An absence of load on spinal muscles can sometimes be just as weakening as a physical injury - so it's time to turn off the televison!

A recent study from Germany showed that an absence of load on spinal support muscles can sometimes be just as weakening as a physical injury for your lower back and back muscles. Thus, slumping in front of the TV or computer could deactivate muscles that support and protect your spine, triggering many otherwise inexplicable cases of lower back pain.

Ultrasound studies have shown that in most cases of lower back pain, either the lumbar multifidus muscles, which keep the vertebrae in place, or the transverses abdominis, which holds the pelvis together, or both, are inactive. Normally these back muscles work continuously to support and protect the lower back.

'Heavy lifting, whiplash or other injuries can damage and inactivate these lower back and core support muscles. This increases the risk of long term back pain, as people are then more likely to suffer sprains, or damage to the discs or other tissue in the back. However, only between 10 and 15 per cent of cases of back pain begin with such an injury. For the rest, the cause is often a mystery,' reports New Scientist.

A team from the University of Queensland in Australia has shown that the back and core support muscles of the bed-rest volunteers were inactivated in a very similar way to those of lower-back pain patients. Sitting around doing little can cause your back to act like it's been injured! Using magnetic resonance imaging, they showed that after eight weeks, the multifidus muscles of all 19 young male volunteers in the bed-rest study had wasted and become inactive.

'This is the first study to show that these muscles that protect your spine are switched off in de-loading,' says Julie Hides, one of the researchers. Slumping for hours in front of a computer or TV could have exactly the same effect, she suggests. This has important implications for lower back pain and the strength of our back and core muscles.

The study also found that switching these postural muscles back on isn't simply a matter of getting up and walking around. Six months on from the study, the multifidus muscles of some participants have still not recovered, even in those who exercised. However, therapy can help teach people to reactivate the support muscles using visual feedback from ultrasound scans.

'We know that bones and soft tissues need physical stresses to maintain vitality,' says Robert Moore of the Adelaide Centre for Spinal Research.