An investigation of lumbo-pelvic muscle changes due to physical inactivity (bed-rest) and their implications on muscular health (back pain) of humans
Final Report Abstract
The current project aimed to deepen our understanding of the effects of inactivity (prolonged bed-rest) on the lumbar spine and how this may relate to low back pain aetiology. This was implemented with 24 male subjects participating in 60-days bed-rest as part of the “2nd Berlin BedRest Study”. In the course of the project it became possible to include data from two other bed-rest studies. As part of the original proposal, the main focus laid upon the musculature and its relation to low back pain. Contrary to initial hypotheses, we found that the lumbar musculature recovered its size occurs within 90-days after prolonged bed-rest. The recovery of muscle size after bed-rest has, to the best of our knowledge, not been investigated by other research groups and our results from the lumbar spine and other body regions suggest that this parameter recovers without specific intervention after bed-rest. The incidence of low back pain was highest in the first week of prolonged bed-rest followed by the first week afterwards. Subjects who reported low back pain in the weeks after bed-rest, showed a significantly greater extent of lumbar multifidus atrophy during bed-rest. Bed-rest resulted in the fastest rates of muscle atrophy in the lumbar multifidus at the lower lumbar spine and erector spinae at the upper lumbar spine. Inclusion of assessments of the lumbar intervertebral discs resulted in some unexpected findings, with the main finding being that increases in lumbar intervertebral disc volume, height and intervertebral length did not completely return to prebed-rest levels 153-days after 21-days bed-rest or 2-years after 60-days bed-rest. Furthermore, the incidence of low back pain after bed-rest was associated with a greater extent of posterior disc height increase at the lower lumbar spine. The findings of an association between muscle atrophy and disc morphology changes during bed-rest and low back pain after bed-rest are important because they help to provide support for the “causality” of certain factors in low back pain. The results of the current project help to define the pattern of deficits that occur in deconditioned individuals (such as after medical bed-rest, immobilisation and astronauts) and help guide their rehabilitation. The results also help to understand the physiology of muscle atrophy and intervertebral disc unloading and also define exercise protocols to best prevent deconditioning of the lumbar spine during inactivity.
Publications
- (2010): Countermeasures against lumbar spine deconditioning in prolonged bed-rest: resistive exercise with and without whole-body vibration. Journal of Applied Physiology, 109(6):1801-1811
Belavý DL, Armbrecht G, Gast U, Richardson CA, Hides JA, Felsenberg D
(See online at https://dx.doi.org/10.1152/japplphysiol.00707.2010) - (2011): Limited effect of fly-wheel and spinal mobilization exercise countermeasures on lumbar spine deconditioning during 90d bed-rest in the Toulouse LTBR study. Acta Astronautica
Belavý DL, Ohshima H, Bareille M-P, Rittweger J, Felsenberg D
(See online at https://dx.doi.org/10.1016/j.actaastro.2011.05.015) - (2011): Muscle atrophy and changes in spinal morphology: is the lumbar spine vulnerable after prolonged bed-rest? Spine 36(2): 137–145
Belavý DL, Armbrecht G, Richardson CA, Felsenberg D, Hides JA
(See online at https://dx.doi.org/10.1097/BRS.0b013e3181cc93e8) - (2011): The effects of rehabilitation on the muscles of the trunk following prolonged bed rest. European Spine Journal 20(5): 808-818
Hides JA, Lambrecht G, Richardson CA, Stanton WR, Armbrecht G, Pruett C, Damann V, Felsenberg D, Belavý DL
(See online at https://dx.doi.org/10.1007/s00586-010-1491-x)
