A screenshot of the 3-D running simulation. Photo: Ohio State University

Avid runners who frequently suffer from lower back pain after going for a jog may finally find some relief in the results of a new study published this week in the Journal of Biomechanics.

Researchers from Ohio State University’s Wexner Medical Center used motion detection technology and force-measuring floor plates to get a better look at the muscles at work when in movement.

Eight healthy young adults were recruited for the experiment, which involved the participants running around an indoor tracked lined with the force-measuring floor plates. The plates recorded the magnitude and direction of force as the runners pushed off the ground.

The team used the data to produce 3-D simulations of the runners, which showed exactly how their bones and muscles reacted as they ran. The simulations allowed the researchers to manipulate different muscle groups to see how performance would change depending on different levels of strength and stability.

“That allows us to examine how every bone moves and how much pressure is put on each joint,” said Ajit Chaudhari, associate professor of physical therapy and biomedical engineering at Ohio State University Wexner Medical Center, who led the study. “We can then use that simulation to virtually ‘turn off’ certain muscles and observe how the rest of the body compensates.”

They progressively increased the weakness of four deep core muscles, both individually and together through the simulations. Results of the simulations showed that if the deep core muscles weren’t strong enough to stabilize a runner’s core, surface core muscles (like the abs) had to compensate.

The extra load on the surface core muscles causes strain on the spine, which ultimately leads to lower back pain, the study showed.

Out of the four deep core muscles observed in the study, the deep erector spinae required the largest compensations when weakened individually (up to a 45 percent increase in compensating muscle force production), which suggests it may contribute the most to controlling running mechanics.

“When your deep core is weak, your body is able to compensate in a way that allows you to essentially run the same way,” Chaudhari said. “But that increases the load on your spine in a way that may lead to low back pain.”

Many athletes tend to focus on strengthening their abs and other surface core muscles, but may unknowingly be neglecting their deep core. The researchers suggest adding exercises like planks to their routine to help stabilize their core.