IntroductionIn recent years, physical exercise has attracted more and more attention. Regular physical exercise can not only keep people healthy, but also do good things to the muscles. Made up of muscle tissue, muscles play an important role in bodily functions. Muscles can be divided into three types: skeletal muscles, smooth muscles and cardiac muscles. Smooth muscles and cardiac muscle are involuntary and do not contract according to the will of human beings. Skeletal muscles are voluntary and represent approximately 40% of total body weight. Muscles are essential for maintaining normal physiological functions because they can produce movement, maintain posture, stabilize joints, and generate heat. The purpose of this report is to study the effect of exercise on muscles. I will discuss the effect on mitochondria, muscle fibers, capillaries and other aspects. Changes in muscle elements If muscle activities last for a long time, the muscles will contract less effectively and muscle fatigue will occur due to lack of oxygen. Generally speaking, exercise can lead to stronger, more flexible muscles, as well as greater resistance to fatigue. Long-term physical exercise can change elements of muscle tissue. For example, the amount of muscle glycogen, muscle myosin and muscle hemoglobin increases. Increasing these elements can improve the activity of the ATP enzyme and strengthen the contraction ability of muscles. In the mitochondria, glucose is broken down into carbon dioxide and water. During this process, energy is generated which can be used to attach a phosphate molecule to ADP to make ATP. However, if there is not enough oxygen, lactic acid will be produced, which can lead to muscle fatigue. If the activity of the ATP enzyme is improved... middle of paper ...... do medium and low intensity exercises such as brisk walking and jogging. Conclusion Muscles play an indispensable role in normal physiological functions. Without muscles, people are unable to play ball, run and swim. Muscles allow people to exercise, and exercise can have a positive effect on muscles in return. The report aims to study the effect of exercise on muscles. Exercising can change elements of muscles such as muscle glycogen, muscle myosin, and muscle hemoglobin. Additionally, exercising can increase the amount of mitochondria that can provide energy to muscles. Additionally, exercise can lead to improvements in the cardiovascular and respiratory systems as well as the capillary network. It can also increase muscle cell volume and strengthen muscles. However, it is important to choose appropriate activities and exercise intensity..