An article by Exercise Physiologist Jenifer Smallridge

It’s never been more important to nurture and enhance your immune system. Whilst we go about our daily lives, an army of cells and tissues work together to defend against seasonal threats, viruses and bacteria.

Along with good hygiene, sufficient nutrition, regular sleeping patterns and stress; regular exercise is a factor which can influence the strength of your immune system, keeping those bugs at bay. Read on to find out how.


Getting your gut health right
Just six weeks of exercise training (2.5 hours of physical activity per week - that’s just half an hour on 5 days of the week!) has been shown to increase something special in the gut known as SCFA: short chain fatty acids.

These amazing little helpers can work together to protect the gut barrier and contribute to your immune system. With cold and flu season fast approaching, think of regular exercise as your extra insurance against falling sick!


Killer workouts = killer cells
Everyone has superhero cells inside them known as natural killer cells, and when activated, they work to kill viruses and suppress tumour formation in the body. Research has shown that embarking on an exercise program wakes these killer cells up, ready for battle. How cool is that?

There is some truth to ‘too much of a good thing’ here: just be mindful that workouts going for longer than an hour can start to slightly suppress the immune system, making us a little more vulnerable to infection. A great reason to reach for the oranges if you play winter sport! It is worth noting that this impact on the immune system is the same as a disrupted night’s sleep, highlighting the importance of good recovery.


Braving the cold
Layering up is super important if you’re going to face the elements–warm gloves, socks and a beanie can all keep the heat in –but remember that your body has its own thermostat and if you start exercising, your core temperature will rise!

Contracting muscles get the blood flowing and give off heat as a by-product of their metabolic processes – a total winter win-win for active bodies. David Nieman, lead researcher from Appalachian State University in the US found that in one study, people who went for a brisk walk several times per week reduced their sick days by 40%. Bonus points if you can get out in the sunlight and naturally boost your Vitamin D, which is essential for immunity and a good mood, something we all could all use right now.



Mailing, L.J., Allen, J.M., Buford, T.W., Fields, C.J. and Woods, J.A., 2019. Exercise and the gut microbiome: a review of the evidence, potential mechanisms, and implications for human health.Exercise and sport sciences reviews,47(2), pp.75-85

Nielsen, H.G., 2013. Exercise and immunity.Current Issues in Sports and Exercise Medicine, pp.121-140

Nieman, D.C. and Pedersen, B.K. eds., 2000.Nutrition and exercise immunology.CRC Press.

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