Explained: Why Singapore is urging people to avoid exercise for a week after getting a Covid-19 vaccination

While the advisory applied to all those seeking vaccinations, it focussed particularly on adolescents and men below the age of 30. “We recommend that everyone, in particular adolescents and younger men, aged younger than 30, avoid strenuous physical activity, such as intense exercise, for one week after the first and second doses,” the Ministry’s updated guidelines read.

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Why is Singapore asking people to avoid exercise after the Covid vaccine?

The updated guidelines were based on reports of young men experiencing heart problems after receiving the shot. Most recently, a 16-year-old boy suffered from cardiac arrest while lifting weights on July 3, days after receiving his first dose of the Pfizer-BioNTech vaccine.

“The preliminary diagnosis of his condition is an out-of-hospital cardiac arrest. Clinical and laboratory tests are in progress to understand the underlying cause,” the Health Ministry explained on Monday. “This will include a thorough consideration of whether there was acute severe myocarditis, which is severe inflammation of the heart muscles affecting the heart function, as a possible diagnosis.”

Apart from the Pfizer-BioNTech vaccine, Singapore is also offering the jab developed by Moderna.

As of June 30, Singapore’s Health Science Authority has received reports of heart problems experienced by at least 12 people following their vaccinations. A majority of these cases involved men aged 30 and below, Bloomberg reported.

The advisory comes based on emerging data, which suggests a slight risk of myocarditis (inflammation of the heart muscle) and pericarditis (swelling of the membrane surrounding the heart) associated with Covid vaccines.

“During this time, the vaccinated persons should seek medical attention promptly if they develop chest pain, shortness of breath or abnormal heartbeats. All doctors should also be vigilant around such clinical presentations after vaccination,” the advisory stated.

What forms of exercise should be avoided according to Singapore’s Health Ministry?

As per its latest advisory, activities such as swimming, cycling and running should be avoided for one week after the first and second doses of the vaccine. The list of avoidable activities also included lifting heavy weights, jogging, competitive sports, ball and racket games.

It also states that physical education classes in schools should be avoided. Physical activities that are safe to do after one week include walking, stretching and housework.

Has an advisory like this only been issued in Singapore?

No. Both the United States and Israel have also adopted a similar stance on exercise after receiving the vaccine. This is because of a few cases of myocarditis reported among young men after they received the Pfizer vaccine.

Last month, the US Food and Drug Administration announced that it was adding a warning about rare cases of heart inflammation in adolescents and young adults on all fact sheets about the Pfizer and Moderna Covid-19 vaccines.

Meanwhile, in a report submitted to the Israeli Ministry of Health, researchers said that the vaccine made by Pfizer and BioNTech appears to put young men at elevated risk of developing myocarditis.

But the expert committee advising the Singapore government on its vaccination drive continues to recommend inoculation against the deadly virus, arguing that the benefits outweigh the potential risks. Both Israel and the US have also maintained that these vaccines are integral in fighting the pandemic.

What other vaccine advisories have been issued around the world?

Several advisories have been issued across the world, urging citizens to avoid certain activities after receiving the vaccine.

Late last year, Russian health officials advised citizens to avoid alcohol for around two months after receiving the shot. The warning did not go down well with a wide section of Russians, who believe the request was unreasonable. However, soon after, Sputnik V vaccine’s developer contradicted the claim.

Meanwhile, Germany has been issuing a strong recommendation for mixing Covid vaccines on efficacy grounds. In fact, German Chancellor Angela Merkel herself took the AstraZeneca vaccine as her second dose, after receiving Moderna as her first.