A common question I hear is, does exercise reduce the risk of getting sick? In general, including physical activity as part of your daily routine is a great way to improve your overall health, but whether or not it will strengthen your immune system depends on 1) the intensity level of your exercise, 2) the frequency and 3) the duration of your effort.
The Canadian Physical Activities Guidelines recommend at least 150 minutes of moderate to vigorous intensity aerobic physical activity per week. With that said, there is a point where benefits subside and can actually reverse with prolonged activity and lack of recovery time. Long duration high intensity activities can be draining on our bodies. For those participating in prolonged high intensity activity, like an endurance athlete going out for a 3-hour run, this can actually lead to the suppression of their immune system. On top of aerobic exercise, it is recommended we perform activities that support bone-strength and use of our major muscle groups at least twice per week.
Exercise supports our immune system by:
- Clearing out bacteria from our respiratory system: Physical activity increases the amount of air exchanges taking place through our lungs and airways. Similar to improving air quality in a building, the more air exchanges that take place, the better. The quicker movement of air helps clear our lungs of germs likely reducing the chances of us catching a cold or flu.
- Temporarily increasing our body temperature: Raising our internal temperature helps kill off and prevent bacteria from growing. Similar to when we have a fever, temporarily increasing our body temperature helps kill germs, reducing the amount of bacteria in our body that may cause illness.
- Temporarily increasing our heart rate: This leads to our antibodies and white blood cells circulating throughout our body faster, allowing our body to respond more quickly to any pathogens recognized.
- Improving both the quality & quantity of sleep: Physical activity during the day leads to a better night’s rest which is associated with an improved immune response when compared to people who are sleep deprived.
- Providing relief from stress: Exercise has been found to be an effective way to decrease the release of stress hormones which is also associated with reducing the risk of illness.
- Reducing the risk of many other illnesses: Minimizing the risk of other illnesses including diabetes & heart disease, allows our immune system to be better able to fight off pathogens found. When our body is not required to deal with other illnesses at the same time, this not only reduces the likelihood of becoming ill but also the likely severity of illness.
I’ll suggest you take a moment to consider whether your current activity level is optimizing the strength of your immune system. If so, great, keep it up! If not, consider increasing your activity level, finding an activity you enjoy, one that gets your blood pumping, the airflow moving through you and reap the benefits! Ensure you are getting proper rest and recovery to improve your overall health and immunity!
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7387807/
https://medlineplus.gov/ency/article/007165.htm
https://www.healthline.com/nutrition/does-exercise-boost-immune-system#benefits-for-immunity