In a study of sports in Yin Shi, Shaanxi Province, researchers gathered 59 healthy but quiet volunteers, aged between 60 and 79. They were randomly divided into two groups. One group exercised with aerobic outdoor fitness equipment, and the other group exercised with "body shaping and stretching" outdoor fitness equipment for six months. Volunteers measured their brain size by scanning before and after the outdoor fitness equipment exercise program. The result is very interesting: the brain volume of the group who did aerobic outdoor fitness equipment increased obviously, but the group who only did body shaping and stretching exercise did not.