What Muscle Determines a Person's Vertical Jump?

Vertical jumping is an explosive type of exercise often done as part of a plyometric training program. The goal of a vertical jump is, well, to find out how high you can jump. There are a number of muscles throughout your body that determine your vertical jumping ability, but the most vital of these muscles are located in your core and lower-body regions.

Vertical Jumping Science

The power for the vertical jump starts from the ground up. In the first phase of the jump, you have to bend your hips, knees and ankles to lengthen several of your lower body's muscles. This will allow you to to rebound and explode in an upward motion. Your muscles are similar to elastic bands in that they store potential energy when lengthened. A lengthened muscle obviously holds more potential energy than a muscle at rest, so by bending the aforementioned joints, you will be able to jump much higher than if you started from an upright and relaxed position. The more you lower your body before the jump, the higher your resultant jump will be.

Calves and Quadriceps

When you bend your ankles, you are stretching your calves, or more specifically the plantarflexors. These muscles are known as the gastrocnemius and soleus. After the stretching phase, you must extend your ankles to propel yourself off the ground. It's these muscles that first come into play during the jump. After the contraction of the calves, you'll do the same for the quadriceps. This muscle group was lengthened when you bent your knees and thus must contract to extend your knees. The quadriceps is the one of the largest muscles used in the vertical jump, so having strong quadriceps is a predictor for a high jump.

Hamstrings and Glutes

Two other muscles that are determinants of the height of your vertical jump are the hamstrings and glutes. More specifically, it is the biceps femoris, semimembranosus, semitendinosus and gluteus maximus muscles. All of these muscles are lengthened when you bend your hips, thus storing potential energy. When you being to jump up, these muscles will propel your hips forward via hip extension.

Core

Your core plays an immense role in determining how high you can jump. Core refers to the muscles at the center part of your body, vertically speaking. These muscles include the rectus abdominis, transversus abdominis, internal obliques, external obliques and erector spinae. These muscles help stabilize your spine and transfer the power generated from your calves, quadriceps, hamstrings and glute muscles up to your upper body's musculature as you jump.