2007-09-08 13:07:35 · 3 answers · asked by Chef Lau 2 in Science & Mathematics ➔ Biology
When we sleep, our heart rate slows and blood pressure drops some too. This allows circulation to slow and blood pools in small veins called veinules. Stretching is an instinct to squeeze and flex muscles which in turn put pressure on the vienules move the pooled blood again. Yawning is an instinct to (this sounds funny) stretch your face, because fatigue leads to the same circulation decline. Good question.
2007-09-08 13:18:23 · answer #1 · answered by Derail 7 · 3⤊ 0⤋
well...it feels good. if you've been sleeping for several hours in one (or maybe a several, depending on how you toss and turn) position it feels good to have a stretch upon waking.
2007-09-08 13:12:14 · answer #2 · answered by Anonymous · 0⤊ 0⤋
maybe because your muscles have been still for so long while you slept ... plus, doesn't a nice stretch in the morning feel great??
2007-09-08 13:12:56 · answer #3 · answered by saf913 2 · 0⤊ 0⤋