Should I exercise when I'm sick?

As the flu season strikes, many of us wonder whether it's safe to train when we're feeling lousy.

A common question I hear from people is, “Can I exercise when I’m sick? Is it bad or will it help me get better sooner?”

“Sickness” or “illness” can cover many types of ailments or conditions so my focus here will be on common colds and flu as we enter the flu season, which is generally considered to be from May to the end of winter. These colds and flu’s are broadly classed by the medical community as Upper Respiratory Tract Infections or URTI.

If you have a more serious illness you should definitely not exercise, and focus on recuperation. When illness debilitates you, the body needs to use its strength and resources to fight off infection , so always seek clearance from your doctor before recommencing your exercise program.

If the ailment is less serious (ie a cold or flu), which means the symptoms and effects are unpleasant but not debilitating then you may do some exercise. There is not a great deal of research on this topic and every person and virus can be different but a common rule of thumb used is the neck check:

Above neck symptoms only - free to exercise (use the guidelines below). These symptoms include runny nose, sneezing, sore throat, mild headaches.

If below neck symptoms are present – swollen glands, fever, chest cough, muscle and joint aches, all on the trunk and limbs - then it is best not to exercise.

In general the research says that light exercise when you have a cold can make you feel better and not do any extra damage. The thinking here is that light exercise clears airways and enhances circulation, and this can speed healing via delivery of good nutrients in the blood stream. It may also elevate mood - in other words, make you feel better.

Moderate exercise can boost the immune system and this can be a benefit both in the immediate term as well as longer term.

So the key?

Back off the intensity but be active (walking may be a good option) and there may be physical benefits, but keep the intensity low to keep the heart rate down, under 120bpm as a guide.

Maintaining immune health, from the Exercise Immunology Review

EIR is the official publication and position statement of the International Society of Exercise and Immunology

Practical guidelines for you to prevent infections:

• Keep vaccine updated.

• Minimise contact with sick people.

• Keep a distance in public from people sneezing coughing or with a runny nose.

• Wash hands regularly.

• Limit hand to mouth contact if you feel the onset of symptoms.

• Do not share drink bottles, cups or towels, especially bathroom hand towels.

• Protect your airway from direct exposure to very cold dry air - flights or morning air.

• Avoid getting cold or wet after exercise.

• Get at least seven hours sleep nightly.

• Keep life stress to a minimum.

Guidelines for exercising when sick

• Drop the intensity and exercise at a low to moderate level (ie heart rate below 120bpm).

• If symptoms are above the neck, you are OK to train.

• Drink plenty of fluids.

• Keep from getting wet whilst exercising - avoid the rain and swimming.

• Minimise other stress in your life.

• If symptoms do not get any worse, then light exercise may be continued until you feel better.

• When symptoms have passed you may gradually lift the intensity (aim to keep HR under 150pm).

• If symptoms (fever or headaches or stiffness/soreness and excessive fatigue) were severe and you ceased training for a period:

• Wait 1-2 days before recommencing exercise after symptoms have cleared.

• If you had four days sick then take four days to return to normal exercise - step it up gradually over the number of days you were laid up.

• Be aware that intensity is the key - limit the intensity as you reintroduce exercise. If you are not handling the harder sessions then back them off - listen to your body. Take rest days as you need them.

• Always see your doctor for specific advice on your condition.