Abstract: The health problem caused by physical inactivity has become a worldwide public health problem, but exercise with reasonable intensity provides the possibility to solve this problem. The talk test is a method to judge the exercise intensity according to the degree of comfort during speaking or the maximum counting during a single breath. Talk test is mainly divided into two categories, i. e., normal talk test and counting talk test. Talk test has high reliability and validity in the general population, patients with chronic diseases, and some professional athletes. A decrease in breathing rate caused by speech, which further leads to a decrease in the volume of air per minute and an increase in the PCO2, is considered to be a possible mechanism for the decrease in speaking comfort during the talk test. Training with an exercise intensity which was determined by the talk test has been shown to be effective in improving cardiorespiratory capacity. Talk test has the characteristics and advantages of simpleness, cost-free and effectiveness, which provides a convenient choice for selecting and controlling the intensity of exercise and improving the pertinence and effectiveness of exercise.