Muscles usually develop in two to three months. The duration of the effect varies from person to person, which requires good physical fitness, appropriate exercise intensity and persistence. Generally speaking, the effect can be seen within two to three months. Every part of the exercise has different exercise methods, such as biceps brachii, dumbbell exercise, abdominal muscles and lumbar muscles, plane support or sit-ups. The most common movements of leg muscles can be squat and pull-ups.