I've been playing around with Crossfit for the last few months. I wouldn't say that I'm "doing" crossfit, because I'm not nearly as religious about it as the true converts. But, I've adopted the main Crossift site's warmup as my own, and I often do a (scaled) version of the main-site WOD. I also know what WOD, AMRAP, "metcon," and "rhabdo" stand for, and why "doing Cindy's little sister" isn't as pornographic as it sounds.
Anyhoo, I went to my first organized Crossfit class on Saturday. Much of the hour-long class was devoted to warmup, exercise demo, drills, and cooldown, but the 16 minutes of actual workout had me absolutely knackered. It was one of those workouts -- and Crossfit has a lot of them -- that doesn't *sound* like it should be too bad: 7 minutes, AMRAP of squats, burpees, push presses, and pullups; 2 minutes rest; 7 minutes AMRAP as above.
The first round flies by. The second round starts to hurt. A lot. Then the sadistic SOB with the stopwatch tells you you're only half way. The first round after the rest period, you feel like you're trying to do squats through molasses. The second round, you're regretting every ounce of breakfast. The third round, you're close to seeing it again.
And, once you're done, you realize that your bright idea of jogging the 2 miles to class has a major flaw: when you live at the top of a hill, what goes down must come back up.
Thank the Flying Spaghetti Monster for rest days.