Evidences showing that smoking Endangers Health

Tar in the cigarette smoke may lead to lung cancer.

The greater the number of cigarettes smoked per day, the higher is the chance of death from lung cancer.

The non-smoker has the lowest risk of death from lung cancer. Once smoking was given up, the chances of death from lung cancer is reduced. The longer the period of giving up smoking, the lower is the risk of death from lung cancer.

The effect of exercise on the rate and depth of breathing and its relation to energy requirements

The rate and depth of breathing increase during exercise.

The increase in rate and depth of breathing brings more oxygen into the lungs and removes more carbon dioxide. This is necessary to provide more energy for vigorous muscular activity.