Exercise can boost success of flu shots

A bout of exercise can strengthen immunity by increasing circulating cell numbers

Exercising at the time of having a flu shot may increase the success of vaccination, according to a new study.

The study from the University of Sydney found exercise is the key to successful vaccination.

Being physically active has been found to improve immunity in general, but specifically doing some exercise immediately before or after a vaccination can boost vaccine response in particular, said Dr Kate Edwards from the Faculty of Health Science's Exercise and Sport Science unit.

In a paper, published in journal Human Vaccines and Immunotherapeutics and co-authored by Professor Robert Booy, Edwards advised that a bout of exercise can bring about profound changes in the immune system, such as increasing circulating cell numbers, with specific increases in certain subsets, and the release of immune messenger proteins by working muscle cells themselves.

With vaccine success rates around 50 to 70 per cent, a large number of those vaccinated are receiving minimal benefit, which is often mentioned as a reason not to get the jab, researchers said.

People also avoid flu shots because of side effects like headaches and soreness.

But physical activity after a shot might not only make the vaccine work better, it might protect them from some side effects as well.

"We are almost certain that exercise can help vaccine response by activating parts of the immune system that means it's ready to respond when the vaccine is administered," Edwards said.

Edwards cited a study conducted by scientists at the Iowa State University in the US that showed mice who ran leisurely for about half an hour after vaccination showed maximum resistance to any side effects of the flu shot.

Conversely the mice who were sedentary and the ones who indulged in extreme exercises succumbed to the side effects.

Edwards also acknowledged that our bodies react in different ways and advises people not to overdo physical activity after a flu shot but engage in moderate activities such as cycling, or resistance exercise and avoid dehydration by drinking plenty of fluids.