Grade: 3
Right quadriceps gave out just above the knee as I was approaching #14 at GGP. Couldn't run and walking was a struggle. Tried to jog a few times over the next several minutes, and finally I could, then felt OK the rest of the way. However, it was quite sore later, and the next day I really couldn't go up and down stairs normally. Over the next few days it got somewhat better, to where walking normally was possible, but still feel it when I try to jog (or even pull on a sock).
Still an occasional twinge, but hopefully nothing worse.