Answer:
Respiratory
Explanation:
The respiratory system is what helps you breathe, so the circulatory system would be sending oxygen there.
Answer:
The principle of progression states that you should increase overload, which can be achieved by using FITT (frequency, intensity, time, and type) when your body adapts to its present routine. The specificity principle states that only targeted exercises will improve specific fitness goals.
Explanation:
Genetics, Pollution, Family history.