March 25, 2004 -- Intense bouts of exercise pumps up teen boys' immune systems. The finding suggests that the teen years offer a window of opportunity for lifelong resistance to disease.
The study, by Dan Cooper, MD, professor of pediatrics and director of respiratory and critical care research at the University of California, Irvine, Medical Center, focused on 11 high school boys aged 14 to 18.
The exercise: wrestling. The boys had their blood analyzed before and immediately after an hour-and-a-half wrestling practice. How intense was it? You be the judge. It included:
- 20 minutes of jogging, stretching, and calisthenics
- 20 minutes of 10-second bursts of practicing typical wrestling moves such as takedowns and pins
- 15 minutes of simulated wrestling, in which the boys were positioned and told to wrestle in 20-second bursts
- 15 minutes of the "iron man" drill, in which one boy wrestles a fresh wrestler in six back-to-back 30-second bouts
- 10 minutes of live wrestling
After the practice, the boys' immune systems teemed with various cells that make up the defense system's fighting power, such as natural killer cells, killer T lymphocytes, antibody-producing B cells, and various other markers of healthy immunity.
"The rapid and substantial immune response in the real-life exercise suggests that stimulation of the immune system often occurs in the lives of children and adolescents and may play a role in its development," Cooper and colleagues conclude.
The researchers suggest that there are distinct developmental periods during which exercise and fitness can have a huge impact on future health. It's not clear, they say, whether exercise during other life stages can have such a dramatic effect.
The findings appear in the current issue of the British Journal of Sports Medicine.
SOURCE: Nemet, D. British Journal of Sports Medicine, 2004; vol 38: pp 154-158.