The human body and brain both need adequate amounts of exercise on a regular basis in order to function well. Going on a 3-hour-bike ride over a weekend does not compensate for 12 hours per day of sitting. The consequences can be increased weight gain for children as well as adults, lowered brain function (as vigorous exercise helps sweep the brain of waste products and replenish nutrients), and so on. Richard Restak, MD, has been quoted as saying: “Physical exercise is the single most powerful tool you have to optimize your brain function.” A study of 11-year-old children shed some light on this. . Moderate to vigorous exercise was linked with improved academic performance in Science, Math, and English. The improvement was also seen in exams scores of tests taken when the study participants were 16 years old. Of particular interest, science improvement among girls benefited the most from extra exercise.