The COVID-19 vaccines rolled out a year ago, but the pandemic rages on. Over 790,000 people have died from coronavirus in the United States as of early December 2021. While the situation remains dire—the delta and omicron variants have both been reported in the U.S.—vaccinations are proven to slow the spread.

According to the Centers for Disease Control and Prevention (CDC), nearly 200 million Americans are fully vaccinated. That means they received either both doses of the Pfizer and Moderna vaccines or the single Johnson & Johnson dose. But if it has been at least six months since you were vaccinated, your immunity is receding. It’s time to get a COVID-19 vaccine booster shot.

For the latest vaccine information and recommendations, check the CDC website often. But since you likely won’t find any running-related answers there, we turned to three experts—all medical professionals and runners—to help fill in the gaps. Keep in mind that the virus and vaccine are both evolving situations, and that the information offered below is meant to supplement rather than replace personal advice from your physician.

What Symptoms Can I Expect From the Vaccine and Booster?

As with any shot, reactions to the COVID vaccines vary from one person to the next. Christine Firth, M.D., an internal medicine specialist in Phoenix, says that symptoms are generally not severe, and that some people don’t experience any. Firth says common side effects include pain and/or achiness at the injection site (possibly more severe than that of the influenza vaccine), general malaise/fatigue, body aches, headache, chills, fever, and joint pains. Depending on the person, these can last anywhere from a few hours to several days.

These fact sheets from Pfizer and Moderna, a version of which you should receive at your vaccination appointment, offer details on side effects and more.

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How Might Symptoms Differ Between the First, Second, and Booster Shots?

Though best known in the running world for her sixth-place finish in the 2019 World Championship marathon, Roberta Groner is also a registered nurse in Pittsburgh. She posted a photo of her second vaccine last month and reported no major side effects from either dose, but slightly different experiences: a sore arm and slight nausea for half a day after the first, and chills that lasted a few hours after the second.

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According to Kara Calhoun, M.D., a pulmonary/critical care fellow with a masters of public health in Denver, Groner’s experience isn’t uncommon. “The second round has been worse for a lot of people,” she says—though not for everyone. That goes for both the Pfizer and Moderna vaccines. While Calhoun had minimal symptoms after both doses, Firth had a sore arm after the first dose and a relatively sorer arm after the second. She also experienced mild fatigue, light-headedness, and nausea. Whatever you experience afterward, Calhoun emphasizes that the “degree of symptoms does not relate to the efficacy of the vaccine.”

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The CDC notes that the post-booster shot symptoms are similar to the regular doses. You also don’t have to get the same booster shot as your original vaccine; the CDC says mixing and matching is totally fine.

How Soon After Receiving a Vaccination or Booster Can I Run?

It’s unlikely that running right before or after receiving the vaccine or booster will impact how well it works. Firth and Calhoun encourage common sense by listening to your body and being flexible with your training until your body gives you the green light to proceed.

Firth completed her standard run the day of her first vaccine. (She ran after receiving it.) She took a gentler approach after the second dose, riding a stationary bike instead of running on the two days afterward. Calhoun biked the same day of her vaccine without issue, and Groner ran a tempo workout the morning after each dose.

As far as upper-body work, Calhoun actually encourages it post-vaccination. It may seem counterintuitive to tax a sore arm, but, Calhoun says, working out can sometimes help with muscle stiffness. If your soreness is severe, if you’re generally feeling unwell, or if you aren’t used to strength training, it would be wise to push a lift back until your symptoms subside.

If I Have an Underlying Medical Condition, Should My Vaccination Approach Change?

If you have an underlying medical condition such as cancer, obesity, or a heart condition, it’s totally safe—and highly recommended—you get the vaccine. According to Firth, “Many medical conditions place you at higher risk for a severe COVID-19 infection, so vaccination is recommended to those who are eligible.”

She adds that speaking with your physician and the vaccination provider in advance is an especially good idea if you are “immunocompromised from a medical condition or medications, have a history of immediate allergic reaction to a prior vaccine or injectable therapy, or currently experiencing a moderate to severe illness.” Pregnant women, while considered a high-risk demographic, have been recommended for vaccination by the American College of Obstetricians and Gynecologists.

The one exception is any individual who has had a severe reaction to any ingredient in the vaccine or booster, such as polyethylene glycol (PEG) or polysorbate. If that’s you, or if you have questions about other allergies, find CDC recommendations here and ask your doctor to help you formulate an alternative approach.

Are There Any Downsides a Runner Should Consider Before Getting a Vaccination or Booster?

In short: no. Firth, Calhoun, and Groner all echoed some version of the sentiment that feeling crummy for a day or two far outweighs the possibility of getting or spreading the virus.

Firth calls the vaccines extremely effective, with 95 percent efficacy after the second dose, as well as “the most promising approach for controlling the pandemic.” She signed up when it first became available, with her patients, family, community, and personal health in mind.

Calhoun chimes in from a runner’s perspective, adding that COVID “could really devastate a season” or prevent someone from training normally for a significant amount of time. Shortness of breath lasting months is not unheard of, no matter how fit a person is when infected. And according to Calhoun, as of now we don’t have a solution for that, nor do we understand the long-term effects of the virus.

Groner agrees, saying, “You may feel ill for one day, but honestly, that’s better than contracting COVID and potentially spreading it to loved ones. I hope that all in the running community will play their part in building a safer and healthier future by vaccinating.”

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Becky Wade
Contributing Writer

Becky Wade is a three-time Olympic Trials competitor with a 2:30 marathon best. Her book about global running cultures, Run the World, was published in 2016.