A little history. I have avoided stretching, except for dynamic stretches before every run... you know, running drills, skips, lunges, butt kicks, etc.. Anyway, I decided to try static stretching for a few days. Nothing fancy... toe touches holding for 20 seconds, lunges holding for 20 seconds to stretch the hip flexor, etc.. Now, I'm sore from stretching. What's going on?
So, my question: When you stretch, what exactly is happening? Is the muscle in a state of constant contraction and stretching restores it to a relaxed position? If so, why does it hurt the next day? Is the muscle filled with scar tissue and stretching tears that tissue, letting it stretch more? Or, does stretching over time make your muscles longer? That doesn't seem likely to me. So what's going on?