilisers or muscle overactivity. Simply strengthening the back can add to the overall load on the spine during running and actually make the pain worse.