Flu vaccine potentially more effective with exercise, study says

NEW YORK, NY - JANUARY 10: Aaron Lemma receives a flu shot by Dr. Sassan Naderi at the Premier Care walk-in health clinic which administers flu shots on January 10, 2013 in New York City. The Flu season has hit parts of the country particularly hard this year with Boston declaring a public health emergency and a Pennsylvania hospital constructing a tent to handle excess flu cases.According to the Centers for Disease Control and Prevention, 22,048 flu cases have been reported from September 30 through the end of 2012. (Photo by Spencer Platt/Getty Images)
Spencer Platt

(CBS News) If you get vaccinated, you're 62 percent less likely to get the flu, according the U.S. Centers for Disease Control and Prevention. But a new study by Iowa State University reveals a way to possibly make it even more effective. All you have to do is exercise after getting vaccinated.

Researchers separated young healthy adults into two groups. The first went for either a 90-minute jog or 90-minute bike ride after receiving a flu shot. The second sat quietly for 90 minutes after the shot. Researchers then checked the blood levels of participants for flu antibodies. Those that exercised had nearly double the response of those that did not. They also had higher levels of cells that ward off infection.

To find the optimal amount of exercise, researchers ran another test on mice. After receiving a flu shot, some ran for 90 minutes, others ran for 45 minutes, and a third group ran for three hours. The mice that exercised moderately for 90 minutes became most resistant to the flu.

Experts believe that exercise helps the vaccine work by activating the immune system. Increased blood circulation may pump the vaccine through the body.

The flu shot is recommended for everyone six months and older. And if you can fit in a little exercise afterwards, you may be even better off.

Watch Dr. Holly Phillips' full "CBS This Morning" segment in the video above.