Leg muscles are divided into front, back and sides. The function of the front muscles is to enable the feet and toes to complete various activities; The latter group of muscles plays an important role in run-up and take-off. The thigh muscle group is one of the most powerful muscles in the human body. It can be said that it is not only the basis of physical strength, but also the basis of bodybuilding. If the thigh and calf muscles are underdeveloped, the upper body muscles will be better, and more people will be deformed, unbalanced and healthy. The barbell squats behind the neck and shoulders, the hands of the bar stand upright, and the muscles of the chest, abdomen and back remain tense. Then squat down until your knees are fully flexed, pause, stand in the quadriceps femoris to contract your legs, straighten your legs, and make the quadriceps femoris tighten and pause. Get down again. There are two ways to breathe in this movement: under light load, squat when exhaling, and inhale when standing up. Under heavy load, inhale first, then squat down, stand up and exhale, then inhale and rise. When practicing, do the last few squats, such as shortness of breath, and take a few quick breaths after standing to attract more oxygen. Focus on the four muscles in stock when moving. This action can also be practiced by lifting dumbbells or sandbags with both hands. Stretch your legs in a sitting position, wear iron shoes (or tie dumbbell sandbags on your feet), contract quadriceps femoris to straighten your legs, tighten quadriceps femoris, pause, and then lie down. The calf is straight when inhaling and downward when exhaling. The idea should focus on the biceps femoris quadriceps. Both legs can be straightened at the same time or alternately. Bend your prone legs to the prone stool, put on iron shoes (or tie dumbbell sandbags to your feet to contract two muscles), bend your legs to your thighs at the same time, tighten and pause two muscles, and then put them down. When inhaling, bend your legs and exhale. The idea should focus on two biceps. Vertical weightlifting heel barbell The barbell is placed on the shoulder behind the neck, with feet standing on a 0 cm thick board and heels exposed on the wood. Contraction force of calf triceps, lifting heel, tightening and suspending triceps brachii, lowering heel, lower than wooden surface, so far. Then do it again. When you lift your heel and exhale, when you put your heel down. The idea should focus on the triceps surae. Foot board, in order to fully stretch the triceps surae, so as the heel, you need to spend more strength to make the triceps brachii get more thorough exercise. The action is as heavy as squatting, but squatting and standing on tiptoe with weight. When the legs are completely straight, put down the heel to relax the triceps brachii, then raise the heel and support the body with toes. Stand up when exhaling, squat down when exhaling, and focus on the triceps surae. Sit in a weight-bearing posture, put the barbell on your thighs, close to your knees, hold the barbell with both hands, and put your feet on a 0 cm thick board to expose your heels. Lift the heel, tighten the triceps, pause, and drop below the heel plate until it is no longer so low. Then do it again. When you lift your heel and exhale, when you put your heel down.