Causes of a Quadriceps Strain
Quadriceps muscles are normally injured during vigorous sports activities where there's sudden acceleration and/or explosive jumping (running, track & field, baseball, football), a sudden change of direction and/or strenuous kicking motions (squash, tennis, soccer, karate, kickboxing), or heavy overloading (weightlifting or leg presses on machines). During dynamic activities you often load your hip joint by up to eight times your body weight, which can put a lot of continuous pressure on your quadriceps. Athletes are susceptible to chronic pulls and strains as a result of the repetitive nature of their activities.
Muscle exhaustion and fatigue decrease your strength, power and endurance which increase your risk for injury. Overstretching, overexertion and overuse of your quadriceps muscles occurs frequently in sporting activities and/or daily life. When you have not warmed-up and stretched properly before moving, your muscles aren't ready for the stress, therefore your chances for injury are increased. Doing too much, too soon, too fast, or exercising and moving about in cold weather, puts you at even more risk for quadriceps strains. Sometimes you will get a pulled quadricep doing very simple tasks like jumping off a higher surface, or running after your kids or the bus.
Utilizing a poor technique (under-striding running at full speed then slowing down too quickly), improper equipment (old shoes) or hard and uneven training surface during activities will often put your body at a higher risk for injury. These will also make you feel more tired as the inefficient movements require you to use more energy to complete tasks than required.
Repeated quadriceps injuries are very common. They decrease the function and strength of your quadriceps over time, and encourage inflammation, scar tissue and calcification development, so these damaged parts never heal properly. Impatience and incomplete rehabilitation (not letting injuries heal, so your body can return to peak performance level) is often the reason for repeat injury. This is seen most frequently in runners. Previous injuries to your lower back, pelvis, thighs, hips, knees, and/or calf can also instigate a quadriceps injury (especially if they haven't healed properly).
The above causes are often self-imposed; which means with a little self-management you can have some control over the outcomes. However, the following conditions can make you more prone to quadriceps injuries and are often the cause of a number of the above situations.
Muscle imbalances or weakness in your muscles (especially in your quadriceps and hamstrings, or your lower back and pelvis muscles) can cause strength differences and poor coordination that results in pulled quadriceps muscles. Your quadriceps generally overpower your hamstrings (generally 100:75 ratio), however in some cases your hamstrings can overpower your quadriceps. This is not very common and is seen most frequently with runners. Also, teenage females often have a vastus lateralis muscle that overpowers their weaker vastus medialis muscle. This occurs because their muscles can't keep up with the widening of their hip bones. If no stretching or extra strengthening of the vastus medialis is done, it can result in knee locking, kneecap tracking issues and other knee discomfort.
Tight quadriceps muscles often result from not stretching properly before your activities. However, shortened and tightened muscles, spine stiffness and poor flexibility can be hereditary and/or a side-effect of aging; this is seen more frequently in men than women. All of these can cause a lot of pressure on your body (injured psoas and iliacus which causes weakness in hip flexion, restricts your lower back movement and the femoral nerve) and require a lot of work on your part (daily stretching).
Alignment issues, leg length discrepancies, or overpronation or supination (which affects the way your foot hits the ground when you walk) can put a lot of stress on your quadriceps muscles and result in a pulled quadricep. These often add to the imbalance in your quadriceps and hamstrings.
Other factors that can put extra tension on your quadriceps and influence your risk of experiencing a quadriceps strain include:
- Poor fitness levels and lack of exercise
- Poor nutrition and obesity
- Posture irregularities (lumbar lordosis)
- Neural tension (scar tissue around the nerves)
- Diabetes, gout, rheumatoid arthritis, renal (kidney) failure or bleeding disorders