Let’s start by what exercise really is. Exercise is any physical activity that exerts yourself at a higher intensity than normal, and increases the heart rate beyond resting levels. Depending on your age, current health conditions and physical level, is going to determine what is considered exercise. Someone who is very active and physically fit may not get taxed by push mowing the grass. On the other hand, it may increase someone else’s heart rate and physical activity in one who is less active, which would be considered exercise for them.