Medically Reviewed By William C. Lloyd III, MD, FACS

What is a strain?

A strain is an injury to a muscle, tendon, or a connected group of muscles and tendons. Strains are sometimes confused with sprains because they have similar symptoms. However, sprains are a different type of injury. While strains affect muscles and tendons, sprains affect ligaments. Ligaments are the bands of tissue that connect bones at the joints.

To understand strains, it helps to understand your body’s muscles. There are three types of muscles in your body:

  • Involuntary cardiac muscle, or myocardium, is your heart muscle.

  • Involuntary smooth muscles are the muscles of organs, such as your stomach and intestines.

  • Voluntary skeletal muscles are muscles that attach to bone.

Voluntary skeletal muscles are the type of muscle that you can strain. They help support your body’s skeletal structure and work together with tendons to enable movement. Tendons are strong cords of soft connective tissue that attach bones to muscles. Strains arise from a mechanical deformation of the affected tissues, meaning tissue is physically stretched to an extreme or torn.

Muscles in the neck, back and legs are most susceptible to strain. However, other muscle areas can be strained, including those in the groin, feet, ankles, arms and hands. Other names for a strained muscle include muscle strain or pulled muscle. Strains can range in severity from a mild stretch or pull to a complete tear and rupture of the muscle or tendon. Symptoms of a strained muscle include muscle weakness, pain, spasms, swelling, cramping, or loss of muscle function.

Strains can be chronic (developing slowly over time) or acute (occurring suddenly). Chronic strains are the result of repetitive overuse of muscles. Acute strains are the result of immediate muscle overload. Typical activities that cause strains include sports and other exercise activities; accidents, such as falling or slipping; heavy lifting and other strenuous activities; and repetitive use of muscles, such as shoveling snow during the course of winter.

Rest, ice, compression, elevation, and nonsteroidal anti-inflammatory drugs (NSAIDs) help relieve the aches and pains of a mild muscle strain. Often, this is the only muscle strain treatment necessary for mild cases. Moderate to severe strains may require more extensive treatment, such as surgery, immobilization, and physical therapy. Muscle strain recovery time depends on the extent of the injury.

In some cases, muscle strains can be serious. Seek immediate medical care (call 911) if you, or someone you are with, have serious symptoms of a severe muscle strain, rupture or tear. These symptoms may include hearing a popping sound when you are injured; severe, disabling pain or swelling; and inability to use the muscle, such as an inability to walk.

What are the symptoms of a strain?

The symptoms of a strain can range from mild to severe, depending on the type and extent of the strain. Chronic strains are the result of prolonged, repetitive overuse of muscles. It is easy to overlook the symptoms of a chronic strain because they develop over time.

Acute strains are the result of immediate muscle overload from overstretching, excessive muscle contraction without adequate breaks, and trauma. Acute strains tend to have more severe and noticeable symptoms than chronic strains. However, both types of strain can cause these similar symptoms:

  • Bruising
  • Limited range of motion
  • Loss of muscle function
  • Muscle cramping or spasms
  • Muscle pain or weakness
  • Swelling

Symptoms that might indicate a serious condition

In some cases, muscle strains can be serious. Seek immediate medical care (call 911) if you, or someone you are with, have serious symptoms of a severe muscle strain, rupture or tear including:

  • Hearing a popping sound when you are injured
  • Inability to use the muscle, such as an inability to walk
  • Severe swelling
  • Severe, disabling pain

What causes a strain?

A strain occurs when a muscle or tendon is pulled, stretched, twisted or torn. There are two different types of strain, chronic and acute. Chronic and acute strains have different causes.

Causes of chronic strain

Chronic strains happen slowly over time from prolonged, repetitive overuse of muscles. Chronic strains develop from using the same muscle groups in the same pattern, causing even small stresses to build on one another. Causes of chronic muscle strain include:

  • Improper body mechanics or using the wrong muscle groups for a task, such as repeatedly lifting heavy objects using your back instead of your legs

  • Improper sports mechanics or techniques, such as habitually gripping a tennis racket too tightly or an incorrect golf swing

  • Participation in the same exercises in the same way, day after day

  • Poor posture

  • Use of the wrong equipment, such as running shoes without the proper support for your foot type

Causes of acute strain

Acute strains occur suddenly due to immediate muscle overload. Causes of acute strain include:

  • Direct blow to the muscle, such as getting hit by a baseball or a lacrosse stick

  • Excessive muscle contraction, such as sprinting during a race or running bases

  • Overstretching, such as sudden movement of cold muscles without proper warm up or stretching

  • Trauma or injury, such as slipping and falling or a rear-end car accident, which can cause muscle strain in the neck (whiplash)

What are the risk factors for a strain?

A number of factors increase the risk of developing strains including:

  • History of previous strain injury

  • Muscle fatigue from overuse or underuse

  • Muscle imbalance in which one group of muscles overcompensates for another group

  • Muscle tightness from not warming up or stretching properly before and after sports or other strenuous activities

  • Participation in certain activities, especially sports, such as football, basketball, soccer, running, dancing, and skiing, and any activity that involves frequently moving or lifting heavy objects

  • Poor conditioning

How do you reduce your risk of a muscle strain?

You may be able to lower your risk of developing a strain by:

  • Achieving and maintaining appropriate physical conditioning, flexibility, and muscle strength

  • Avoiding sports or heavy lifting when your muscles are already fatigued or weakened

  • Cross-training with a variety of sports activities

  • Eating a balanced diet

  • Maintaining a healthy weight

  • Preventing slips and falls with appropriate safety measure

  • Stretching and warming up before any sports activity or other strenuous activity

  • Wearing a seat belt and adjusting the headrest properly when traveling in any vehicle

  • Wearing appropriate protective equipment when participating in sports or when lifting and moving heavy objects

  • Wearing footwear that fits properly and is not worn out

When should you see a doctor for a strain?

In most cases, you can manage a mild strain at home with self-care treatments. If pain or discomfort continues for more than a couple of weeks despite home treatment, make an appointment with your doctor.

See your doctor promptly when:

  • Pain occurs with numbness or tingling

  • Pain or discomfort is intense or unbearable

  • Pain or discomfort worsens

Call 911 or go to your nearest emergency room for any of the following potentially serious symptoms:

  • Hearing a popping or snapping sound during an injury

  • Loss of muscle function or inability to use the muscle at all

  • Severe pain or swelling

  • Uncontrollable bleeding with the injury

How do doctors diagnose the cause of a strain?

To diagnose your condition, your doctor will perform a physical exam. The exam will check for swelling, tenderness, and the location of your pain. Depending on where the strain is, your doctor may also check the range of motion of a related joint. In some cases, your doctor may be able to feel problems with the muscle or tendon.

Your doctor may also ask you several questions about your injury including:

  • When and how did your pain or discomfort start?

  • Did you experience an injury? How were you moving during the injury?

  • Did you hear anything during the injury, such as a pop or snap?

  • On a scale of 1 to 10, with 10 being the worst pain ever, how would you rate your pain?

  • Are you experiencing any other symptoms, such as numbness or tingling?

  • What, if anything, makes your pain or discomfort better or worse?

  • What treatments have you tried?

  • Have you had this type of injury or injured this body part before?

After taking your medical history and exam, your doctor may order imaging exams, including X-rays, ultrasounds, or MRIs (magnetic resonance imaging). These exams can help your doctor rule out a fracture and tell what kind of injury you have and its severity. This information lets your doctor grade the strain:

  • Grade 1: mild damage that usually heals readily

  • Grade 2: extensive damage with loss of strength and motion that usually takes 2 to 3 months to heal

  • Grade 3: complete tear or rupture with a palpable defect that may require surgery and takes several months to heal

It is not always possible to diagnose an underlying cause or condition. If the problem persists and your provider is unable to determine a cause, seeking a second opinion may give you more information and answers.

How do you treat a strain?

Mild to moderate muscle strains frequently heal on their own with proper home treatment including:

  • Nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen (Advil, Motrin) and naproxen (Aleve, Naprosyn). NSAIDs reduce swelling and relieve pain and soreness.

  • RICE, an acronym that stands for rest, ice, compression, and elevation of the strained area. Talk with your healthcare provider before using compression bandages to ensure safe use.

  • Therapeutic exercises to alleviate pain and restore range of motion

Physical therapy can be helpful for moderate strains. It focuses on helping you strengthen and stabilize the muscles.

More serious strains, such as a muscle tear or rupture, may require surgical repair, immobilization, and regular physical therapy.

What are the potential complications of a strain?

Mild to moderate muscle strains usually respond to rest, ice, and over-the-counter anti-inflammatory medications. Serious strains or strains that are not properly treated can lead to serious complications including:

  • Chronic pain

  • Disability

  • Loss of mobility

  • Permanent damage to the muscle or tendon involved

  • Permanent limited range of motion

  • Poor quality of life

  • Weakness

It is important to contact your healthcare provider when you experience muscle pain, soreness or weakness for proper diagnosis. Following the treatment plan you and your healthcare provider develop specifically for you will minimize the risk of complications and help restore your mobility.

Was this helpful?
  1. Hamstring Muscle Injuries. American Academy of Orthopaedic Surgeons.
  2. Muscle Strain. Hospital for Special Surgery.
  3. Muscle Strains. Mayo Foundation for Medical Education and Research.
  4. Muscle Strains in the Thigh. American Academy of Orthopaedic Surgeons.
  5. Sprains and Strains. National Institute of Arthritis and Musculoskeletal and Skin Diseases.
  6. Sprains, Strains, and Other Soft-Tissue Injuries. American Academy of Orthopaedic Surgeons.
  7. Strains. MedlinePlus, National Library of Medicine, National Institutes of Health.
Medical Reviewer: William C. Lloyd III, MD, FACS
Last Review Date: 2021 May 19
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