Getting your heart beating faster than it's resting rate each day trains your body to move oxygen and blood to your muscles more efficiently. This helps your muscles use that fuel more economically as well, and ultimately you move with more ease. In other words, you end up in shape.
The drug that is associated when having to intake it when
pregnant that is likely causing premature birth, low birth weight infants and
the fetal death is the use of nicotine. This type of drug is a form of agonist
in regards with nicotinic acetylcholone receptors.