The thigh muscles are divided into anterolateral group, posterior group and medial group. The quadriceps femoris is the anterolateral group and one of the most powerful muscles in human body. It includes rectus muscle, middle thigh muscle, outer thigh muscle and inner thigh muscle. The function of these four muscles is to keep the femur vertical to keep the human body upright and help squat and stand. The anterolateral group also has sartorius muscle and tensor fascia lata muscle, which is one of the longest muscles in human body. The former can bend and rotate the thigh and bend and rotate the calf, such as the leg movement when kicking shuttlecock; The latter can bend and pronate the thigh, and also play an auxiliary supporting role in the muscle contraction of the thigh.

The muscles in the back group are biceps femoris, semitendinosus and semimembranous muscle. The function of biceps femoris is to bend and rotate the calf and extend the thigh backwards; Except for calf pronation, semitendinosus and semimembranous muscles have the same function as biceps femoris.

The muscles in the medial group are adductor, pubis, adductor brevis, adductor longus and gracilis. These muscles ensure the adduction, supination, extension and bending of the thigh and the bending and pronation of the calf.

Leg muscles are divided into anterior group, posterior group and lateral group. The function of anterior muscles is to make feet and toes complete various activities; Posterior muscles play an important role in pushing back during running and taking off during jumping; The main function of lateral muscles is to maintain the arch of the foot.

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 overall strength, but also the basis of bodybuilding. If the thigh and calf muscles are underdeveloped, the better the upper body muscles are trained, the more deformed people will be, and the body shape will not be symmetrical and fit.

The weight-bearing squat barbell is placed behind the neck and shoulders. Hold the pole with both hands, stand up straight, hold your chest and abdomen, and keep your back muscles tense. Then kneel down until the knees are completely flexed, then stop, straighten your legs and stand up with the contraction force of the quadriceps femoris, so that the quadriceps femoris tightens and stops. Get down again. There are two ways to breathe in this movement: exhale when squatting under light load and inhale when standing up; Under heavy load, inhale first, then squat down, exhale before standing up, inhale again and stand up. In practice, when doing the last few squats, such as shortness of breath, you can also breathe several times after standing up to absorb more oxygen. When doing movements, your mind should focus on the quadriceps femoris. This action can also be practiced by holding dumbbells in both hands or carrying sandbags and rice bags on your shoulders. Sit with your legs straight, wear iron shoes (dumbbells or sandbags can also be tied to your feet), straighten your legs with the contraction force of quadriceps femoris, tighten quadriceps femoris as much as possible, stop for a while, and then put it down and do it again. Inhale when the calf is straight, and exhale when the calf is lowered. Thought should focus on quadriceps femoris. Both calves can be straightened at the same time or alternately.

Bend your legs and lie prone on a prone stool. Wear iron shoes on your feet (dumbbells or sandbags can also be tied to your feet). With the help of the contraction force of the biceps femoris, make both calves bend towards your thighs at the same time, tighten the biceps femoris as much as possible, stop for a while, and then put it down and do it again. Inhale when the calf flexes and exhale when it is lowered. Thought should focus on biceps femoris.

The load-bearing person who lifts the Lift heel upright puts the barbell behind his neck, and his feet stand on a board with a thickness of 10cm, with his heels exposed. Lift the heel with the contraction force of the calf triceps, so that the calf triceps can be tightened as much as possible, stop for a while, and the heel falls until it falls below the board, and can't be lower. Then do it again. Inhale when lifting the heel, and exhale when lowering the heel. Attention should be focused on the triceps surae. The board is placed under the foot to fully stretch the triceps surae. In this way, when lifting the heel, you need more strength to get a more thorough exercise of the triceps surae. The action is the same as the weight-bearing squat, except that all the toes are used to bear the weight when squatting and standing up. When the legs are completely straight, put down the heel to relax the triceps of the calf, and then raise the heel to support the body with toes. Inhale when you stand up, exhale when you squat down, and focus your thoughts on the triceps surae.

Sitting posture: Heel lifting is a sitting posture, the barbell is placed on the thigh, close to the knee, the lever is held with both hands, the sole of the foot is stepped on the board with the thickness of 10 cm, and the heel is exposed. Lift the heel to tighten the triceps as much as possible, stop for a while, and drop the heel below the board until it can't be lower. Then do it again. Inhale when lifting the heel, and exhale when lowering the heel.