One pattern we see fairly often is people developing low back pain when they combine strength training with running.
This is especially common in people doing CrossFit or other high intensity training programs where running is mixed with movements like squats, deadlifts, overhead presses, or Olympic lifts.
There are several reasons this can happen, so let's talk through a few of the most common ones.
1. Tight Hip Flexors
One of the first things I look at is hip flexor mobility. If your hip flexors are tight, they can pull the pelvis into an anterior tilt, which increases stress on the lumbar spine. They can also limit your ability to fully extend your hip while running.
When your hips cannot move the way they are supposed to, your low back often has to make up the difference. Now imagine combining that with heavy back squats, deadlifts, or overhead presses. The cumulative stress on the low back can become more than your body is prepared to handle, resulting in pain or stiffness after your workout.
2. Weak Lumbar Extensors
Another common contributor is weakness in the muscles that support the spine. The lumbar paraspinals and multifidus help stabilize the spine and absorb the repetitive impact of running. When these muscles are weak, the spine takes on more stress than it can handle.
3. Poor Core Control
Your core muscles help transfer force between your upper and lower body during running. If your core is not doing its job, the low back has to compensate, leading to pain over time.
The good news is that all of these issues can be addressed with targeted mobility work, strengthening exercises, and proper programming. If you're dealing with low back pain when running, I'd love to help you figure out the root cause.
— Dr. Caleb