Is Running Putting Your Lower Back at Risk? The Research on Lumbar Pain Risk Factors

Back pain is very common with as many as 70 percent of the general population experiencing a bout at least once in their life.

But what about back pain in runners? Does running put any increased stress on your back, and if so, does it leave you at a greater risk for injury? What causes back problems in runners?

That’s where we’ll turn our attention in this article.

The research behind lower back pain in runners

The first study we’ll look at, published in 1990 by Garbutt and coworkers at Sunderland Polytechnic in England, used a very creative way to measure stress on the back while running.

Surmising that the impacts absorbed by the back during running affect the overall length of the spine (probably by compressing the discs between the vertebrae), Garbutt, et al., set out to measure the height of a group of marathon runners—some of whom had a history of lower back pain—before and after a series of 30-minute runs at 70, 85, and 100 percent of a marathon pace.¹

Surprisingly, the study found a significant correlation between spinal shrinkage, running speed, and distance covered.  The longer and faster you run, the shorter you get (temporarily of course)!

The amount of shrinkage was small but notable; the heights of the runners dropped by more than a quarter of an inch after a 30-minute run at marathon pace.

But, more importantly, the authors showed that the degree of spinal shrinkage was not related to whether the runner in question had a history of lower back pain.  This provides some evidence that the spine is well-equipped to handle the loads involved with running, even at fast speeds.

Elite athletes and lower back pain

A more direct examination for the relationship between running and lower back pain was published by T. Videman, et al., in 1995.²  Looking at a questionnaires from almost 1,000 former elite athletes in a variety of sports and 620 control subjects, the authors examined the rates of back pain by sport.

In a smaller sample, the researchers examined MRI scans of the lower back of about two dozen runners, weight lifters, shooters, and soccer players.  Among athletes, lower back pain was significantly less common than in the general population.

Additionally, in the MRI studies, weight lifters and soccer players were found to have an increased rate of degeneration and disc bulging in their lower back, while runners and shooters were not significantly different than the general population.

While the runners appeared to have healthier backs than the sedentary controls and the weight-lifting athletes, the authors found no benefit (or drawback) to heavier training loads in the runners when it came to avoiding back pain.

But what about the runners that do get back pain?

Hip flexor tightness and lower back pain

An older study which investigated possible causes for back problems in runners was published in 1985 by Delanie Bach and colleagues at Stanford University.³ A group of runners had their hip flexibility evaluated and compared to that of a control group of sedentary subjects.  The runners had significantly limited ability to flex their hip with their knee straight, indicating that they had notably tighter hamstring muscles compared with the control group.

While there was no significant difference between the runners and control groups when it came to hip extension, the authors deemed both groups to have excessive tightness owing to the fact that many of the subjects sat for 50 percent or more of the day.

They surmised that hip flexor tightness could influence back pain by tugging the pelvis into a more forwardly-rotated position.

However, the authors did not find any relationship between muscle tightness and back pain in the group of runners, perhaps because only ten of the subjects had back pain—not enough to establish statistical significance.

In summary

So, the good news is that the back seems well-adapted to handling the stresses associated with running, seeing as there is no increased degeneration in the spines of long-time runners. 

In fact, there appears to be a beneficial effect with regards to running and low back pain, seeing as fewer runners report having back pain than do members of the general population.

However, there’s a lack of scientific work on causative factors and treatments for low back pain in runners.

Muscle tightness of the hip flexors and perhaps the hamstrings may play a role, but there’s a lot more work to be done.

Fortunately, as Dr. Charles J. Gatt Jr. writes in a 1997 book chapter on low back pain in runners,

“Most cases of low back pain are musculoligamentous [i.e. the result of a muscle or ligament strain, not structural damage to the spine itself] in character and have a relatively short, self-limiting course…In general, running does not cause lower back problems but may exacerbate existing conditions.”

Gatt goes on to describe how prolonged rest for back pain has been replaced with clinical advice encouraging patients to return to work and return to working out earlier, as this has been shown to be beneficial for lower back pain.

So perhaps the best advice if you have back pain is to:

• listen to your body
• moving back into running as soon as you can do it without pain
• look at other factors in your life that could be causing your back pain

And, as long as you aren’t too bothered by being a quarter-inch shorter after your runs, you can take comfort in knowing that your overall risk for back pain as a runner is lower than if you weren’t one!