Get Active To Prevent Disc Problems
Ryan Cross, B.A. Hons (Kin), MScPT, FCAMPT
Registered Physiotherapist in Sarnia, Ontario, Canada
There are many different reasons to exercise. Exercise can improve our cardiovascular system, lifting weights can make our muscles grow stronger, and in other cases, exercise can improve happiness and brain function. Degenerative disc disease is a normal part of aging, but exercise may be able to keep our discs strong and hydrated. New research is now pointing to exercise as a way to improve the quality of the intervertebral disc (IVD). Currently, most research being done uses data from animal models, and those results suggest what might be helpful for the human disc. In a study published in Science Reports, researchers set out to determine if regular exercise can “strengthen” the disc in humans (Belavy et al, 2017). They hypothesized that people who run regularly will show better IVD tissue quality than people who are healthy (with no prior spinal injury) but not currently active.
For this study, a total of 79 participants were recruited. Joggers (20-40 km per week), long distance runners (50km+ per week) and no sporting background. Individuals in the study were between the ages of 25- 35 to reduce the impact of normal age-related changes. The quality of the IVD tissue was determined using MRI scans. Specifically, the researchers looked at hydration and glycosaminoglycan content that was displayed on those scans. Researchers were also looking into what types of physical activity are likely beneficial for IVD. In order to do so, they explored the relationship between normal physical activity, as measured by objective accelerometry, and IVD characteristics.
After scanning, subjects were given a monitoring tool that measured their activity (acceleration). Participants were instructed to wear the monitor during all waking hours. To determine which activities generate what accelerations 10 individuals performed a graded treadmill test at speeds of 0.5 m/s, 1 m/s, 1.5 m/s, 2 m/s, 2.5 m/s, 3.0 m/s and 3.5 m/s while wearing the monitoring tool. Participants also performed 10 consecutive jumps maintaining the knee and hip at near full extension, similar to hopping on one leg, but bilaterally (Belavy et al, 2017).
The results of the study showed that long-distance runners and joggers showed significantly higher levels of hydration in lumbar intervertebral discs than the non-athletic individuals. Increased hydration was seen in all individual vertebral levels. Long distance runners also showed greater IVD hypertrophy (height of the IVD relative to the vertebral body). The lower lumbar levels showed the greatest effect of IVD hypertrophy. These benefits were consistent between males and females in this study. Researchers were also able to identify which types of physical activity will likely benefit the IVD. Results showed that walking or jogging at 2 m/s would most benefit the IVD. Slow walking, fast running, and jumping did not produce the effects that appear to benefit the IVD. This shows that there might be a “window” of intensity that is beneficial to the disc.
In general, a healthy IVD is maintained by the cells in the nucleus pulposus (nuclear chondrocytes). Under proper loading and hydrostatic pressure, these cells produce proteoglycans (hydration). Degenerative disc disease can happen when hydrostatic pressure is reduced due to damage to the extracellular matrix, cellular degeneration of the matrix (e.g. due to smoking) or prolonged overloading and shear forces. This can cause the cells to stop producing proteoglycans. When this continues, the gel-like nucleus pulposus becomes a more ﬁbrous tissue. (Belavy et al., 2016)
The findings of this study should get active people excited for a number of reasons. First, it shows that being active helps keep your IVD hydrated and strong. It also provides evidence that axial loading is not detrimental to the IVD, in fact, when loaded properly it benefits the disc. Furthermore, I believe the study findings should give everyone confidence that getting active is beneficial for back health. Not only is running beneficial for quality IVD, you don’t need to reach elite level speeds or training. Fast walking or slow jogging produced a load that seems to be most beneficial for the IVD. Therefore, going for a brisk walk a few times per week is a great starting point. Plus, you are keeping your lumbar discs hydrated.
You Might Like:
Belavý, Daniel L., et al. “Running exercise strengthens the intervertebral disc.” Scientific Reports 7 (2017).
Belavý, Daniel L., et al. “Can exercise positively influence the intervertebral disc?.” Sports medicine 46.4 (2016): 473-485.