Gender differences due to different levels of hormones in the body do affect lung capacity and respiratory performance, according to a study published by the National Institutes of Health. For the most part, lung capacity is dependent on the size of a body. Because of this, women tend to have smaller lung capacity than men because they are smaller in size. In addition, research has found that lung capacity and respiratory performance can depend on gender.
Reproductive hormones in women have been shown to lower aerobic power and pulmonary function. Women have a smaller diffusion area than men of the similar size, which can result in poor respiratory performance and lung function. Specifically related to exercise, it is believed that women have to work harder and maintain an increased level of breathing compared to men.