Even sitting at your desk requires muscles. When you exercise, you ask your muscles to do more than they normally do in regular activities. Your muscles must get bigger and stronger in order to be able to do the exercise you are having them do. Physical activities like sports and play help make the bones more solid and sturdy. Muscles and bones work together to produce movement and support the body.
Physical activity helps people feel happy.
Physical activity is something we can do with friends. Discuss how physical activity helps the heart. Discuss ways that physical activity helps make hearts strong. The heart is a muscle just like the muscles in our arms and legs. When we work our muscles, they get stronger.