Here’s what doctors say about the results of a new study related to vaccines.
Exercise has a wide variety of health benefits beyond staying in shape, and one of the main ones is boosting immunity. And as it turns out, according to a new study, exercising regularly could boost the benefits of your COVID-19 vaccine.
Researchers examined 200,000 men and women in South Africa, collecting data regarding vaccinations, COVID outcomes and exercise routines. They found COVID vaccination was effective in protecting them against serious infection. However, it was most effective in those who exercised on a frequent basis.
How Exercise Can Help With the Effectiveness of the COVID Vaccine
As shown by the study, those who received the Johnson & Johnson COVID vaccine (Ad26.COV2.S) and exercised at a high level were almost 3 times less likely to be hospitalized for COVID than people who were vaccinated but had only low levels of exercise, Dr. William Li, internationally renowned medical doctor, researcher, Angiogenesis Foundation President/Founder and author of Eat To Beat Disease, explains. This study was unique because it looked at a hard endpoint of hospitalization and also documented exercise by wearables.
Researchers have known for some time that exercise stimulates the immune system and can jack up the immune response to a vaccine by creating more protective antibodies in the blood. Exercise also activates immune T cells that destroy viruses, and it also improves the layer of immune defenses lining the nasal passages where respiratory viruses enter the body, Dr. Li states.
Regular exercise also promotes better sleep at night, and sleep quality is also important for immune response.
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An additional point: Those who take the time to exercise, especially those who do high-intensity exercise, are more likely to take better overall care of their health, including choosing a healthier diet and lifestyle. Dietary choices, specifically eating more whole plant-based foods such as blueberries, tree nuts and omega-3-rich seafood have been shown to enhance immunity, Dr. Li adds.
“We have limited data on the effect of exercise on COVID vaccine efficacy,” says Dr. F. Perry Wilson, MD, of Yale Medicine. “But we know that exercise on its own appears to be quite protective against bad COVID outcomes. People who frequently exercise are markedly less likely to be hospitalized due to COVID or to die due to COVID complications.”
The BMJ study gives us the best data yet to suggest that exercise has a direct effect on the immune response to vaccination, showing that vaccine efficacy is higher among those who exercise more.
This is a really subtle but important point. It wouldn’t be surprising that sedentary individuals had worse COVID outcomes—that has been shown in multiple prior studies. But the vaccine should still work in that group, Dr. Wilson adds. And indeed it does, reducing the rate of hospitalization by about 60%. But what’s striking is that it works better in the more active group—a group who, overall, is less likely to be hospitalized.
Exercise is a complex physiologic state—it raises your heart rate, dilates certain blood vessels (and constricts others), and increases the levels of certain hormones (and decreases others), so the pathways by which exercise can influence the immune system are numerous, Dr. Wilson explains. But it’s no surprise that the overall effect is good: Exercise is one of the best things you can do for your body, and it is likely pretty good for your immune system as well.
“There are likely many reasons why exercise can make COVID vaccinations more effective,” says Justen Elbayar, MD, an orthopedic surgeon in the department of Orthopedic Surgery at NYU Langone Huntington Medical Group. “As per the study, ‘physical activity has been shown to have effects at many levels, including the organelle level, allowing for individuals to have a ‘combination of enhanced antibody levels, improve T cell immunity surveillance and psychosocial factors. This suggests that exercise encourages your body to prepare a more robust immune response, thus making the vaccinations more effective,”
The Dangers of a Sedentary Lifestyle
The study also showed that the vaccinated group who exercised for a minimum of 1 hour each week, were 1.4 times less likely to be hospitalized compared to the sedentary and vaccinated participants. This indicates that vaccines were about 12 percent more effective in those who exercised compared to those who didn’t.
“Sedentary lifestyles are associated with overall weaker health defenses, including immunity. This is one explanation for the lower effectiveness of vaccination preventing hospitalization,” says Dr. Li. “People who live a sedentary lifestyle also often make poorer dietary choices, which can influence the gut microbiome and thus, increase inflammation and lower immune responses. Having even a little exercise can counter these effects.”
Related: Weekend Warriors May Reap the Same Benefits As Daily Exercisers, According to New Research
Even brief bouts of exercise can change the chemicals in your blood—hormones, cytokines and chemokines—and alter your sugar metabolism among multiple other effects, Dr. Wilson states. How those bouts interact with the immune system is still unclear, but it does appear that something is happening to boost the production of immune molecules like antibodies when you’re exercising.
“One of the most important effects of exercise is improvement in how our body heals and copes with injuries and illness,” says Dr. Elbayer. “Why vaccines may be more effective in those who exercise is likely multifactorial. A more robust immune response to the vaccines plays a huge role.”
The Amount of Exercise You Need per Week To Reap the Benefits
The BMJ study showed there was a dose-response to the effectiveness of the COVID vaccine for preventing hospitalization. The people who had the most benefit exercised for at least 150 minutes per week at a level that raised their heart rate to between 70-80% of maximum, Dr. Li explains.
But even moderate exercise, which was defined as 60 minutes to 149 minutes per week, was beneficial for lowering the risk of hospitalization.
The bottom line: when it comes to benefitting from the Johnson & Johnson COVID vaccines in this study, some exercise was better than none, and the more people exercised, the more protection they received. This shows that there are steps people can take to enhance the effectiveness of other vaccines too, Dr. Li adds.
“The BMJ study suggests that there is a dose-response relationship here. That means that even minimal exercise might lead to some benefit, with more exercise leading to more benefit, says Dr. Wilson. “My advice reading this study is what I tell my patients all the time—do whatever exercise you can, and when you can do that comfortably, try to do a bit more.”
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