A thorough warm-up is essential for both effective strength-training and effecient intraday recovery...
Light exercise is the best tool for improved recovery in-between hard workouts. Some light jogging, hiking, swimming or easy Parkour followed by a thorough stretching session is perfect. Along those lines, I have decided to put together the most useful and broad-spectrum exercises into a standardized warm-up for our WOD, and this by itself will be an excellent rest-day activity. General calisthenics performed until you raise your core temperature over a wide-range of movement options are an excellent way to flush your body of accumulated toxins. Each exercise should be performed in a rep-range that allows for a raise in body-temperature, heart rate and range-of-motion, without accumulating undue fatigue. Substitutions for each exercise are fine, as everybody has a different level of fitness, so if Dips are too hard, then perhaps try push-ups, or knee push-ups. If 10 is too many, than perform as many as possible within the range of an effective warm-up is concerned. As you fitness improves, your warm-up will mirror this improvement. The standardized warmup will be as follows:
Run 200 meters forward, 100 meters backward, 50 meters side shuffle to each direction.
20 Steps Quadrupedal Movement (Monkey Style)
20 Steps Lateral Bounding
10 Body Rows
10 Skull Crushers
45 Second L-Sit (Hanging or Posted)
2 x :30 Samson Stretch Each Side
Rest as needed between each exercise, keeping in mind that the goal isn't to kill yourself, but rather to facilitate a raise in core-temperature and improve the pliability of your muscles and connective tissues. If you do this on a rest day, it can be followed by a good session of stretching (issue 3 of the Performance Menu, with an excellent feature on flexibility). If it is before the workout, leave the stretching for the very end of the entire workout session.
For some more info on the benefits an effective warm-up, check out this issue of the Crossfit Journal