As cold and flu season approaches, those who want to prevent from getting sick will pay extra attention to eating well, washing their hands, sleeping for no less than eight hours per night and taking their vitamins. All of these things usually come to mind when one thinks about preparing one's immune system for this time of year, but exercising does not.
But, believe it or not, mild exercise could strengthen one's immune system toward the common cold and influenza, according to a recent article in The New York Times.
A 2008 experiment published in the Brain, Behavior, and Immunity journal, which was cited in the same Times article, indicates that exercise stress increases one's susceptibility to illness.
In the experiment, scientists at the University of Illinois and other universities injected the influenza virus into laboratory mice, according to the Times article.
After splitting the mice into three groups, scientists controlled and regulated each group's exercise routine.
They discovered that the group with a moderate exercise routine had the lowest mortality rate, while the group with a severe exercise routine had the highest mortality rate.
The mice that did not exercise at all had a lower mortality rate than those that exercised until they were exhausted, but a higher mortality rate than those that had a mild exercise routine.
According to the Times article, the same trend holds true for humans: exercise at a moderate level improves immune function.
Generally, a moderate exercise routine is somewhat in the range of 30 minutes, three days per week, according to an e-mail from Eric Morrow, a personal trainer at the UF Student Recreation and Fitness Center.
A typical high volume workout, on the other hand, is somewhere in the range of one to two or more hours, five to six days per week, Morrow said.
Brendan Ryan, a personal trainer and wellness appraiser at UF SRFC, said he realizes that exercise is not the first thing that comes to one's mind when one wants to prevent from getting sick.
"Most people go to the gym to get fit, not to strengthen their immune system," Ryan said.
"But a better cardiovascular system [which could result from exercising] could boost one's immune system," he said.
UF psychology senior Maeghan Cook said she's been exposed to the influenza a lot this semester, but hasn't gotten sick. Cook said she exercises regularly.
"I think I have a strong immune system because I work out," she said.
Cook also believes in the psychological benefit of exercising.
"Exercising is stress-relieving for me, and there's a lot of self efficacy in it," Cook said.
The effect of exercise on the immune system also holds true for those who have already caught the cold or influenza, according to experiments conducted by the same scientists from the University of Illinois.
When one is ill, moderate exercise tends to expedite the recovering process while severe exercise tends to slow it.
Lisa Moran, a UF health education and behavior junior, said she usually continues to work out when she gets the common cold.
"I kind of tell myself I'm not sick and go through my workout normally," she said.
But according to UF Student Health Care Center spokesman Guy Nicolette, one should not work out when one has a temperature of 104 degrees or more. He also said that in terms of exercising, the rules for when one has H1N1 swine flu are no different than the regular influenza.
"Once your fever has gone away for 24 hours, you should be able to start exercising regularly again." Nicolette said in a phone interview.
The UF SRFC has a general rule when it comes to working out when one is sick. If one's symptoms are below the neck, like respiratory infections, an upset stomach, fever and chills, then one should not workout, Morrow said in an e-mail.
It's only OK to exercise when the illness is above the neck, he said.
However, in terms of immunity, if one is exercising too hard, exercising while one is sick will generally debilitate the immune system, regardless of where one's symptoms lie, Morrow said.
UF freshman Sunny Welsch said she exercises on a regular basis and hasn't gotten sick this semester. However, she credits her health to more than just exercising.
"I think people who exercise care more about their health in general," Welsch said. "I exercise but I take my vitamins, too."
Correction: The Alligator incorrectly reported that mice with a moderate exercise routine had the highest mortality rate. The study found that group to have the lowest rate.
The article also indicated that the mice that did not exercise at all had a higher mortality rate than that exercised until exhaustion, but a lower mortality rate than those with a mild exercise routine.
The mice that did not exercise had a lower mortality rate than those who exercised until exhaustion, and a higher mortality rate than those who had a mild exercise routine.
