Body fat is lost. The muscles and blood carry and utilize oxygen better. Blood fats like cholesterol and triglycerides are decreased. The risk for blocked arteries is reduced. The body can better tolerate stress.
Exercise is aerobic when it is done at low to moderate intensity without stopping to rest.
In order to keep moving, the muscles are forced to use a lot of oxygen. Examples are walking, hiking, swimming, jogging, bicycling, aerobic dancing, and cross country skiing. Gets you breathing deeply but not out of breath. Uses the muscles in the thighs and buttocks. Get moving if you want to be healthy, fit, and trim.