What modifications might be made to a cardio vascular workout to ensure that a person remains in their target heart rate zone

Ihave a really high metabolism and only weigh 70 pounds (13 almost 14). people always ask me two questions: do you ever eat and how do you eat so much and stay so skinny. i am worried that a high metabolism wont me forever. what are some safe steps i can take to maintain being fit. (also, i already work out i am a dancer so i get cardio a lot)

Exercise has no positive effects on the nervous system? true or falseu

Last 5 benefits of physical activity and identify each benefit as either a physical mental and emotional or social benefit