Winter brings with it the party season. And of course it also brings colder temperatures and an increased risk of colds and flu. Add that to lower vitamin D and a generally higher rate of alcohol consumption, and we can seriously weaken our immune systems. But, fortunately for us there are a few different things that we can do to help strengthen our immune systems during the winter months. And of course, today we’ll be talking about one of those methods and that is of course exercise.
The question of course is, how much exercise is optimal to boost immune health?
Exercise and Immunity
It’s been known for quite some time that moderately intense exercise has been shown to have a positive impact on immune system health.
It’s been proven to help lower levels of chronic inflammation and improve the body’s ability to fight off a lot of different types of infections.  Regular exercise has also been shown to improve “immune surveillance” which makes it easier for your body to detect and eliminate potential threats .
Finding the Right Exercise Prescription
The minimum recommended amount of exercise is 20-30 minutes of moderate intensity exercise five times per week. This aligns with the American Heart Association's guidelines for optimizing heart health and reducing the risk of chronic diseases .
How to Determine Moderate Intensity
Of course, understanding what moderate exercise actually means can be a little bit tricky. There are few different ways to determine if you're exercising at a moderate intensity:
Track Your Heart Rate: Aim to reach 60-75% of your age-predicted maximum heart rate (220 minus your age) during exercise.
Use the RPE Scale: Rate your perceived exertion on a scale of 1-10, with 5 or 6 indicating a moderate level of intensity, although this is generally not a very effective measure as it's completely subjective.
Walk and Talk: During exercise, you should be slightly breathless but still able to hold a conversation with a friend. Avoid going completely breathless.
It's important to note that while high intensity interval training does have it’s own benefits, if you’re looking to boost your immunity then it's best to stick to moderate intensity workouts.
Does Strength Training Boost Immunity?
The answer is yes, strength training is not only beneficial for building muscle and improving overall fitness but it can also dramatically improve immune cell function.
Studies have shown that just one session of strength training can make improvements to your immune system boosting immune cell circulation and function .
Consistent strength training has long-term effects on the immune system, reducing inflammation levels and strengthening immune response.
To maximise the effects you should aim for at least 2-3 sessions of strength training per week to further enhance your immune health.
Rest and Recovery: The Flip Side of Exercise
While exercise can significantly boost immune health overtraining can have the opposite effect. Engaging in prolonged high-intensity exercise without adequate rest can (temporarily) harm the immune system.
If you're involved in activities such as marathon running or HIIT workouts it is important to properly schedule rest days and get enough sleep.
Exercising When You're Sick
While exercise is generally good for your immune system there are of course a few caveats.
If you're sick and your body is already working hard to fight off an infection, it's important to prioritize rest and allow your immune system to recover.
If your symptoms are "above the neck" (such as a runny nose or mild headache) light to moderate exercise is probably fine, and the improved blood circulation can offer temporary relief to some symptoms such as a blocked nose. However, if your symptoms are "below the neck" (such as a cough or chest congestion), it's generally best to skip your workouts until you're feeling better. Light exercise is still often OK, but you don’t want to train particularly hard. It’s important to listen to your body.
So Does Exercise Improve The Immune System?
When it comes to boosting your immune system in winter exercise is a powerful tool. Whilst many of us get less exercise at this time of year, if you manage to keep up to a good fitness routine you can largely reduce the time you spend ill over the holiday season.
While illness is a normal part of life exercise can be a preventative measure to strengthen your body and its systems. By engaging in regular physical activity, you can enhance your immune system, reduce the risk of chronic diseases, and improve overall health.
1 - Chen, L., Deng, H., Cui, H., Fang, J., Zuo, Z., Deng, J., Li, Y., Wang, X., & Zhao, L. (2017). Inflammatory responses and inflammation-associated diseases in organs. Oncotarget, 9(6), 7204–7218
2 - Kopecky, S. (n.d.). Understanding immune system health - Mayo Clinic. Mayo Clinic
3 - American Heart Association recommendations for physical activity in adults and kids
4 - Fortunato, A. K., Pontes, W. M., De Souza, D. M., Prazeres, J. S., Marcucci-Barbosa, L. S., Santos, J. M., Veira, É. L., Bearzoti, E., Pinto, K. M., Talvani, A., & Da Silva, A. N. (2018). Strength training session induces important changes on physiological, immunological, and inflammatory biomarkers. Journal of Immunology Research, 2018, 1–12