You already know that exercise is good for you. Thousands of studies, big and small, have outlined the physical and mental benefits of moving the body to increase the heart rate and burn calories. For example, regular physical activity can protect you against countless health conditions, like anxiety and depression, type 2 diabetes, stroke, heart disease, and many types of cancer. At least 150 minutes a week of moderate exercise, or 75 minutes per week of vigorous physical activity, can...