Using the commercially available finger clip pulse oximeter as teaching aid to design and measure the changes of blood oxygen and pulse before and after exercise as the main practice activity, the junior high school students can understand the trend of blood oxygen saturation dropping and heart rate rising after exercise and gradually recovering after rest from intuitive data in real situations, and agree with the idea that exercise can increase cardiopulmonary function and penetrate healthy life. This activity effectively helps students to make it possible from phenomenon perception to rational cognition, deepens the connotation of biological concepts, enhances scientific thinking, forms the concept of homeostasis and regulation, and lays the foundation for subsequent learning of neurohumoral regulation mechanism.