[JohnnyTooBad]

What's up with the leg muscles getting all twisted up? This is not cramping, and doesn't happen when I'm on the bike or being active... just sitting around. My hamstring will get all torqued up and hurt like a sonofabi+c#. It happens when my legs are bent, usually sitting in a chair with my foot underneath me, and I have to instantly straighten my leg out. The pain is pretty extreme. I can make it happen by pointing my toes (opening the ankle joint all the way) and using my hamstring to bend my leg as far as I can or flexing the hamstring (doesn't usually happen when it's passively being bent, such as pulling my heel to my butt with my hand). Last night, I was sitting on a bench, and had my left leg across the top of my right leg (ankle up on the leg, knee out to the side - clipping toe nails), and the muscle on the inside of my left leg did it (groin muscle?).

Why does this happen?

 

[JCavilia]

Your description isn't too precise,

but it sounds like it is in fact cramping. Muscles don't "twist" or get "torqued up' (not sure what that means) -- they contract spasmodically; that's a cramp. It's caused by lots of things, and it's not always clear what. Have you been riding a lot, and hard? Try some massage, maybe with heat, and make sure you're eating and hydrating properly. It sounds exactly like cramping of muscles that are fatigued and somewhat injured from overwork.

 

[JohnnyTooBad]

I do commute by bike, usually 3-5 times a week, 10.5 miles each way, and ride pretty hard. It may be cramping, but it's not the kind of cramping I experience when I over do it on a long ride. Maybe it's more of a spasm. I stay pretty hydrated, but this seems somewhat unrelated to cycling because I can sit here at my desk or at home, any time, and make it happen, even if I haven't been on the bike or done anything strenuous in a couple of days.