Strength Training Before Receiving Flu Vaccine Consistently Increases the Immune Response

As reported by the New York Times, exercise before having a flu shot may
make the vaccine more effective, British researchers have found.

Eccentric Exercise as an Adjuvant to Influenza Vaccination in Humans (Brain,
Behavior and Immunity)

A small study, published in the February issue of Brain, Behavior and
Immunity, found that lifting weights before a vaccination increased antibody
response in women, while reducing it in men. In men, cell-mediated response
— the activation of white blood cells and other kinds of cellular defenses —
was increased.

The scientists randomly divided 60 healthy men and women into two groups. A
group of 40 exercised by lifting weights for about 25 minutes before
receiving their flu shot. The remaining 20 rested for 25 minutes and then
got their shot. The scientists took blood samples from all of the
participants, then tested their blood again 6, 8 and 20 weeks later. They
found a consistently increased immune response in the exercisers.

Kate M. Edwards, the lead author, said that it could do no harm if everyone
exercised before being vaccinated.

“We don’t know for sure how this will work, but I think that if people go
out and exercise before a shot, that might be a good idea,” said Dr.
Edwards, a researcher in exercise immunology at the University of Birmingham
in England.

The authors suggest that exercise increases the number of immune cells that
arrive at the muscle tissue, which increases activity in the lymph nodes,
leading to a more efficient immune response.