As cold and flu season approaches, this question resonates with every trainer, instructor, and participant. All too often a few days off to feel better leads to a downward spiral of getting out of the fitness habit. Those who have had prior battles with the issue are resolute that they will work out no matter what. Unfortunately, some things require that we take a short break. Injuries, obviously, require rest. Some illnesses also demand down time in order to go away.

Much research, including a recent study by the Academy of Sports Medicine, indicates that there is no reason to stop working out when you have a cold. The above/below the neck rule applies. If your symptoms are above the neck, i.e. sniffles, sore throat, colds, etc. it is okay to work out. You may not have your usual stamina or strength, but fighting through the illness may actually shorten its duration. Carefully assess how you feel as you progress through your class, run, or workout and listen to your body. Drink plenty of fluids and allow additional recovery time if you are feeling weak or achy.

If your symptoms manifest lower in the body, i.e. nausea, vomiting, difficulty breathing, then take a few days off. NEVER work out with a fever. These illnesses place extra demands on virtually every system in the body. Continuing to work out through these symptoms will probably prolong the illness. Be careful, specifically with stomach illness, to stay hydrated. You may not feel like eating, but using sports drinks and clear liquids to maintain the proper fluid intake is critical. Avoid drinks that are sweetened either by sugar or artificial agent as they too may aggravate your already compromised system.

When you do return to the gym you need to lighten your load a bit, especially with cardio. Depending on your energy level and the extent to which you are hydrated—and don’t return until you are re-hydrated, you will likely be able to come back at about 80%. That’s a twenty percent reduction in time, intensity, and weight, depending on the nature of your workout. If you were down for an extended period of time (5-7 days), you may need to return with a day of rest between each session for the first week. Do not forsake a good night’s sleep during that first week after an illness. That is one way to virtually guarantee that your weakness will linger.

Listen to your body, drink lots of water, and don’t rush the healing. If you do not permit yourself time to get well, you will likely relapse. Within two to three weeks you should find that you have reclaimed your previous strength and stamina. If you seem to have recurring instances of illness for more than a month, you should definitely see your doctor. You may need more than water and rest to kick whatever has infected you. When you are well, get back to the gym, track, dojo, etc. and require yourself to be active for at least 15 minutes a day for 16-21 days STRAIGHT. This will help re-establish your workout habit and give you a jump start on your road back to improved fitness. Then, you can safely resume your normal workout pattern. Now you know!