Vastus Lateralis and Intermedius Exercises

To obtain the strongest and most attractive legs possible, special attention needs to be given to the vastus lateralis and intermedius — the muscles in the middle and outer part of your upper thigh. By targeting these two quadriceps heads with strengthening exercises, you can tone this part of your thighs.

One of four quadriceps heads, the vastus lateralis is the muscle on the outer portion of your thighs. This muscle is visible when your leg is viewed from the front and can either make you or break you in a new pair of shorts.

During squats or leg presses, this muscle is also responsible for keeping your knees from turning inward and buckling together. Vastus intermedius development makes your rectus femoris — the most superficial quadriceps head — more pronounced and improves the appearance of your legs from the side. According to ExRx.net, a toned vastus lateralis can also give the appearance of slimmer hips.

Training your quads with vastus lateralis exercises — such as squats — requires the use of proper form. Set aside some time on leg day to work on your squat technique.

HOW TO DO IT: Stand with your feet slightly wider than hip-width apart. Send your butt backward, as if you are going to sit in a chair. Keeping your back straight, hinge at your hips and bend your knees.

Squat as low as you comfortably can while pushing your knees apart, then stand back up. Keep your chest up throughout the movement.

Read more: Sumo Squat vs. Regular Squat: What's the Difference (and Does It Matter)?

The lever seated leg press offers the advantage of bodily stability, so you can focus on and strengthen the vastus lateralis. When setting up your press, ensure that your lower back is well supported between the seat and back pad.

HOW TO DO IT: Place your feet on the center of the foot plate at shoulder width, then slide them down 1 to 2 inches to properly engage your quadriceps. Tie a resistance band around your knees and during your presses, ensure that your knees maintain tension on the band.

To get the most out of your vastus intermedius, train one leg at a time. Using only one leg requires the intermedius to support and stabilize the entire leg, activating as much of the head as possible.

Depending on your level of training, beginners can start with a body-weighted walking lunge while more advanced trainers can move on to single leg splits or the barbell lunge.

Read more: What Muscles Does the Leg Curl/Extension Machine Work?

Many people have a strength imbalance in their quadriceps — with the vastus lateralis overpowering the vastus medialis. This causes the kneecap to track improperly during squats, which can lead to a painful condition called patellofemoral pain syndrome. Limit your vastus lateralis exercises and consult a physical therapist for exercise instruction if you have this condition.