We all know exercise is good for us, and there is a lot of research out there supporting the idea that regular exercise can strengthen the immune system in the long run (Nieman et al). Unfortunately, getting sick once in a while is unavoidable, and anyone who trains regularly will someday have to decide whether to train through an illness or take a break and recover. What's the best way to work this out?
Sweat it out or sleep it off?
The general rule is that if the symptoms are above your neck, you're safe to exercise. Symptoms like a runny nose, stuffy head and a scratchy throat aren't going to pose serious problems during a workout, and you're unlikely to exacerbate the common cold by getting active. You might want to tone down the intensity or the duration of your workout, and if you don't feel like hitting the gym, not being at your best is a very reasonable excuse not to go.
Below the neck is a pretty general description, but if you have any signs of a more serious or systemic illness, which might include a raised temperature, lung congestion, body aches, or gastric symptoms, the only exercise you should be doing involves your fingers and a remote control. Pushing yourself when you're this unwell is likely to make you feel worse, and cause your illness to drag on longer than it otherwise would.
Should you Train with a Cold?
If you've decided to try and sweat out the lurgy, there are still some important dos and donts that are worth taking into account.
Firstly, and very importantly, be considerate of others. This means that if you are in the contagious stages of a cold – runny nose, sneezing, coughing – you need to avoid spreading it to other people. This means no weights or machines at the gym and no team sports. Avoid any exercise where you will be in close quarters with other people, or sharing equipment.
Marathon Training when Sick?
Take it easy. If you feel up to it, by all means, go for your full workout, but be aware that a number of studies have shown that extremely strenuous activities, particularly endurance sports, can actually depress your immune system (Gleeson 2007). If you're an endurance athlete, try cutting down the duration and intensity of your training until you're back on top.
Bodybuilding Training while Sick?
If you prefer resistance exercise, be aware that straining to lift heavy will increase the pounding in your head and the pressure on your sinuses. This is not the kind of pain you want from a workout, and there's every chance that you're going to have a very unpleasant time. You're not going to make any PBs while your body is dedicating energy to fighting illness, so take it easy. Lifting lighter and upping your reps will make for a more pleasant workout and also improve your muscular endurance, which is an important part of functional fitness.
Does Exercise Help a Cold?
The good news that some types of exercise can actually help relieve or take your mind off the symptoms of a cold, and leave you feeling better than when you started.
Walking and jogging are great when you're not well because it is so easy to adapt the intensity so you're not doing more than you can handle. Apart from getting you out of the house, walking and running open up the airways, so a few laps round the block can act as a natural decongestant. On top of this, you're unlikely to come into close contact with many people, so there's little risk of passing your illness to others.
Benefits of Yoga
Yoga and Tai Chi can be a great way to keep moving when you're feeling rotten, and believe it or not, these types of exercise have been shown to have immune system benefits and to reduce the body's inflammatory response (Morgan et al 2014). There are plenty of tutorials and videos online, and these types of low impact exercises are easy to do in your own home.
Exercise and Recovery
Whether you decided to take it easy or stopped training completely, it's important to build up to your normal training routine gradually. Even if you've retained the fitness and strength to jump back in at full speed, placing your body under stress, as is the goal of adaptive training, can slow full recovery or even cause the illness to relapse. Loss of condition is a concern where the training break was longer. Trying to train at your previous level may be very difficult, or even impossible, and making the effort has a high potential to cause injury. Don't punish yourself for being sick, take it easy and be aware that your limits may have changed.
Obviously, preventing illness in the first place is the best way to minimise the time you spend away from training. Training places demands on the body, and it is easy to become run down and prone to illness without replacing what your workouts are taking out. Supplements can help you avoid illness, and knowing that you're doing everything you can to safeguard your health brings valuable peace of mind. Important immune supplements for active people include:
Glutamine – One of the most abundant amino acids in the muscles, glutamine is depleted during vigorous exercise. This amino plays a vital role in the immune response, and low glutamine levels have been shown to impair the body's ability to fight infection and illness (Calder & Yaqoob 1999).
Multivitamins – Low levels of vitamins and minerals can cripple the immune system, which relies on these substances as cofactors in a large number of germ-fighting reactions. Try a vitamin rich greens supplement, easily digested and packed with antioxidants for optimum vitality.
Fish Oil/Omega-3 – What doesn't omega-3 do? It does almost everything, including boosting the immune system after a workout, when you're at your most vulnerable to illness (Gray et al, 2012). A daily omega-3 supplement also offers protection to your heart and joints, and has even been shown to improve mental functioning and fight depression.
For the majority of people, regular exercise is one of the best choices they can make to improve their health and wellbeing, however anyone who is suffering, or thinks they might be suffering from a serious or chronic illness needs to speak to their doctor before embarking upon, or continuing with any exercise program.
Calder PC, Yaqoob P. Glutamine and the immune system. Amino Acids. 1999;17(3):227-41.
Gleeson, M (2007). Immune function in sport and exercise. Journal of Applied Physiology. Vol. 103 no. 2, 693-699
Gray P, Gabriel B, Thies F, Gray SR. Fish oil supplementation augments post-exercise immune function in young males. Brain Behav Immun. 2012 Nov;26(8):1265-72.
Morgan N, Irwin MR, Chung M, Wang C. The effects of mind-body therapies on the immune system: meta-analysis. PLoS One. 2014 Jul 2;9(7):e100903
Nieman D, Wiedner T, Dick E. Exercise and the Common Cold. ACSM Current Comment. American College of Sports Medicine. http://www.acsm.org/docs/current-comments/exerciseandcommoncold.pdf?sfvrsn=4. Accessed 5th March 2015.