Why do we stretch when we wake up?

Asked by: Solang Uk, Switzerland

When you sleep, your muscles lose tone and fluid tends to pool along your back. Stretching helps to massage fluid gently back into the normal position. Also, your muscles protect themselves from over-extension by inhibiting the nerve impulses as they approach their limit.

Over time, this safety mechanism becomes increasingly restrictive. Stretching briefly takes your muscles outside their normal range. This recalibrates the feedback mechanisms that determine their normal amount of motion.

Read more:

• Why do we rub our faces when we're tired?
• What happens in my body when i don't get enough sleep?

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