December 4, 2021

Do Astronauts get back pain

Do Astronauts get back pain

Do Astronauts get back pain?

Why is this research relevant to physiotherapy?

More than 50% of space travellers develop low back pain, headaches, poor concentration, nausea and vomiting.

In a weightless environment, the following adaptations are observed:

  • Loss of bone and muscle mass (eg multifidus and other spinal muscles)
  • Decreased spinal curves as discs imbibe (absorb) fluid and get thicker
  • Body height increases by 5-8 cms
  • Body fluids are redistributed generally towards the head.

The body changes in a weightless environment are very similar to bed rest studies on Earth where participants are lying down for 60 days and are unable to stand for any reason. These changes therefore influence how bone and muscle responds to exercise and weightbearing.

On Earth, our bodies have adapted to gravity. It is a healthy load providing we can control the spinal position with the appropriate muscles to stabilise the spine, and do not fatigue.

When Space travellers return to Earth, they are vulnerable to back pain as they are unable to distribute load and forces normally until they learn to reload their spine appropriately, especially with lifting. It is the muscle multifidus that wastes and becomes dysfunctional within a weightless environment (including bed rest). This muscle controls the curves in the spine to help distribute load.

The multifidus muscle also becomes dysfunctional with periods of back pain, poor habitual postures (especially sitting in front of computers for 8-10 hours per day) and poor lifting positions. The resulting muscle imbalances that contribute to low back pain in space travellers, athletes, office workers and the general population alike can be addressed through physiotherapy and a motor control program. This involves learning to control spinal position to distribute load effectively and includes an endurance component to prevent fatigue and prevent further episodes of low back pain.

Reference: Hides, J. No load, big problem: back pain from outer space. Physiotherapy In Motion, September 2010.