Exercise & the Immune System

Exercise, a Key Element to Robust Immune System

walking in the parkResearchers have repeatedly found that regular exercise improves health and immunity.  They see reduced risk of cardiovascular, respiratory, and digestive problems, vision conditions, weight management issues, hormonal imbalances, and those who get regular moderate exercise have stronger immune system.  Depending on our personal likes and dislikes, this exercise can be moderate or intense, but regular modest exercise has been shown again and again to have a beneficial effect on the immune system.

The balance between duration and intensity of such exercise is a factor in the resulting effect on the immune system. “Exercise has a profound effect on the normal functioning of the immune system. It is generally accepted that prolonged periods of intensive exercise training can depress immunity, while regular moderate intensity exercise is beneficial.”1

How much exercise?

Moderate exercise – for example, a daily brisk 20-30 minute walk, dancing, aerobics, yoga that gets your heart pumping a bit – anything that gets your heart rate up.  This means that you achieve 55% to 85% of your maximum heart rate (MHR) for at least 20 to 30 minutes.

Calculating MHR.

You can calculate MHR as 220 minus your age to be the upper limit and you want 55-85% of that number.

For example a 60 year old’s MHR would be 160; 55% of 160 is 88 and 85% of 160 is 136.  So a 60 year-old’s target would be 88 to 136 beats per minute.  A 40 year-old’s target would be 99 to 153 beats per minute. The talk test is an easy way to judge your HR.  If you can talk but can’t sing you are getting moderate exercise; if you can’t talk you are getting too much exercise; and if you can sing while you exercise you are not doing it briskly enough.2

Exercise and your immune system

Moderate-intensity exercise is considered “immuno-enhancing,” and may result from lowered inflammation, immune cell integrity, the ability of the immune system to look for and recognize unfriendly visitors, and relief of psychological stress.3  This immuno-enhancing exercise also effectively improves vaccine responses in otherwise at-risk patients.4

This is not so true of isolated single instances of moderate exercise. In fact isolated bouts of vigorous exercise have a detrimental effect on immunity, while regular, frequent exercise delays aging of the immune system.5

There has not been a lot of research about exercise and viruses.  In patients with human immunodeficiency virus (HIV) routine physical activity is helpful.6  Patients with herpes-type immunodeficiency, and their response to vaccination, also may benefit from regular exercise.7

Update: COVID-19

While we’re confined to our home during the 2020 COVID-19 pandemic it’s tempting to enjoy snacks and all those great movies we’ve missed.  However, exercise is even more essential now.  It is the regular, every day, moderate exercise such as a good, brisk walk, or even a lot jog (not a strenuous run) that stimulates our immune system, cardiovascular system, respiratory system, and actually, every other part of your body including visual system and the brain.

So get outside, or if you can’t go outside, perform exercise inside your home: dance, do yoga, martial arts, pilates, or anything else that gets your heart rate up to that 55-85% of your MHR.  If you have internet access there is a huge variety of workout routines online which you can vary to protect yourself from boredom, and if you don’t have internet access, then dance!

  1. Simpson RJ, Kunz H, Agha N, Graff R. (2015). Exercise and the Regulation of Immune Functions. Prog Mol Biol Transl Sci. 2015;135:355-80.
  2. www.cardiosmart.org
  3. Ibid. Simpson. (2015).
  4. Ibid. Simpson. (2015).
  5. Campbell JP, Turner JE. (2018). Debunking the Myth of Exercise-Induced Immune Suppression: Redefining the Impact of Exercise on Immunological Health Across the Lifespan. Front Immunol. Apr 16;9:648.
  6. Jaggers JR. (2018). Exercise and Positive Living in Human Immunodeficiency Virus/AIDS. Nurs Clin North Am. Mar;53(1):1-11.
  7. Simpson RJ, Bigley AB, Spielmann G, LaVoy EC, Kunz H, Bollard CM. (2016). Human cytomegalovirus infection and the immune reponse to exercise. Exerc Immunol Rev. 2016;22:8-27.