Blood tests were performed several times over the next five months to measure the way the immune system responded to the vaccine. It was found that though the immune response differed in men and women who performed the exercise, both genders demonstrated an increased immune response to the vaccine when it was preceded by bicep curls.
This is significant because vaccinations work by exposing the body’s immune system to a tiny amount of the virus that causes the disease, in this case the flu. So, the better the immune system responds to a vaccine, in theory, the better able the body may be to defend itself against the flu.
Edwards believes that the immune response to the flu vaccine changes after exercise because of inflammation.
“Doing a [bicep curl] damages the muscle, causing immune cells to arrive in that area,” she says.
After exercise, muscles tend to get inflamed, and immune system cells flock to the area to try to ease the damage. With more immune cells in the area where the flu shot is given, more cells are quickly forced to respond to the vaccine.
