This article is the fifth installment in a 5-part series on boosting immunity and resilience, created by Brent Bauer, MD, Director of Research, Integrative Medicine Program at Mayo Clinic.
How Exercise Benefits the Immune System
A recent survey found that almost half of U.S. adults believe the COVID-19 pandemic is harming their mental health.1 This is an alarming statistic when you consider that decades of research show that stress triggers or aggravates a wide range of health problems and compromises your immune system.2
Fortunately, you can turn to a highly effective and research-backed strategy to help offset the effects of stress and boost immunity: physical activity.
Individuals of any age, physical ability, and health status can benefit from regular movement. And you don’t have to exercise for an hour every day to reap the benefits.
Physical Activity Creates Same-day and Long-term Benefits
In response to just one session of exercise, billions of white blood cells (lymphocytes) are rapidly circulated throughout your body. This can allow these white blood cells to detect and fight illnesses sooner.3 In addition, one exercise session that elevates your heart rate has been shown to lower blood pressure, improve sleep, and lower anxiety on the same day you do it.4
Many studies have found that exercise protects against viral infections, including influenza and the rhinovirus, a cause of the common cold.5,6 In addition, exercising at moderate-to-vigorous intensity can improve immune responses to vaccinations and reduce chronic low-grade inflammation.5 During moderate activity, you breathe hard and can converse, but you can’t sing. Vigorous means you can’t say more than a couple of words without taking a breath.
Research also shows that other benefits – like a lower risk of many chronic diseases – start adding up within days or weeks of regular physical activity.4 In fact, multiple studies indicate that regular exercise improves immune markers for HIV, cancer, cardiovascular disease, and diabetes.4-6
Keep in mind that if you already exercise, then you shouldn't exercise more to increase immunity. Repeated and strenuous physical activity can actually suppress immune function.3,7 You don't need to suffer from exercising to reap its benefits.
How Much Exercise Do You Really Need?
Every 10 years, the U.S. Department of Health and Human Services establishes Physical Activity Guidelines for Americans. An independent scientific panel gathers evidence to create the recommendations for exercise. The guidelines, updated in 2018, explain why and how you feel better with regular movement. Follow these evidence-based recommendations to make sure you get enough exercise.4
- Sit less and move more. Individuals who sit less and get even small amounts of moderate or vigorous physical activity gain some health benefits.
- For big health benefits, aim for these numbers: 150-300 minutes (2.5-5 hours) of moderate aerobic activity or 75-150 minutes of vigorous aerobic activity weekly spread throughout the week.
- Strength train at least twice weekly. Your bones, joints, and muscles help you climb stairs, carry kids around, and more, so work your major muscle groups weekly.
- If you can’t meet these guidelines, then be flexible. Older adults and individuals with a health condition or a disability should aim to meet the recommendations. But if you don’t meet them all the time, that’s okay. Get regular activity as you’re able and avoid being inactive.
Add the Right Amount and Types of Movement into Your Life
The key to making exercise a habit is to find activities you like that fit your lifestyle.
- Find what motivates you. If the goal of lowering your long-term risk of disease isn’t getting you out the door, don't worry. Most people stick with a good habit because of the everyday benefits. Notice what motivates you: Better sleep, lower stress levels, being outdoors, or working out with a friend are all good ideas.
- Multi-task. Incorporate movement into your regular activities. Binge-watching a favorite show? Stretch, do sit-ups or jumping jacks, or other activities between episodes or during commercials. Mix up your family-time routine and shoot some hoops or walk the neighborhood. Instead of jumping behind the wheel, hop on your bike or walk to work or the grocery store.
- Don’t discount the little things. All activity counts, even if it’s five minutes. It all adds up. Virtually any form of exercise or movement can increase your fitness level. The most important thing is to pick an activity you enjoy.
- Look online. During this pandemic, many organizations are offering online courses you can join. Options run the gamut from yoga and tai chi to intense boot-camp workouts and spinning classes. There are also plenty of free exercise videos and instructions online. Here is just a small sampling for you to explore.
Short on Time?
Even brief bouts of activity are beneficial. If it works best for you, then exercise in increments. For instance, if you can't fit in one 30-minute walk, then do three 10-minute walks instead. Interval training, which entails brief (10-90 seconds) bursts of intense activity at almost full effort, is a safe, effective, and efficient way to gain many of the benefits of longer duration exercise. In fact, a particular form of exercise called high-intensity interval training (HIIT) has been shown to slow and reverse some age-related changes at the cellular level.8
The evidence keeps rolling in: exercise is an important approach to staying healthy. Plus, it helps improve your attitude and mental health. And that's the proverbial win-win. Brent Bauer, M.D.
An important note: No dietary supplement can diagnose, treat, cure or prevent any disease, including COVID-19. With the ongoing COVID-19 pandemic, it is especially important to understand that no dietary supplement, no diet, and no lifestyle modifications – other than the recommended social distancing and hygiene practices – can prevent you from being infected with the COVID-19 virus. No current research supports the use of any dietary supplement to protect you from being infected with the COVID-19 virus.
- Kaiser Family Foundation. KFF Health Tracking Poll – Early April 2020: The impact of coronavirus on life in America. Kirzinger A, Kearney A, Hamel L, Brodie M. https://www.kff.org/health-reform/report/kff-health-tracking-poll-early-april-2020/. [Accessed May 1, 2020]
- Simpson R, Kunz H, Agha N, Graff R. Exercise and the regulation of immune functions. Prog Mol Biol Sci 2015;135:355-380.
- National Institutes of Health. U.S. National Library of Medicine. https://medlineplus.gov/ency/article/007165.htm [Accessed May 5, 2020]
- Physical activity guidelines for Americans, 2nd edition. U.S. Department of Health and Human Services. https://health.gov/paguidelines/second-edition/pdf/Physical_Activity_Guidelines_2nd_edition.pdf. [Accessed May 1, 2020]
- Duggal N, Niemiro G, Harridge S, et al. Can physical activity ameliorate immune-senescence and thereby reduce age-related multi-morbidity? Nat Rev Immunol 2019;19:563-572.
- Martin S, Pence B, Woods J. Exercise and respiratory tract viral infections. Exerc Sport Sci Rev 2009;37:157-164.
- Jones A, Davison G. Exercise, immunity, and illness. Musc Exer Physiol 2019;317‐344.
- Robinson M, Dasari S, Konopk A, et al. Enhanced protein translation underlies improved metabolic and physical adaptations to different exercise training modes in young and old humans. Cell Metab 2017;25:581-592.