Recently, I started up a habit of stretching in the mornings and evenings, and I notice myself being extremely limber in the and extremely rigid in the mornings. I know the cause is inactivity, but what actually goes on in the muscles involved that makes them harder to stretch in the mornings and so much easier in the evenings?
They’re not warmed up. Actually, you should never stretch without first warming up your muscles: get the blood flowing into them. Stretching cold muscles can cause a tear (strain).
I presume you mean “cold muscles” metaphorically, because our muscles are almost 100 degrees F - which is pretty darn warm. Body temperature goes down a degree or two at night, and goes up a degree or two after moderate exercise, so it’s fairly stable. Unlike car engines, a rise in temperature is probably not needed for muscles to run smoother.
Here’s a link that hypothesizes several causes of morning stiffness. They’re addressing spinal stiffness, but i imagine there’s some similarities with other parts of the body.
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“We are the miracle of force and matter making itself over into imagination and will. Incredible. The Life Force experimenting with forms. You for one. Me for another. The Universe has shouted itself alive. We are one of the shouts.” – Ray Bradbury
Your body temperature is lowest when you first awaken, so your muscles are not as warm. Moreover, if you exercise the muscles, more blood flows into them. It is much better to stretch your muscles when you have more blood in them, as they are warmer and less likely to tear.
Exercising does cause minor trauma (tears), which is the cause for DOMS (delayed onset muscle soreness), but those are very minor and are repaired quickly, with the net result of stronger muscles. I usually jog a short bit first, maybe 10-20 minutes, until I feel “loosened up” and my metabolism shift over to high gear. Then I stretch and then I do some serious running. I stretch again when I’m done.
I would say because everyday you wakeup you’re getting older. <smiley face here if I knew how to do it>
Thanks much! 