While home for the holidays, I extended an offer to my sister, who does a lot of work with book editing and is quite if not more involved with exercise than myself, to write a guest post. Here's her post on recovery exercises; great to incorporate into your routine after a particularly rough day.
After an especially intense workout, it’s often necessary to give your body a break. While you may be tempted to curl up on the couch while you let your sore muscles relax, the best strategy may actually be engage in low-intensity exercise (“active” recovery) instead of forgoing your workout altogether (“passive” recovery).
Muscles become exhausted and broken down during exercise, and recovery days allow them to heal and grow stronger. Although it might seem logical to let your body rest completely during these off days, research suggests that sticking with light exercise may be more beneficial.
According to this site I found, the purpose of active recovery workouts is to “exercise at an intensity that is enough to stimulate circulation and trigger certain endocrine responses, but lightly enough to avoid demanding more recovery from the recovery workout”
A study in the journal Medicine & Science in Sports and Exercise found that light workouts on recovery days reduce the levels of lactic acid in muscles more quickly than rest alone. There are psychological benefits to active recovery, as well: doing just an easy workout instead of skipping it altogether can help you relax, ease stress, and serve as a confidence booster.
You can also use active recovery days to try a new workout. If you’re used to running, try swimming, which allows you to rest your legs and utilize your upper body (as a low-intensity sport, swimming can give your joints a break, too). It’s also important to increase your stretching time during recovery days.