Your quad muscles are on the front of your thigh. They help you straighten your knee so you can kick, run and jump. But these muscles are prone to injuries such as strains and contusions.
Your quad muscles, or quadriceps femoris, are a group of muscles at the front of your thigh. Together, they contain more mass than any other muscle group in your body. You use your quads to perform a variety of movements, including kicking, running, jumping and walking.
In the past, experts believed there were four quad muscles. In Latin, the root “quad” means “four or fourth.” But recently, they discovered a fifth muscle in this group.
Your quads are vulnerable to injuries, such as contusions (bruising) from blows to the front of your thigh. These muscles also handle a lot of strain from your hip and knee joints, so quad strains or “pulled quads” can occur.
Your quad muscles are skeletal muscles. They’re voluntary muscles, meaning you control how they move and work. Some other muscles in your body, such as those in your heart, are involuntary. This means they work without you having to think about it.
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The main purpose of your quad muscles is to help you straighten your knee. But they also:
Your quad muscles are on the front of your thigh, above your knee and below your hip. Quad tendons attach them to your pelvis, hip bones, femur (thigh bones) and kneecaps.
The five quad muscles are:
All five of these muscles have heads that merge into a single tendon, the quadriceps femoris tendon. This tendon attaches them to the kneecap.
Your quad muscles contain lots of tiny, elastic muscle fibers. These fibers help the muscles contract or tighten. The fibers are red and white, giving muscles a striped appearance.
The most common quad muscle injuries are strains.A strained quad muscle is the result of overstretched muscle fibers. Thigh strains usually affect the rectus femoris since this muscle spans two very mobile joints.
Thigh strains can range from mild to severe:
Other quad muscle injuries include:
Quad muscle injuries aren’t that common. One study of college athletes suggests that thigh strains occur in about 1 out of 10,000 athletes. Hamstring injuries, affecting the muscles at the back of the thigh, tend to be more common.
Quad muscle injuries are common in athletes who run, jump and kick. This includes sprinters and people who play soccer, football, rugby, basketball and softball.
You’re also at risk for quad pain if you:
Take care of your quad muscles by:
Contact your healthcare provider right away if you:
A note from Cleveland Clinic
Your quad muscles play an important role in helping you walk, run, jump and kick. Quad muscle injuries, such as strains or contusions, can prevent you from straightening your knee or bearing weight on your leg. Most mild-to-moderate quad pain gets better with conservative treatments. A severe injury, such as a torn quad muscle, may need surgery.
Last reviewed by a Cleveland Clinic medical professional on 04/21/2022.
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