Countermeasures against lumbar spine deconditioning in prolonged bed rest: resistive exercise with and without whole body vibration

Abstract

To evaluate the effect of short-duration, high-load resistive exercise, with and without whole body vibration on lumbar muscle size, intervertebral disk and spinal morphology changes, and low back pain (LBP) incidence during prolonged bed rest, 24 subjects underwent 60 days of head-down tilt bed rest and performed either resistive vibration exercise (n = 7), resistive exercise only (n = 8), or no exercise (n = 9; 2nd Berlin Bed-Rest Study). Discal and spinal shape was measured from sagittal plane magnetic resonance images. Cross-sectional areas (CSAs) of the multifidus, erector spinae, quadratus lumborum, and psoas were measured on para-axial magnetic resonance images. LBP incidence was assessed with questionnaires at regular intervals. The countermeasures reduced CSA loss in the multifidus, lumbar erector spinae and quadratus lumborum muscles, with greater increases in psoas muscle CSA seen in the countermeasure groups (P ≤ 0.004). There was little statistical evidence for an additional effect of whole body vibration above resistive exercise alone on these muscle changes. Exercise subjects reported LBP more frequently in the first week of bed rest, but this was only significant in resistive exercise only (P = 0.011 vs. control, resistive vibration exercise vs. control: P = 0.56). No effect of the countermeasures on changes in spinal morphology was seen (P ≥ 0.22). The results suggest that high-load resistive exercise, with or without whole body vibration, performed 3 days/wk can reduce lumbar muscle atrophy, but further countermeasure optimization is required.

Disc herniations in astronauts: What causes them, and what does it tell us about herniation on earth?

“…The gellike material (d) is fat tissue Eur Spine J (2016) 25:144-154 145 could explain increases in spinal length despite swelling of the IVD, but flattening of the lumbar lordosis has not been consistently found in bed rest studies. At the end of prolonged bed rest, decreases [17,21], no change [14,22], and increases [16] of the lumbar lordosis have been seen. This physical mechanism (Fig.…”

“…2 Expansion of the lumbar L4/5 IVD due to spaceflight simulation (bed rest). MR images of 23 subjects of an earlier 60-d bed rest study [21], and have not been published previously. In this dataset, whole IVD volume increased by mean (SD) 6.0 (3.3) %, IVD height increased by 7.0 (3.6) % and the anteroposterior IVD dimension decreased by 1.6 (1.9) %.…”

Hypertrophy in the cervical muscles and thoracic discs in bed rest?

“…Alternatively, astronauts are quite busy with mission tasks, and one may argue that their usage of their neck muscles in these tasks may well prevent atrophy. Furthermore, predicting muscular changes in bed rest on the basis of existing findings in spaceflight can be difficult: the psoas muscle at the lumbar spine was observed to atrophy after spaceflight (10), but studies in bed rest have shown either significant (2,32) or nonsignificant (3,8,23) increases in the size of this muscle. Thus it is difficult to predict, on the basis of existing data, whether muscle atrophy may occur at the neck during bed rest.…”

“…Lumbar spine lengthening and hypertrophy of the lumbar invertertebral discs is seen in prolonged bed rest (2). The question remains open as to whether similar hypertrophy occurs at the cervical and thoracic intervertebral discs.…”

Terrestrial neuro-musculoskeletal rehabilitation and astronaut reconditioning: Reciprocal knowledge transfer

“…Countermeasure studies have been conducted during bed rest (e.g. Belavy et al, 2010;Blottner et al 2006;Miokovic et al, 2011), which provides an analogue of microgravity; a useful tool given the methodological constraints of conducting studies inflight (see below regarding methodological challenges). Members of the Reconditioning Topical…”