Rectus femoris muscles/大腿直筋の筋肉(Daitaichokkin no kin'niku)/直肌肌肉(Zhí jī jīròu)

A muscle with origin from the ilium and the acetabulum, with insertion into a tendon of the quadriceps muscle of the thigh.

The rectus femoris muscle is one of the four muscles that makes up the quadriceps muscle.

The muscle runs up the middle of the thigh, connecting from the knee to the hipbone. The 

rectus femoris is responsible for straightening the leg and for lifting the leg toward your 

chest. When you work this muscle, you not only tone the thighs, you also add stability to the 

knee and hip joint.

Walking Lunges

Lying Leg Raise

Resistance Band Squats

Jump Squat

Walking lunges target the rectus femoris by elongating and strengthening the muscle. Begin 


by standing at one end of a room. Step forward with your right foot, bending your legs at the 


knee, to sink into a lunge position -- do not let the knee extend over the ankle. Push off with 


your left foot to move forward and meet your other foot. Now lead with the left foot to lunge 


forward. Continue to lunge across the room until you reach the opposite end. To increase the 


difficulty of this exercise, you can hold a weighted bar on your shoulders or dumbbells in 


your hands.

While the lying leg raise works your abdominal muscles, it also targets the rectus femoris as a dynamic stabilizer -- meaning it helps to strengthen the muscles in a different manner than traditional quadriceps exercises. Perform this by lying on your back on a weight bench with your arms over your head, grasping the bench for support. Straighten your legs, letting them hang slightly off the bench. You should feel your abdominal muscles working. Slowly pull your knees in toward your chest to work the rectus femoris muscles. Hold this position for two seconds, then extend the legs. Repeat nine times to make a set of 10. Rest for 30 seconds, then repeat for one to two additional sets.

Adding a resistance band to the traditional squat exercise helps to challenge the rectus femoris in different ways. Begin by stepping on a resistance band, holding an end in each hand. Pull the band tightly enough to where you experience resistance when standing -- you may need to fold your arms in toward your chest. Bend your knees to lower your buttocks toward the ground. Stop when your thighs are parallel to the floor. Straighten the knees to return to your starting position, feeling the resistance band challenging your movements. Repeat the squat 10 times. Rest for 30 seconds, then repeat for one to two additional sets.

The jump squat challenges the fast-twitch muscle fibers in your rectus femoris, helping you to experience muscle gains more quickly. To perform, stand with your feet hip-width apart. Squat down, and jump in the air as high as you can. Land softly on the balls of your feet first and then squat down slightly. To increase the difficulty of the exercise, try to jump between 1 and 2 feet ahead of you. Repeat the jump eight times. Perform two additional sets.