(1) quadriceps femoris: 1. Anatomical location of quadriceps femoris is located in front of the thigh, with four heads: rectus femoris, middle femoris, lateral femoris and medial femoris. It is the largest muscle in the human body and is a feather muscle. 2. Starting and ending points and functions: (1) Starting point: The four heads of quadriceps femoris have different starting points, among which rectus femoris starts from the anterior inferior iliac spine, middle femoris from the front of the femoral body, lateral femoris from the lateral lip of the femoral thick line, and medial femoris from the medial lip of the femoral thick line. (2) Stop point: The four heads of quadriceps femoris combine to form a powerful tendon, which wraps the patella from the front and both sides and forms a patellar ligament under the patella, thereby stopping at the tibial tuberosity. (3) General function: when it is near fixation, the calf is extended, and the rectus femoris can also bend the thigh. When far fixed, the thigh can be extended at the knee joint. (4) Integration function: when the foot touches the ground, centrifugal contraction can resist knee flexion and pronation; Maintain the dynamic stability of knee joint when completing functional exercise form; When performing functional exercise, rectus femoris resists hip extension. (2) Sartorius muscle: 1. Anatomical location Sartorius muscle is located in the shallow layer of the anterior medial thigh, and its muscle fibers are inclined from the upper outer thigh to the lower inner thigh. It is the longest muscle in the human body and is spindle-shaped. 2. Starting point and function (1) Starting point: It starts from the anterior superior iliac spine. (2) Stop point: stop at the inner side of tibial tuberosity. (3) Function: When near fixation, make thigh bend and external rotation, and make calf bend and internal rotation; When far fixed, both sides contract, so that the pelvis leans forward. 3. Developing the sartorius muscle for example: The method of developing the sartorius muscle alone is generally rare, and the traditional shuttlecock kicking exercise is a good choice for developing the sartorius muscle. In addition, in order to develop this muscle more specifically, we can also design resistance exercises similar to shuttlecock kicking, such as using rubber strips or small barbells to carry loads. (III) Main muscle groups in the inner thigh: The muscles in the inner thigh mainly include adductor muscle, adductor minor, adductor longus, adductor brevis, gracilis and pubis. 1. Anatomical location: adductor longus, adductor brevis and pubis muscle are located on the inner side of the upper thigh; Adductor muscle is located in the deep layer of the inner thigh; The gracilis muscle is located in the superficial layer of the inner thigh. 2. Starting point and function: (1) Starting point: The pubic muscle and adductor longus muscle originate from the outside of the superior pubic branch; The adductor brevis originates from the outside of the inferior pubic branch; Adductor muscle originates from ischial node, inferior ischial branch and inferior pubic branch; The gracilis originates from the inferior pubic branch. (2) Stop point: the pubic muscle stops at the upper part of the medial lip of the femoral thick line; The adductor longus stops at the middle of the medial lip of the femoral thick line; The adductor brevis stops at the upper part of the femoral thick line; Adductor muscle stops at the upper 2/3 of the medial lip of the femoral thick line and the medial upper ankle of the femur; The gracilis muscle stops at the medial surface of tibial tuberosity: (3) Function: The pubic muscle, adductor longus and adductor brevis make the thigh bend, adductor and supinator when they are near fixation, and make the pelvis lean forward when they are far fixation. Adductor muscle makes the thigh adduction, extension and external rotation when it is near fixation, and makes the pelvis backward when it is far fixation. When the gracilis muscle is fixed near, the thigh can be adducted, the calf can be flexed and pronated, and the pelvis can be tilted forward when it is fixed far away. (4) Gluteus maximus: 1. Anatomical position of gluteus maximus: The gluteus maximus is located in the posterolateral part of the pelvic cavity, under the buttocks, with a generous square shape and thick muscle fibers. 2. Starting point and function (1) Starting point: Starting from the outside of iliac wing and the back of sacrum and coccyx. (2) Stop point: stop at gluteal muscle tuberosity and iliotibial tract. (3) Function: When near fixation, make the thigh extend and rotate outwards; When distal fixation is performed, one side muscles contract to make the pelvis turn to the opposite side, and both sides contract at the same time to make the pelvis lean back. (V) Muscles behind the thigh: The muscles behind the thigh mainly include biceps femoris, semitendinosus and semitendinosus. 1. Anatomical location: Biceps femoris is located on the superficial side of the posterior lateral thigh, and it is a spindle muscle with long and short heads; Semitendinous muscle and semimembranous muscle are located in the posterior medial thigh, and semimembranous muscle is in the deep layer of semitendinous muscle. The lower part of semitendinosus muscle is tendon, and the upper part of semimembranous muscle is membrane, all of which are pinnate. 2. Starting point and function: (1) Starting point: The long head of biceps femoris starts from the ischial tubercle, and the short head starts from the lower half of the lateral lip of the femoral pachytene. The semitendinosus and semimembranous muscles originate from the ischial tubercle. (2) Stop point: the biceps femoris stops at the fibular head; Semitendinous muscle stops at the medial surface of tibial tuberosity, and semimembranous muscle stops at the medial surface of medial condyle of tibia. (3) Function: When the biceps femoris is near fixed, the head makes the thigh stretch, and makes the calf bend and rotate outward, and when it is far fixed, the thigh bends at the knee joint. The semitendinosus and semimembranous muscles stretch the thigh and bend and pronate the calf when they are near fixation. When far fixed, the function is the same as that of biceps femoris. (6) iliopsoas muscle: 1. Anatomical position of iliopsoas muscle: The iliopsoas muscle is located on both sides of the lumbar spine and in the iliac fossa, and consists of psoas major and iliopsoas muscle. 2. Starting point and function: (1) Starting point: psoas major starts from the 12 thoracic vertebra and the 1? 5. Lateral surface and transverse process of lumbar vertebrae; Iliac muscle originates from iliac fossa. (2) Stop point: the two muscles meet and pass through the deep surface of the groin of the anterior and medial hip joint. (3) General function: Centripetal contraction helps hip flexion and hip external rotation, and muscles of both sides contract at the same time when they are far fixed, which can make trunk bend forward and pelvis lean forward. (4) Complete function: centrifugal contraction prevents hip extension. When the foot is fixed, centrifugal contraction prevents the thigh from pronation; Maintain the stability of waist, pelvis and buttocks during functional activities. (7) calf muscle group: 1. Anatomical location: calf muscle group can be divided into two parts. The front muscle group includes tibialis anterior and extensor digitorum longus; The posterior muscle group mainly includes triceps surae, flexor digitorum longus and posterior tibial muscle. 2. Start-stop point and function: (1) Start-stop point: tibialis anterior starts from 2/3 of the lateral tibia and ends at the bottom of the medial first cuneiform bone and the first phalanx. The medial and lateral heads of the gastrocnemius muscle of the triceps surae of the leg originate from the medial and lateral epicondyle of the femur respectively, and the soleus muscle originates from the posterior upper part of the tibia and fibula and ends at the calcaneal tubercle. (2) Function: Proximal fixation makes the calf bend and the foot bend; Remote fixation maintains the upright posture of the human body.