I work in a cubicle maze. Two cubes over, there's this guy in his 40s who groans so loud when he stretches in the morning. I always have to stretch in the A.M., too, but I try really hard to keep my groans quiet to avoid bothering my cube neighbors.
Anyhow, I started wondering why we all do this. I Googled it and the only information I could find was crap like Yahoo answers and this web site for kids:
http://www.whyzz.com/why-do-we-stretch-after-waking-up
These answers about "getting blood flowing back to the heart" or "waking up your muscles" don't cut the mustard. You see, I run about 4 miles to work every morning. Yet, I continue to have involuntary urges to stretch all morning until around 1pm. If blood flow or muscle waking were the reason, my morning run would have taken care of that. Therefore, these theories seem b.s. to me.
Can anyone explain this phenomenon better?
PS. My 5k PR is 14:18.