Does Exercise Boost the Immune System?

It’s no surprise that exercise is good for our health. Our bodies need to move to stay strong, flexible, and to keep our weight under control. But does exercise have any role in keeping the immune system healthy? As it turns out, exercise may be one of the best daily habits we can adopt to maintain strong muscles and strong immunity. 

How Does Exercise Boost the Immune System?

While many of us are familiar with the general benefits of exercise, there has been less concrete evidence on the effect of exercise on the immune system. More recent studies, however, conclude that regular exercise may substantially enhance our immune function and strength. 

Increased White Blood Cell Activity

From healthy aging to fighting infections, exercise supports our immunity. David Neiman of the Appalachian State University Human Performance Lab found that “Physically active people have a 40-50% reduction in the number of days they’re ill with acute respiratory infections.” Much of this effect is believed to be related to the increase in immune cell activity post exercise. 

Studies show that during and immediately after exercise, a higher concentration of immune cells (such as T- and B-lymphocytes, natural killer cells, and neutrophils) circulate in the blood. More research is underway to understand why immune cells are more active with exercise and what that means for our immunity. However, many speculate that this increased immune activity leads to earlier detection of invading pathogens and may prevent illness or infection.

Additional studies have shown that regular exercise can help improve immunity, especially in aging populations. A 2018 study showed that immunosenescence (the gradual decline in immunity with age) was reduced in active adults (aged 55 to 79) compared to a similar group who did not exercise. They also had markers for improved thymus health (increased recent thymic emigrants, high cytokine IL-7, and low IL-6), reduced inflammation, and a higher frequency of disease-fighting B-lymphocytes and T-cells. 

Increased Heat
During exercise, our body temperature rises. Some experts think this rise in temperature may help to stimulate the immune function and kill bacteria, similar to a fever. What studies have found so far is that the increased rise in body temperature does correlate with a more active immune response, especially in warm environments.

Reduced Stress
Stress, while helpful in acute situations, is known to weaken the immune system when chronic. Over time, elevated amounts of the stress hormone, cortisol, increases Type-2 cytokines which cause inflammation and the dysfunction of the immune cells. Exercise effectively releases stress-busting endorphins and reduces cortisol levels. With more balanced cortisol levels, inflammation calms and the immune cells can function properly. 

Exercise Recommendations for a Healthy Immune System

There may not be a perfect immune-enhancing exercise for everyone, but there is a way to find a perfect balance. It seems that a mix of weight-bearing exercise and cardio can best protect the immune system. While cardio helps to increase circulation throughout the body to achieve the benefits listed above (increased immune activity, heat, and reduced stress), weight-bearing exercises help to improve immune function through better bone health. 

Consistent, regular exercise offers the best immune support and defense against chronic disease. The Department of Health and Human Services recommend aiming for between 150-300 minutes of moderate activity per week, spread throughout the week in 20-60-minute sessions. 

As for intensity, low-impact, moderate exercise is most recommended. While vigorous exercise can help us achieve certain athletic goals, excessive or intense exercise can put unnecessary strain and stress on the body and work against our immune health. 

Whole Body Health Through Exercise

The research promisingly suggests that exercise is helpful for keeping our immune systems strong. When starting your exercise regimen, remember that the right type and amount of exercise varies person to person, and is based on your lifestyle, stamina, and any other health conditions. Speak with your doctor about the best plan for your unique health concerns.

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