Running News Daily

New research finds a temporary decrease in a key aspect of fitness.

Everyone has that friend who got their COVID-19 vaccine and bounced back the next day, with little more than a sore arm. We’ve also heard (or told) stories of being in bed for multiple days after the first, second, third, and fourth shot. 

While no one enjoys feeling unwell, runners have an added concern: How will a shot affect my upcoming training and racing?

A recent study offers some quantification to anecdotal evidence runners have been sharing for the past year and a half, where the new research found a small decline in aerobic capacity post-booster. Here’s how to incorporate that finding into your training plans.

Why Runners Care About VO2 Max

VO2max is often treated as the gold standard measurement of cardiovascular fitness. It represents the maximum amount of oxygen your body can use during exercise. This matters for runners because, all else equal, the more oxygen you can use, the harder you can work.

Given the significance of VO2 max to athletes, researchers in Belgium set out to test whether the COVID-19 booster affected it. They recruited 42 recreational endurance athletes (runners, cyclists, and swimmers) who were scheduled to receive their COVID booster—i.e., the third shot in the two-series Pfizer vaccine. Just before they got their shot, the athletes took a VO2 max test. This involved riding a stationary bike while wearing a device that measured oxygen consumption. As resistance on the bike went up, their oxygen consumption also went up until it eventually plateaued—indicating VO2max.

One week after receiving their booster, the athletes repeated the test. Compared to their performance pre-booster, their VO2max showed, on average, a 2.7 percent decrease.

Given that a decline in VO2 max reflects a decline in cardiovascular fitness, this finding is worth factoring into your training and racing plans. However, it’s worth noting that a 2.7 percent decrease in VO2 max does not necessarily mean a 2.7 percent decrease in speed. Here’s an example using Jack Daniels’s VDOT values (which are a proxy for VO2 max).

Let’s say a runner with a VDOT of 38 gets her COVID booster. This lowers her VO2 max (VDOT) by 2.7 percent, giving her a reduced VDOT value of 36.97. According to Daniels’s calculations, all else being equal, her previous 5K time of 25:12 would slow to about 25:45, or by 33 seconds—which is only 2.2 percent slower. If she’s fitter and has a half marathon time of 1:44:20 and a VDOT of 43? One week after the booster, her VDOT would be just below 42, and her half marathon time would increase from 1:44:20 to around 1:46:30, or by 2.1 percent.

VO2 Max Isn’t Everything

Admittedly, these calculations assume “all else being equal,” which is virtually impossible. Many other factors contribute to running performance, including running economy (how much oxygen you need to run a given pace), stride mechanics, and even perceived effort. Hielko Miljoen, a sports cardiologist at University of Antwerp and lead author on the paper, pointed out that in that respect, this study is only the beginning of an answer to how the booster affects performance.

“The next step in this investigation should be to do an endurance test, because VO2max is just one part of exercise capacity and athlete performance,” he says. 

Additionally, the researchers only tested VO2 max one week out from the booster shot. While it’s unknown what effects may exist further out from the shot—the researchers did not retest the athletes at later intervals—it seems unlikely that the decline is permanent. “This study is by no means an answer,” says Miljoen. “It is trying to reassure people that the effects are not huge, probably not lasting.”

Weigh the Risks

Every medical decision is a personal one, and the reality is that getting the COVID-19 vaccine, including the booster, doesn’t come with a non-zero amount of risk.

“The entire field of medicine comes with statistics,” says Miljoen. “The benefit and harm of a certain medical procedure or intervention are only known on a population basis, so individuals must make up their own mind based on the data out there.”

While life-threatening risks of the vaccine are low, getting it or the booster may interrupt your training for a few days. A recent study of more than 1,000 elite Polish athletes found that the athletes lost an average of two and a half training days around getting the COVID vaccine. However, the same study found that athletes lost an average of eight training days due to COVID-19 infection. Given these and other research data, the authors concluded in favor of vaccination for athletes, writing that “the benefit–loss ratio strongly favors vaccination.”

Time Your Shot Strategically

While it doesn’t feel great to miss any amount of training, one advantage of vaccination and booster shots is that they can be timed to have minimal impact on a racing season—whereas COVID infection can’t.

Ben Rosario, executive director of Hoka NAZ Elite, recalls two of his athletes contracting what he believes was COVID in January 2020.

“I think it really affected them in the 2020 Olympic Trials marathon, because it was a real detriment to their training at that time,” he says. “They missed a really important 10 or so days of training.”

With the initial vaccines, he observed that athletes would feel unwell for seven to 10 days; consequently, they tried not to schedule their vaccination in the week or two leading up to a race. The results of the Belgian study suggest that similar scheduling may be warranted for the booster. While you may only feel the effects of the booster for a day or two, its less discernable effects—like suppressed VO2 max—can still affect your race if you schedule it too close to the shot.

Go Light Around Your Booster

Amy Yoder Begley, coach of the Atlanta Track Club, says that what her team found worked best was to ease off training for the few days surrounding their booster. Typically, the athletes would do a light day of training on the day of the booster and then go home, hydrate, and focus on moving their arm throughout the rest of the day. They’d take the next day off to let their body recover and then, depending how they felt, they’d slowly ease back into training.

“I just kept telling people: literally you’re talking two to five days to let the body do its thing to give you more protection down the road, if possible,” says Begley.

Rosario has a similar message: “My advice to all runners would be to be patient. What’s the harm in missing some training if you’re going to come back super healthy?”

The future of American distance running may have just announced itself.

Luke Surface, an 8th-grade student-athlete from North Raleigh Christian Academy in Raleigh, North Carolina, delivered a performance that stunned the track and field community after taking on some of the nation’s best high school runners at Nike Outdoor Nationals.

Competing at the legendary Hayward Field in Eugene, Oregon — one of the most iconic venues in American distance running — Surface lined up in the boys championship 5,000 meters against a field dominated by high school seniors, including several athletes preparing to compete at the NCAA Division I level.

Despite being one of the youngest runners in the race, the 14-year-old held his own against the elite competition, finishing eighth in an incredible 14:25.88. The performance set a new national middle school record, averaging approximately 4:39 per mile for more than three miles.

That kind of time is fast enough to win many high school state championships across the United States and meets qualifying standards for several major NCAA Division I conference competitions — a remarkable achievement for a runner who has not yet entered high school.

But Surface’s historic 5,000m performance was only the latest chapter in a season filled with record-breaking moments.

Earlier in May, he clocked 8:52.03 for 3,200 meters at the NCISAA Division I State Championships in North Carolina, breaking another national middle school record. His converted two-mile time of 8:55.12 surpassed the previous world-best mark for a 14-year-old age group, previously held by Vincent Recupero.

During the previous cross-country season, Surface also made headlines when he ran 15:12 at the adidas XC Challenge, finishing second while competing against runners who were several years older.

Across cross country, two miles, and the 5,000 meters, Surface has continued to prove that his talent is far beyond his age group. While he still has four years of high school competition ahead before reaching the college level, his performances have already placed him among the most exciting young distance runners to watch.

The American high school 5,000-meter record currently stands at 13:32, set by Lex Young in 2023 — a mark Surface is not yet close to challenging. However, his remarkable progression at such a young age has caught the attention of the running world, with many eager to follow how far his extraordinary journey can go.

For now, Luke Surface remains an eighth grader rewriting the record books — and his story is only beginning.

DOHA, Qatar – Ethiopian distance running is once again making a powerful statement on the global stage. Following the Doha Diamond League meeting, Ethiopia has achieved a remarkable clean sweep of the women's 3000m/5000m standings, occupying all eight leading positions in one of the most competitive disciplines in world athletics.

Leading the charge is Likina Amebaw, who sits comfortably at the top of the rankings with 22 points. Close behind is fellow Ethiopian star Freweyni Hailu on 14 points, while Medina Eisa occupies third place with 12 points. The dominance continues through the rest of the leaderboard, with Senayet Getachew, Hawi Abera, Aleshign Baweke, Marta Alemayo, and Bernesh Dessie completing an extraordinary Ethiopian monopoly of the standings.

The achievement highlights Ethiopia's exceptional depth in women's distance running, where a new generation of athletes continues to emerge and challenge for global honours. Rather than relying on a single standout performer, Ethiopia has assembled a formidable squad capable of controlling races and collecting points across multiple Diamond League meetings.

While the current standings paint a picture of complete Ethiopian supremacy, the battle for the Diamond League title is far from over. Several meetings remain on the road to the season finale, leaving plenty of opportunities for rivals to close the gap and for positions within the Ethiopian contingent to shift dramatically.

For now, however, the spotlight belongs firmly to Ethiopia. The East African powerhouse has transformed the women's 3000m/5000m standings into an all-Ethiopian affair, sending a clear message to the rest of the world that the race for Diamond League glory will likely run through Addis Ababa.

The question now is whether Likina Amebaw can maintain her advantage and finish the season as the overall leader, whether Freweyni Hailu or Medina Eisa can mount a successful challenge, or whether another athlete will produce a late-season surge to rewrite the script.

One thing is certain: the road to the Diamond League Final promises a fascinating battle among some of the finest distance runners on the planet.

Kenyan athletics superstar and world champion Beatrice Chebet has officially entered a beautiful new chapter in her life after welcoming a baby boy.

The 26-year-old track sensation, born on 5 March 2000, has built a remarkable legacy as one of the greatest distance runners of her generation. Chebet is a world record holder in the 5000m, 10,000m and road 5km, with a career decorated by historic victories on the biggest stages.

She made history at the 2024 Summer Olympics by winning gold medals in both the 5000m and 10,000m, before achieving the same remarkable double at the 2025 World Athletics Championships. Her medal collection also includes a 5000m silver medal at the 2022 World Athletics Championships and bronze at the 2023 World Athletics Championships.

Beyond the track, Chebet has also dominated cross country, becoming a three-time world champion after winning the junior title in 2019 and senior titles in 2023 and 2024. She has also claimed major 5000m victories at the 2018 World U20 Championships, 2022 Commonwealth Games and the 2022 African Championships in Athletics.

Now, the Kenyan star is celebrating a different kind of milestone — becoming a mother.

Sharing the joyful news, Chebet introduced her newborn son with a heartfelt message filled with love and excitement:

“Tiny hands, tiny feet, and a love so big! A beautiful new chapter begins. Welcome to our world our sweet little baby boy!”

The arrival of her son marks a special moment away from competition, as the world champion embraces motherhood while carrying the pride of a nation that has watched her achieve greatness.

Messages of congratulations have poured in from fans and the athletics community, celebrating the new chapter for one of Kenya’s most successful athletes.

As Beatrice Chebet adds motherhood to her list of remarkable achievements, the champion now begins a new journey filled with love, joy, and unforgettable moments with her baby boy. 

Jake Wightman delivered a masterclass in championship racing as he surged to the men's 800m title at the UK Athletics Championships, holding off a determined challenge from Ben Pattison in a thrilling finish.

In a race defined by patience, positioning, and precise execution, Wightman waited for the perfect moment to strike before unleashing his finishing kick down the home straight. The former world champion crossed the line in 1:45.40, just doing enough to edge Pattison and secure the national crown.

The contest lived up to expectations, bringing together two of Britain's finest middle-distance talents in a tactical battle where every move carried significance. With the pace controlled through the early stages, the field remained tightly packed, setting the stage for a dramatic final lap.

As the bell rang, the intensity immediately rose. Pattison looked poised to seize control and pushed hard in the closing metres, but Wightman's experience and race awareness proved decisive. Drawing on years of competing at the highest level, he maintained his composure under pressure and found the extra gear required to stay ahead when it mattered most.

The victory marks another significant chapter in Wightman's decorated career and serves as a timely statement of intent as the international season gathers momentum. More importantly, it showcased the qualities that have made him one of Britain's most respected middle-distance athletes — tactical intelligence, resilience, and an ability to deliver in the biggest moments.

For Pattison, the narrow defeat will provide encouragement rather than disappointment. His performance confirmed his growing status among Britain's elite 800m runners and highlighted the depth of talent currently thriving in the event.

But on this occasion, the spotlight belonged to Wightman. In a race where the margins were razor-thin, he executed his plan to perfection and walked away with the UK Athletics Championship title.

Remember the name Gout Gout.

At just 18 years old, the Australian sprint prodigy is already commanding global attention and fueling conversations about the future of track and field. In a sport constantly searching for its next superstar, Gout is rapidly emerging as one of the brightest talents the world has seen in years.

His latest statement came at the prestigious Ostrava Golden Spike meeting, where he stepped onto the track alongside some of sprinting's biggest names, including reigning world champion Noah Lyles. Far from being overwhelmed by the occasion, the teenager delivered a composed and confident performance, finishing third in the 150m in 14.96 seconds against two of the fastest athletes on the planet.

Yet impressive as that performance was, it is not the result that has the athletics community buzzing most.

Earlier this year, Gout stunned the sprinting world by clocking an astonishing 19.67 seconds for 200m, setting a new world Under-20 record. The performance instantly elevated him from promising prospect to genuine phenomenon.

What makes the achievement even more remarkable is the historical context. At the same age, Gout was faster than sprint legend Usain Bolt. Comparisons to the Jamaican icon are inevitable, not because records demand them, but because the raw numbers are impossible to ignore.

Of course, Gout's journey is only beginning. Like any young athlete, he still has room to grow, refine his craft, and gain valuable experience at the highest level. The road from teenage sensation to global champion is rarely straightforward.

But there is no denying the extraordinary potential that lies within him.

His speed, composure, and ability to perform under pressure have already marked him out as one of athletics' most exciting young stars. More importantly, he possesses the kind of talent that inspires belief that a new era of sprinting may be on the horizon.

The sport has always thrived on rivalries that capture the imagination of fans across the globe. With established champions such as Noah Lyles currently leading the way, the emergence of Gout Gout adds an intriguing new chapter to sprinting's future.

The next great rivalry may already be taking shape.

And one of its leading figures is still only a teenager.

For now, the message is simple: remember the name Gout Gout. The future is arriving faster than anyone expected.