MEDICAL MISCELLANY

WHY do we change position in our sleep?

IT’S fairly common to wake up on the same side you fell asleep on, but don’t be fooled — you have moved.

During stages of the night where sleep is lighter, you’ll make small motions, such as moving a leg, around five times an hour, with whole body shifts twice an hour, according to a leading sleep neuroscientist, Professor Jim Horne. ‘If you don’t, then nerves can get compressed, causing numbness and pins and needles.’

He adds: ‘Complete sleep cycles last about 90 minutes and there is a tendency for whole body movements to be more evident at their end. But movement can occur beforehand, mid-cycle — even more so towards the end of a night’s sleep.’