For your health, you may want to learn how to exercise as if it were summer all year long. An 18-month-long study of postmenopausal women found that they worked up more of a sweat in the summer than in any other season, and not just because it was hotter. The women got more exercise in summertime, as measured by pedometer readings and answers to an activity questionnaire. But when a group of study participants was put on a healthy diet and a program of 150 minutes of exercise a week, they maintained a higher level of physical activity year-round. In terms of exercise at least, it was like an endless summer.
Source: Medicine & Science in Sports & Exercise, February 2009