Even though you might think that running is mostly a cardio workout primarily involving your legs, your lower back plays a central role in this exercise.  It is a part of your core and it assists you by holding your upper body vertically.  As a result, when you’re running, your lower back is required to do this job for an extended period of time and while under the stress of additional movement.

An Ohio State University Wexner Medical Center research team, working with the assistance of the National Institutes of Health (NIH) explained that this helps to explain why runners frequently experience lower back pain while trying to enjoy their favorite exercise. The research team conducted a simulation study to take a closer look at why this specific type of pain occurs while investigating what they can do about it for long-term prevention.

Ajit Chaudhari, Ph.D., OSU associate professor in the Department of Kinesiology and the study’s lead author, designed virtual models based on the bodies of eight real-life runners.  This allowed the researchers to closely examine the way the impact of running on joints and bones.

Following the completion of the simulations, researchers worked to alter some of the muscle groups in each of the simulated runners’ bodies.  In some cases, they weakened the muscles and generated fatigue in order to observe the way the body was required to compensate for it.  What they discovered was that weakness and fatigue in the body’s core raised the load on the spine.  As a result, lower back pain could be the result as the spine is forced to make up for the failure of the core muscles to easily support the body.

When muscles in the body were required to compensate for weaknesses in the core, the vertebrae experience a higher amount of strain in the form of pushing and pulling (shear forces), said Chaudhari.  As a result, the individual vertebrae of the spine moved from side to side or slid past each other, boosting overall spinal stress which can result in lower back pain.

The conclusion was that runners who want to prevent lower back pain while running should focus on strengthening the muscles that support the spine.  This includes the entire core, which doesn’t just consist of abdominals.  The muscles deep in the core and throughout the back must also be a focus.  Once those are strengthened, they can better support the spine without suffering fatigue and, therefore, lead to less pain in the lower back.