Yes that is true. It is important to stay safe because you can’t help someone if you start having a problem too. Don’t put yourself in danger unless you are a medical professional
the respiratory system and the circulatory system work closely together to deliver oxygen to cells and to get rid of the carbon dioxide the cells produce.
Answer:
Most runners don't think of themselves as muscle-bound.
That's a term reserved for football players, weight lifters, or Charles Atlas when he kicks sand in the face of a skinny runner on the beach.
But the reality is that the human body has more than 600 muscles. We runners use most of them. And training sessions designed to recruit and strengthen our running muscles are the key to achieving top fitness.
C. H<span>ow hard a person works to do an activity.
Intensity has to do with effort. If a person works hard than they are intense, if vise versa than they are not intense.</span>