All workouts, especially tough ones, stress the body. You’re fatiguing, or tiring out, various muscles when you work out, which means you’re causing microscopic damage to muscle cells. Hormone and enzyme levels fluctuate, and inflammation actually increases, explains Chris Kolba, PhD, a physical therapist at the Ohio State University Wexner Medical Center in Columbus. The changes you’re causing can do your body a lot of good. They lead to muscle growth, fat loss, improved insulin sensitivity, reduced inflammation, better cardiovascular health, and overall healthier bodies. But you need to give your body time for those good changes to happen before you start stressing it out again. “This rest, called exercise recovery, is what allows people to [benefit] from their workouts,” Dr. Kolba says, allowing you to get the maximum benefit from every exercise session. “But you have to cause some damage to your body for it to adapt,” Dr. Rivadeneyra says. Repeated again and again, this process of stress and recovery is what results in improved health and fitness. RELATED: How Much Exercise Is Enough to Hit My Fitness Goals? “Overtraining can lead to overuse, which can lead to burnout and injury,” Dr. Leber explains. Common overuse injuries include iliotibial band syndrome, stress fractures, patellofemoral syndrome (runner’s knee), and muscle strains. RELATED: A Complete Guide to At-Home Workouts And if you’re starting a new workout routine, or upping the intensity of your exercise habits, the guidelines recommend doing so slowly, so muscles have a chance to adapt and for the lowest injury risk. RELATED: Weird Things Running Does to Your Body

Passive Recovery A complete cessation from exercise, passive recovery is synonymous with complete rest. (Okay — you can lie on the couch and kick up your feet for this one!) How much passive recovery your body needs depends on multiple factors, including your current fitness level and how intense your workouts are, Kolba says.

Active Recovery Active recovery means low-intensity, generally low-impact exercise that promotes blood flow and tissue repair without further stressing the body, Rivadeneyra says. “If you’re feeling fatigued from strength training, engage in a lower intensity cardiovascular bike ride or walk, which enables your body to circulate waste products caused by the rigorous activity,” Nicole Belkin, MD, an orthopedic surgeon at NewYork-Presbyterian at Columbia University Irving Medical Center in New York City, adds. Or try a gentle yoga practice to stretch out tired muscles. Think of active recovery as anything you can do without getting winded or fatiguing your muscles.

Cross-Training Cross-training lets you get the most bang for your workout buck. It means changing up the activity you do from workout to workout, so you are fatiguing different muscles during different workouts, Rivadeneyra says. For example, if you generally spend your workouts running, strength training, or boxing (even if performed at a high intensity) will stress your body in different ways. By allowing certain muscle groups to repair while others work, cross-training helps promote overall muscle health while minimizing the amount of passive and active recovery days needed.

Myofascial Release Myofascial release (sometimes called soft tissue therapy) includes massage and foam rolling. Performed immediately before and after exercise, it may help decrease feelings of delayed onset muscle soreness while speeding muscle recovery, according to research published in May–June 2015 in Current Sports Medicine Reports.Myofascial release can be a part of passive and active recovery days as well as cross-training workouts.

Nutritional Recovery The foods you eat provide your body with the building blocks needed to repair muscles and promote recovery, Kolba says. A whole-foods-based diet rich in antioxidants, whole carbohydrates, and lean protein can help trigger the right changes in your body between workouts, so your system is in better shape when it comes time for the next workout.

Sleep “This is a large part of the recovery equation,” Rivadeneyra says. During sleep, the body produces the majority of its growth factors and hormones that aid in daily muscle repair and recovery. Getting the recommended seven to nine hours of sleep per night allows those growth factors to do their work, he says.

Non-fitness-related stressors — such as poor sleep, relationship troubles, and working overtime — can affect how much rest and what type of recovery a person may need from a given workout, too. RELATED: The Work-Life Balance Conversation We Need to Be Having However, some fitter individuals may need more recovery because they are regularly exercising at a higher intensity. The schedule of the average gym-goer who exercises four or five days per week — combining a mix of high-intensity workouts, cross-training routines, and active recovery days — and takes the remaining two or three days off allows for proper recovery, according to Rivadeneyra. Fitter individuals may be able to use this strategy (alternating between high-intensity workouts, varied activity, and active recovery) six or seven days per week without taking any day completely off. What’s important to remember is that recovery looks different for everyone, Rivadeneyra adds. “For an elite marathoner, running 4 or 5 miles can be an active recovery workout,” he says. “For someone new to running, a 20-minute cycling session would be more appropriate for recovery.” At the same time, no matter what your overall fitness level is, it’s also important to pay attention to your individual needs. Even that elite marathon runner who can usually work out seven days per week, will likely need a little bit more recovery after, say, running a longer distance than usual, running a particularly hilly course that they’re not used to, or completing a race while recovering from a cold. RELATED: Should You Work Out When You’re Sick? That’s why it is critical to pay attention to both how you feel and how your body is responding to your workouts. Exercise plateaus (when you can’t seem to push yourself harder), mental fatigue, feelings of burnout, and extreme muscle soreness that lasts for more than three or four days are all signs that you need to increase your workout recovery, Leber says. Listen to your body and remember that your ideal workout recovery strategy will ebb and flow over weeks, months, and years. With additional reporting by Nicol Natale and Jessica Migala.