This would happen to me. I played soccer for over 10 years, have worked out consistently since then, and have taken up running the past year and a half. Then today, I go to play soccer with my rec team. My first PLAY, I pull my quad. Bad. I am now iced and on the couch. It seems stretching really is important before you just start sprinting for the ball. Also, not doing any hardcore running for a week to "cool off" from a few intsense athletics days, does not mean you are protected from injury. It seems that not using your muscles is actually bad when you suddenly start doing it again.
Great. Now I am out of commission for a few days, which is hard for this work-out-aholic. It also hurts my working, since I am on my feet and walking around all during work.
Oh, and on another note, I have not seen Toy Story 3 but have a few opportunities this week to see it either with people or by myself.
Here's "Just Tap It" in healthier days...