CDC | How much physical activity do children need?

Some physical activity is better-suited for children than adolescents. For example, children do not usually need formal muscle-strengthening programs, such as lifting weights. Younger children usually strengthen their muscles when they do gymnastics, play on a jungle gym or climb trees. As children grow older and become adolescents, they may start structured weight programs. For example, they may do these types of programs along with their football or basketball team practice.