If you stay physically active during the day, you are more likely to sleep well at night. Everyone needs physical activity to keep their body healthy. Physical activity relieves stress and helps the body perform its functions. When we feel tired through doing activities, we are more likely to relax physically and mentally at night. This helps you get to sleep and stay asleep. Exercise also helps to keep you in a good mood and has been show to help with depression. 15 minutes exercise twice a day is a good start.