Muscle Strain

A muscle strain is an injury that damages the internal structure of the muscle. It may be small, or severe enough to cause internal bleeding and lengthening of muscle fibers. If the damaged parts of the muscle pull away from each other, it is called a muscle rupture.

  • Causes

    A muscle strain is caused by tension or stress applied to the muscle that it cannot withstand. There are several ways that this can happen:

    • Muscle may not be ready for sudden stress
    • Tension may be too much for the muscle to bear, such as lifting a weight that is too heavy for you
    • Muscle is used too much on a certain day

    Certain areas have muscles that are more likely to be strained than others, including:

    • Hamstrings
    • Groin
    • Back
    • Calf

    Muscles that cross two joints are at the greatest
    risk.

  • Definition

    A muscle strain is an injury that damages the internal structure of the muscle. It may be small, or severe enough to cause internal bleeding and lengthening of muscle fibers. If the damaged parts of the muscle pull away from each other, it is called a muscle rupture.

    Muscles of the Back
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  • Diagnosis

    The doctor will ask about your symptoms, your recent physical activity, and how the injury occurred. The injured area will be examined for:

    • Tenderness directly over the muscle
    • Pain when contracting the muscle, particularly against resistance
    • Pain when stretching the affected muscle

    Images may be taken of structures inside your body. This can be done with:

    • MRI scan
    • Ultrasound
    • CT scan

  • Prevention

    To reduce your chance of straining a muscle:

    • Keep your muscles strong so they can absorb the energy of sudden stressful activities.
    • After a short warm-up period, stretch out tight muscles, especially previously injured ones.
    • Learn the proper technique for athletic activities to decrease muscle stress.
    • Stop when you are tired. Tired muscles do not function well. They do not react properly to sudden stress.

  • Risk Factors

    Factors that increase your chances of getting a muscle strain include:

    • Athletic activities, especially those with running, lifting, and jumping
    • Tight muscles
    • Fatigue
    • Overexertion
    • Cold weather

  • Symptoms

    Symptoms depend on how you strained the muscle.

  • Treatment

    Treatment depends on the severity of the strain and the muscle involved.