We’ve finally reached the point where everyone in the U.S. who’s 16 and older is eligible for a COVID-19 vaccine. Although it’s clear the vaccines offer great protection against COVID-19, you still may have some questions about how they’ll affect your everyday life. Take working out, for instance: Maybe you’re wondering about exercise and the COVID-19 vaccines—and whether your exercise habits can influence your reaction to the shot.
There are three COVID-19 vaccines authorized for emergency use in the U.S., and all are effective at fighting COVID-19. (Moderna is 94% effective at preventing lab-confirmed COVID-19, Pfizer is 95%, and Johnson & Johnson is 66%—and all have even greater efficacy against serious disease or death. This doesn’t mean the Johnson & Johnson vaccine is automatically a terrible option. You can read more about why it’s difficult to directly compare these numbers here.) But like all medical treatments or drugs, they can come with some side effects. According to the Centers for Disease Control and Prevention, potential side effects of the vaccines include pain, redness, and swelling at the vaccine site, as well as systemic reactions such as fatigue, headache, muscle pain, chills, fever, and nausea.
Side effects aren’t the same for everyone across the board, though. Carl Fichtenbaum, M.D. an infectious disease specialist at the University of Cincinnati College of Medicine, tells SELF that individual reactions to the vaccine can be as disparate as a symphony is from a grunge festival, ranging from no reaction at all to being stuck in bed with flu-like symptoms for a few days as your body builds up protection to this dangerous virus.
These potential reactions are simply a byproduct of how vaccines work: Vaccines contain foreign substances called antigens specific to the infection you’re trying to prevent, Dr. Fichtenbaum explains. In an attempt to banish the antigen “invaders,” your immune system springs into action, releasing white blood cells and other tools. It’s this immune response that can make you feel a little icky in the hours or days following your vaccine.
Eventually your body will develop memory cells known as T-lymphocytes, a type of white blood cell that protects you from future infection. Say, for instance, you come in contact with SARS-CoV-2, the virus that causes COVID-19, after you’re fully vaccinated: Thanks to the vaccine, those memory cells should mobilize at the first sign of infection and quickly produce antibodies to fight the virus.
But what does this whole process mean for your exercise routine? Can working out impact this all-important vaccination? And then, what about what comes after? Here’s what you need to know about exercising and your COVID-19 vaccination.
1. Moderate exercise shouldn’t harm your vaccine response—and experts are even looking into whether it may help it.
While there are no actual quick “immune boosters,” moderate exercise does help your immune system function properly, as SELF has reported previously. So it’s only logical that scientists have wondered how an exercise session affects vaccine response in general. Because the COVID-19 vaccines are so new, however, there’s not much data on how exercise may affect the immune response to those vaccines specifically—and even existing data on other vaccines is not exactly conclusive. Still, there’s also no data showing that moderate exercise hurts your immune response. (While the CDC doesn’t offer explicit guidance on exercise and the COVID-19 vaccines, they do state that medical exercise tolerance tests are fine before or after.)
The more pertinent question, then, is whether moderate exercise can help your immune response. There has been prior research on earlier vaccines that suggest a potential benefit to exercise. A 2014 review published in Brain, Behavior, and Immunity analyzed 20 studies (including a bunch that examined vaccines for conditions ranging from influenza to pneumonia to tetanus) and concluded that both chronic and acute exercise may boost vaccine effectiveness. And more recently, when a 2020 study from the same journal compared 45 elite athletes to 25 age-matched controls (who exercised no more than twice a week), it found that the athletes had a stronger immune response to their influenza vaccine.
But if your workout motivation has waned during the pandemic—whose hasn’t?—don’t stress. The authors of a 2021 paper in Brain, Behavior, and Immunity exploring exercise’s effect on vaccine efficacy stated that, as we mentioned before, not only is the current data inconclusive, but much of it may not be applicable to the COVID-19 vaccine. There are still too many unknowns with this still-novel virus.
According to Hilary Babcock, M.D., MPH, an infectious disease specialist with BJC HealthCare and Washington University School of Medicine, the relationship between exercise and vaccination effectiveness is not necessarily causal. That means it might not be the exercise causing the improved response. Instead, it may be that younger, healthier people—who are more likely to have a good immune response to vaccines in general—may also be more likely to exercise, Dr. Babcock tells SELF.
Besides, while some research suggests a potential benefit, it’s also important to recognize that not exercising regularly didn’t show any harm to the immune response. After all, in the 2020 study mentioned above, even the control group showed a robust immune response to the vaccine.
So there’s no need to push yourself into exercise you don’t want to do in the hopes that you’re improving your immune system response for the shot. In fact, in a nod to your upcoming vaccine, it might actually be helpful to ease up a little before getting vaccinated.
2. You may want to go easier in your workouts prior to your vaccine.
Because it’s hard to predict whether or how intensely you’ll experience side effects, you may want to dial back the intensity of your workouts during the 48-hour period before you get your shot, Nanci Guest, Ph.D., R.D., CSCS, a certified personal trainer and athletic performance coach in Toronto, tells SELF—and definitely don’t make your early-morning workout the time you decide to try something new if your appointment is scheduled for that afternoon.
So if you typically go for a brisk 30-minute walk, don’t try a new bootcamp class; if you’re training for a half-marathon, trade hill repeats for an easy run. That’s because trying new workouts, or exercising more intensely than usual, can lead to delayed-onset muscle soreness, or DOMS. (So can eccentric-based training, which is a focus on the lowering portion of an exercise, where the muscle is lengthened under load, as SELF reported previously.) This soreness can make you feel worse if it’s compounded by flu-like side effects from the COVID-19 vaccine, says Dr. Fichtenbaum.
You may also want to switch some workouts around, too. If you know you have an upper-body strength-training routine planned for the evening before your vaccine—even if it’s one you’ve done before—you may want to swap it for a lower-body day. That’s because pain at the injection site (your upper arm) is the most common side effect of COVID-19 vaccine shots—83% of first-dose Pfizer participants reported experiencing it, according to the CDC. Couple that with routine DOMS, and you may feel extra uncomfortable after. (It’s important to remember, though, that these side effects are fleeting—but your COVID-19 protection will last for much longer!)
3. Gentle movement after your shot may help ward off soreness.
The CDC recommends you “use or exercise your arm” to minimize post-vaccine soreness. Unfortunately, there’s no real research out there on specific frequency, duration, or type of exercise to help you feel better, but Dr. Babcock does advise moving your arm more than usual.
This movement can involve upper-body strength training, as long as it isn’t making your pain any worse. A light workout for your arms and shoulders can help get your blood circulating, which may help arm soreness, says Dr. Fichtenbaum. (Just make sure you’re using an amount of weight that’s not causing you more discomfort—it may be significantly less than what you’re used to lifting, and that’s totally okay!) What it doesn’t include? Going for a P.R. on strength-training moves like shoulder presses, lateral raises, or dips—targeting your deltoids or triceps in particular with too much weight can exacerbate discomfort from the shot, says Dr. Fichtenbaum.
If you’re way too uncomfortable to even think about picking up a dumbbell or trying a push-up, intermittent, gentle arm movements can help with pain and swelling by stimulating blood flow. Dr. Fichtenbaum suggests shoulder circles, flexing and extending your elbow, or even gently rubbing your arm. Also, try to keep using your arm as you normally would, which can promote circulation. While this likely won’t prevent soreness, it might make it a little more manageable—which can be good news for your future workouts.
4. Easy workouts afterward may be key.
Plan for easy workouts during the 48 hours after your vaccination, even if you think you feel fine, says Guest. Same reasoning applies here as with workouts prior to your vaccine: You don’t want to trigger any kind of reactions, like muscle soreness, that can compound any possible side effects that may develop after your vaccine. After all, many of these can appear up to three days after receiving your shot, so while you may feel fine at first—and ready to work out—some effects may rear up after that may make that not such a great idea.
This is especially true after your second shot of Pfizer or Moderna, which tends to trigger more flu-like symptoms than the first. Fatigue, low-grade fever, and muscle aches are more common after that second jab, says Dr. Babock. (There’s no evidence that working out afterward affects the vaccine’s effectiveness, but remember, your immune system is working after a vaccine and after a workout to repair your muscles, so it’s possible you’d also take longer to recover after exercising, too.)
If you don’t feel 100%, there’s no reason to push through a hard workout—or even to work out at all. If you’re really wiped out, give yourself a break.
If you’re worried about “losing” fitness by taking it easy after getting your shot, that can actually be a good sign you’re overdue for a rest day, says Dr. Guest. If you’re overly focused on never missing a workout—even if your body is telling you otherwise—you’re much more likely to be at risk for overtraining, she explains. (And no, you’re not going to “lose” your fitness by missing a workout, or even a week of workouts.) She suggests taking advantage of the opportunity to trade your HIIT class for a brisk walk, an easy run, stretching, or even catching up on phone calls or reading.
According to Garrett Stangel, M.A., a master trainer for the American Council on Exercise and a health and performance coach who owns Balance Fitness in Milwaukee, if you have a fever or “feel like you need to be horizontal,” take a total rest day.
5. Adjust your workout expectations for the week following your vaccine.
For the week following your vaccination, Dr. Guest suggests dialing back the intensity of your workouts by about 20% and reducing the volume (say, fewer reps, sets, or exercises overall if you’re strength training, or a slower pace or shorter duration if you’re running or doing cardio) according to how you’re feeling. If you’re preparing for a race or an event, the week after your vaccine is a great time to build in a deload week (i.e., an easier week where you reduce your volume or intensity in order to recover and come back stronger). “It’s really important to listen to your body, and let your body tell you what it feels like doing,” says Dr. Guest.
If you feel fine, there’s no reason to avoid your regular routine, including longer or more intense workouts. But it’s also important to remain flexible, and consider changing up your workouts if you feel good enough to get moving but are not quite up to your regular routine. For instance, if your arm still feels too sore for an upper body workout but you have the energy, Dr. Guest says running, cycling, walking, and core work are great options to get your blood flowing without exacerbating your arm pain. (Of course, if any workout is making your arm pain worse, back off the intensity or call it quits, she says.)
Regardless of which modality you choose in the week post-vaccine, it’s important to temper your expectations: Don’t be surprised if you can’t hold the pace or lift the weights you normally would. After your shot, “you probably won’t see a P.R. that week,” says Stangel. Don’t beat yourself about it; your body is working hard even if you can’t feel it.
6. You still need to take precautions at the gym after getting your vaccine.
You’re fully vaccinated two weeks after your second shot (or your only shot if you received the Johnson & Johnson vaccine). That doesn’t mean you should go back to business as usual—meaning, no mask—at your gym or yoga studio even if the location does not require a face covering.
“You still need to wear a mask and take precautions,” Saskia Popescu, Ph.D., MPH, an infectious disease epidemiologist and assistant professor at George Mason University, tells SELF. In other words, you can develop COVID-19 without even knowing you have it. Plus, while getting the vaccine offers significant protection, it can’t guarantee with 100% certainty that you won’t catch or spread COVID-19 if you are exposed.
So when you’re exercising in public, whether it’s in the gym or at your yoga studio, the CDC guidelines we’ve been following since last year still apply. Dr. Popescu reminds people to focus on staying six feet apart whenever possible (ideally farther if you’re breathing hard), masking, hand washing, cleaning and disinfecting surfaces and equipment, and being especially cautious in indoor spaces with poor ventilation. “It’s not just one thing,” she explains. “Risk reduction is very additive.” No single precaution on its own works as well as taking multiple precautions together.
As for outdoor exercise? The CDC now says fully vaccinated people can now safely spend time outdoors in uncrowded outdoor settings with others without a mask, whether or not the others are vaccinated. If you’re not fully vaccinated, though, it’s a good idea to keep your mask handy for times when your regular trails or other workout spaces get too crowded to keep that proper distance.
And important note: Whether or not you’re fully vaccinated, if you feel under the weather, you should avoid exercising in public spaces, says Dr. Popescu. While you obviously don’t want to spread illness (whether it’s COVID-19 or just a cold), showing up at the gym with the sniffles can also spike anxiety among the people around you. That’s why Dr. Popescu suggests staying home even if you know your sniffles are just seasonal allergies. “Be mindful that this is a stressful time for everybody,” she says. “We’re living in a pandemic, and it does make people uncomfortable.”
Avoiding public gyms while you’re coughing or sniffling is one thing we hope continues as the pandemic begins to (hopefully) wane. Otherwise, we’re looking forward to the normalcy a session at the gym can bring—all made possible by that all-important vaccination, of course.