Study concludes that weekend exercise is important: Study author Clemens Drenowatz, an assistant professor of exercise science at University of South Carolina found a 20-minute reduction in sedentary time on weekends added up to a loss of more that 2 pounds and 1.6% body fat after one year. Why you ask? The average person consumes more calories and eats less healthy on the weekend and the added activity during weekends helps to offset the increase in calories consumed and poor diet.