The benefits of regular exercise are seemingly endless. From reducing your risk of chronic conditions to clearing up your skin and boosting memory, physical activity is an essential tool for fighting and preventing disease.
The immune system is also very responsive to exercise. While researchers are still understanding how it stimulates your body’s immune response, the latest science suggests that exercise can boost your immune system and may even amplify your vaccine response.
So, how to get the most out of your daily workouts for overall and use fitness to your advantage, especially during the pandemic? Here’s what you need to know.
How exactly does exercise boost the immune system?
You already know that exercise keeps you fit and helps you look and feel great. But how? What is it about physical activity that’s so beneficial to your health? This is what happens to your body during exercise:
First, your temperature rises. Muscles need energy to perform effectively, so your body will start burning calories from the fats and carbohydrates that it has stored away from your meals. Within a few minutes of activity, you will start to feel your heart pounding harder and your breath getting shallower. Physical activity increases your heart rate to allow more blood to reach the muscles when they need it the most.
Your body will also release a series of chemicals called endorphins. Endorphins interact with neurotransmitters in your brain to block pain signals and trigger a positive feeling throughout the body. Also known as the “feel-good hormone,” endorphins are responsible for the so-called “runner’s high:” the temporary feelings of euphoria and relaxation that follow a long run.
Experts believe that the brief rise in temperature coupled with changes in hormone secretion may be at least partly responsible for exercise’s immune-boosting effects. Another theory is that the increase of blood flow during physical activity also boosts the circulation of immune cells.
A 2019 review of research studies published in the Journal of Sport and Health Sciences listed important exercise and immunology scientific discoveries since the 1980s, including:
- Moderate to high-intensity exercise stimulates the production of disease-fighting white blood cells, particularly killer T cells, neutrophils, and anti-inflammatory cytokines.
- Regular exercise has significant anti-inflammatory effects on the body. And there is evidence that chronic inflammation suppresses the immune system.
- Physical activity boosts the diversity of the gut microbiome. A robust microbiome has been associated with increased immune function.
- There is compelling evidence that moderate exercise can reduce the risk for upper respiratory tract infections. In fact, regular physical activity is associated with decreased incidence rates for pneumonia and the flu.
- Regular physical activity enhances vaccination response.
There isn’t much COVID-19 specific data to say whether physical activity can protect against the virus. However, adopting a healthier lifestyle, including exercising regularly, may reduce your risk of serious upper respiratory tract complications and could help you recover faster if you are exposed to infection.
What are the best exercises for immune health?
Research on specific immune-friendly exercises is still limited. Most studies have looked at aerobic activity – walking, jogging, swimming. The American Heart Association recommends a minimum of 30 minutes of aerobic or cardiovascular physical activity of moderate intensity five times a week.
Strength training, weightlifting, and high intensity training are also likely to boost your immune system. Just remember to pace yourself and stretch before and after working out to avoid injury.
Can too much exercise damage your immune system?
Your risk of catching a cold decreases with regular exercise, but some studies suggest that workout type and intensity could also influence its effects on your immune response. Meaning that more is not necessarily better.
There is no evidence that intense or lengthy training increases your chances of developing any kind of viral infection. An observational study of 11 elite runners and cross-country skiers found that high-performance athletes tended to report few annual sick days, suggesting that intense physical activity may have played a role in bolstering their immune system.
But pushing yourself too hard – especially if you are new to exercise – may temporarily impair your immune system. In a 2008 animal study of upper respiratory tract infections, mice that ran strenuously for a prolonged period and were exposed to the influenza virus developed more severe symptoms than mice that ran moderately. The differences were marginal, but exercise newbies might want to start slowly and build up gradually.
