Running exercise strengthens the intervertebral disc

Abstract

There is currently no evidence that the intervertebral discs (IVDs) can respond positively to exercise in humans. Some authors have argued that IVD metabolism in humans is too slow to respond anabolically to exercise within the human lifespan. Here we show that chronic running exercise in men and women is associated with better IVD composition (hydration and proteoglycan content) and with IVD hypertrophy. Via quantitative assessment of physical activity we further find that accelerations at fast walking and slow running (2 m/s), but not high-impact tasks, lower intensity walking or static positions, correlated to positive IVD characteristics. These findings represent the first evidence in humans that exercise can be beneficial for the IVD and provide support for the notion that specific exercise protocols may improve IVD material properties in the spine. We anticipate that our findings will be a starting point to better define exercise protocols and physical activity profiles for IVD anabolism in humans.

Long-term running in middle-aged men and intervertebral disc health, a cross-sectional pilot study

“…L4-L5 and L5-S1) have been found to be the most common sites for disc degeneration [22] and disc herniation [23]. In contrast to our findings, Belavý et al [11] found that there was no difference in Pfirrmann grades between participants who were not regularly involved in sport compared to runners. Their population was an average of 20yr younger, and morphological changes due to age and activity may have not yet manifested themselves (at least not on MR images).…”

“…T2-time and ADC) did not differ between groups, despite differences in Pfirrmann grade. Previously, Belavý et al [11] found significantly longer T2-times in runners compared to non-athletic individuals. The discrepancy between our findings may be explained by the age difference of our participants.…”

“…smaller vertebral body height and a larger IVD height in the runners. Belavý et al [11] also found that long distance runners, but not the joggers, nor the participants in the non-sporting group, exhibited a greater IVD-to-vertebral body height ratio and referred to this as 'IVD hypertrophy'. This finding is interesting because it is commonly accepted that lumbar IVDs decrease in height with advancing age [24] as a result of morphology changes and the reduced ability to bind water [7].…”

“…Marinelli et al [10] showed that T2 relaxation time, an intrinsic property of tissue that can be measured with MRI, significantly and strongly correlated with water content in the IVD. Belavý et al [11] used T2 relaxation times to demonstrate that chronic runners aged 25-35yr exhibited better IVD tissue quality (i.e. hydration) compared to non-physically active controls.…”

“…This could be interpreted as being detrimental to the structure of the disc, or as a benefit to the metabolic processes. Therefore, two competing theories concerning loading of the spine and its consequences to IVD health were considered in this study: 1) cyclic loading is beneficial for IVD tissue and leads to hypertrophic changes that make the disc stronger [11], and 2) mechanical overload produces localized trauma and tissue damage, which outpaces the ability of a disc to repair itself and leads to accelerated degradation [14]. Both theories are based on robust previous research, but the implications are conflicting.…”