What is the vastus intermedius muscle?
The vastus intermedius muscle is a muscle located in the thigh that is part of the quadriceps femoris muscle group. It originates on the front and lateral aspects of the femur, and inserts on the patella and the quadriceps tendon. Its main function is to extend the knee joint. It works in conjunction with the other muscles in the quadriceps group (vastus lateralis, vastus medialis, and rectus femoris) to extend the knee and straighten the leg. (1)
Origin, insertion and function
Origin:
The vastus intermedius muscle originates on the front and lateral aspects of the femur.
Insertion:
It inserts on the patella and the quadriceps tendon.
Function:
The main function of the vastus intermedius muscle is to extend the knee joint. It also helps to stabilize the patella during knee movement.
Common signs of a weak vastus intermedius muscle
Common signs of a weak vastus intermedius muscle may include:
- Knee pain or discomfort when walking, running, or climbing stairs
- Difficulty in straightening the knee fully
- A tendency for the knee to give way or buckle during physical activity
- An uneven or asymmetrical muscle appearance in the thigh
- Difficulty in performing exercises that involve knee extension, such as leg press or squats
- Weakness or fatigue in the thigh during physical activity
- Difficulty in maintaining proper form during exercises that engage the quadriceps, such as lunges or step-ups.
Exercises that strengthen the vastus intermedius
Exercises that can help make the vastus intermedius stronger include:
Quadriceps exercises:
Squats:
- Stand with your feet hip-width apart and your toes pointing forward. Lower your hips back and down as if sitting back into a chair, keeping your weight in your heels and your back straight. Push through your heels to stand back up.
Leg press:
- Sit in a leg press machine and place your feet hip-width apart on the platform. Slowly press the platform away from you using your quadriceps.
Lunges:
- Step forward with one foot and bend your knees to lower your body. Keep your front knee behind your toes. Push through your front heel to stand back up.
Isolation exercises:
Leg extensions:
- Sit on a leg extension machine and place your feet behind the ankle pad. Slowly extend your legs by pushing the pad away from you.
Patellar tendon exercise:
- Sit on a bench and place a band or cable around your ankle. Slowly straighten your knee, pushing against the resistance provided by the band or cable.
It’s important to note that proper form and technique are crucial when performing these exercises to avoid injury and to effectively target the vastus intermedius muscle. Also, it’s important to add variety to your exercise routine and work on other muscle groups as well. It’s always a good idea to consult a personal trainer or a physical therapist to help you design an exercise plan that fits your needs and goals.
References:
- Wikipedia contributors. (2020, October 20). Vastus intermedius muscle. Wikipedia. https://en.wikipedia.org/wiki/Vastus_intermedius_muscle