A muscle strain (pulled muscle) is an overstretch or tear in your muscle fibres. It can happen if you overstretch your muscle or you put too much force on it. You’re most likely to strain a muscle in your legs or back.
A muscle strain is an injury to a muscle or a tendon — the fibrous tissue that connects muscles to bones. Minor injuries may only overstretch a muscle or tendon, while more severe injuries may involve partial or complete tears in these tissues.
Sometimes called pulled muscles, strains commonly occur in the lower back and in the muscles at the back of the thigh (hamstrings).
Muscle strain occurs when a muscle becomes overstretched or works too hard. People can often treat muscle strains at home and use specific exercises to speed up their recovery.
Muscle strains vary in severity depending on how much damage the muscle fibers sustain. Strains range from mild overexertion to a partial or complete tear of the muscle.
The difference between a strain and a sprain is that a strain involves an injury to a muscle or to the band of tissue that attaches a muscle to a bone, while a sprain injures the bands of tissue that connect two bones together.
A strain to the muscle or muscle tendon is the equivalent of a sprain to ligaments. A muscle strain occurs when muscle fibers cannot cope with the demands placed on them by exercise overload and leads to tearing of the fibers. It is a contraction-induced injury in which muscle fibers tear due to extensive mechanical stress. This mostly occurs as a result of a powerful eccentric contraction or over-stretching of the muscle. Therefore, it is typical for non-contact sports with dynamic characteristics such as sprinting and jumping.
What is Muscle Strain?
A muscle strain is the stretching or tearing of muscle fibers. Most muscle strains happen for one of two reasons: either the muscle has been stretched beyond its limits or it has been forced to contract too strongly. In mild cases, only a few muscle fibers are stretched or torn, and the muscle remains intact and strong. In severe cases, however, the strained muscle may be torn and unable to function properly. To help simplify diagnosis and treatment, doctors often classify muscle strains into three grades, depending on the severity of muscle fiber damage:
- Grade I strain. In this mild strain, only a few muscle fibers are stretched or torn. Although the injured muscle is tender and painful, it has normal strength.
- Grade II strain. This is a moderate strain, with a greater number of injured fibers and more severe muscle pain and tenderness. There is also mild swelling, noticeable loss of strength and sometimes a bruise.
- Grade III strain. This strain tears the muscle all the way through, sometimes causing a “pop” sensation as the muscle rips into two separate pieces or shears away from its tendon. Grade III strains are serious injuries that cause complete loss of muscle function, as well as considerable pain, swelling, tenderness and discoloration. Because Grade III strains usually cause a sharp break in the normal outline of the muscle, there may be an obvious “dent” or “gap” under the skin where the ripped pieces of muscle have come apart.
Grading Of Muscle Strains
Physiotherapists grade muscle strains depending on how bad they are. Strains within each grade may also vary in how mild or severe they are.
Grade one strain
This causes slight damage to your muscle fibres.
Your muscle may feel tender.
You may have a bit of pain too.
You should still have normal strength in your muscle, but you may find it too painful to carry on with your usual activities.
Grade two strain
This is a partial tear of your muscle (part of the way through it). Grade two strains can also vary from milder strains to more severe ones.
Your muscle is likely to be painful.
You may have a noticeable bruise and swelling over the affected area.
You’ll probably lose some strength in the muscle too, stopping you from carrying on with your usual activities.
Grade three strain
This is a full tear of your muscle (all the way through it).
Your muscle is usually really painful.
You’ll have a lot of swelling and bruising.
You may have a lump at either end of your muscle.
You may feel a popping sensation when you hurt your muscle.
You may lose all strength in your muscle so you can’t use it – if it’s a leg muscle, you probably won’t be able to walk on it.
You won’t be able to carry on with your usual activities.
This grading can help your physiotherapist to choose the right treatment for you.
Symptoms Of Muscle Strain
- sudden pain that worsens while contracting the strained muscle
- swelling and bruising
- loss of strength and range of motion
When muscle is initially injured, significant inflammation and swelling occurs. Patients often report the sensation of pain as the feeling of being “stabbed.”
After this inflammatory phase, the muscle begins to heal by regenerating muscle fibers from stem cells that live around the area of injury. However, a significant amount of scar tissue also forms where the muscle was injured. Over time, this scar tissue remodels, but the muscle tissue never fully regenerates. It is thought that this makes a strained muscle prone to future injury.
In a mild strain, a torn muscle may feel slightly stiff, but still flexible enough for use. A severe muscle strain is when the muscle is severely torn. This results in pain and very limited movement.
The symptoms of mild to moderate muscle strains usually go away within a few weeks. More severe strains may take months to heal.
Causes Of Muscle Strains
An acute muscle strain is when your muscle tears suddenly and unexpectedly. Such tears can occur either from injuries or trauma. This can be due to:
- not warming up properly before physical activity
- poor flexibility
- poor conditioning
- overexertion and fatigue
There’s a misconception that only rigorous exercises and workouts of high intensity cause muscle strains. According to Johns Hopkins Medicine, muscle strains can even occur from walking.
An acute strain can happen when you:
- slip or lose your footing
- throw something
- lift something heavy
- lift something while in you’re in an awkward position
Acute muscle strains are also more common in cold weather. This is because muscles are stiffer in lower temperatures. It’s important to take extra time to warm up in these conditions to prevent strains.
Chronic muscle strains are the result of repetitive movement. This can be due to:
- sports like rowing, tennis, golf, or baseball
- holding your back or neck in an awkward position for long periods of time, such as when you work at a desk
- poor posture
If a doctor suspects a muscle strain, they will perform a physical examination and ask a person about their symptom history. They may also order imaging studies, such as X-rays, to make sure that the bone has not broken.
As part of the diagnosis, a doctor will usually designate the injury as a grade 1, 2, or 3 strain. A grade 1 strain is mild and should heal quickly, while a grade 3 strain is a severe muscle tear.
An X-ray may be helpful to rule out a fracture or dislocation as the cause of pain. Occasionally in young athletes, the tendon can pull off a piece of bone where it attaches, which can be seen on X-rays.
However, pure muscle injuries cannot be seen on regular X-rays. An MRI can sometimes be helpful to determine where the injury has occurred and whether there is complete rupture or not. MRIs can also show collections of blood, called a hematoma, that sometimes occur following severe injuries.
You’ll usually know if you’ve strained a muscle after an activity, as you’ll feel pain straightaway or shortly afterwards. If so, you probably don’t need to see a healthcare professional and you can manage your symptoms at home yourself. But if you’re not sure what’s caused your symptoms, or they’re very bad or not getting better, contact a physiotherapist or your GP. There are lots of different ways to access physiotherapy – you may be able to refer yourself directly.
A physiotherapist or GP will usually be able to diagnose a muscle strain (pulled muscle) just by examining you and asking questions. They’ll ask you about your symptoms and medical history. They’ll also ask how you hurt yourself.
Not everyone will have further tests, but if your injury is very bad or the cause isn’t clear, you may need to have some. Your physiotherapist or GP may arrange for you to have an ultrasound or a magnetic resonance imaging (MRI) scan. An ultrasound uses sound waves to create an image of the inside of your body and an MRI scan uses magnets and radio waves.
If you have symptoms of a grade three strain, you should go to your local accident and emergency (A&E) immediately.
First Aid For Muscle Strains
Most muscle strains can be successfully treated at home. According to the Mayo Clinic, minor muscle strains can be treated with rest, ice, compression, and elevation (RICE).
Avoid using your muscle for a few days, especially if movement causes an increase in pain. But too much rest can cause muscles to become weak. This can prolong the healing process. After two days, slowly begin using the affected muscle group, taking care not to overdo it.
Apply ice immediately after injuring your muscle. This will minimize swelling. Don’t put ice directly on your skin. Use an ice pack or wrap ice in a towel. Keep the ice on your muscle for about 20 minutes. Repeat every hour on the first day. For the next several days, apply ice every four hours.
To reduce swelling, wrap the affected area with an elastic bandage until swelling comes down. Be careful not to wrap the area too tightly. Doing so can reduce your blood circulation.
Muscle Strain Treatment
Even if a person’s muscle strain does not require medical attention, it is important to rest the muscle and allow time for recovery. A strained muscle is more susceptible to re-injury.
Several home treatments can help promote muscle healing. One of the most effective approaches to muscle strain recovery is the RICE technique.
RICE stands for:
- Rest: Resting the injured muscle gives the body time to repair.
- Ice: Applying a cloth-covered ice pack to the damaged muscle for 10 to 15 minutes at a time can help reduce swelling and inflammation.
- Compression: If possible, apply a compression bandage to reduce swelling. People can use cloth or elastic bandages from drug stores or online stores to wrap up an injured foot, ankle, leg, wrist, or arm.
- Elevation: Elevating an injured arm or leg can help reduce swelling and allow fluid to flow back toward the heart.
In addition to using the RICE method, a person can take medication to control pain and reduce swelling or inflammation.
Over-the-counter (OTC) nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen and naproxen, reduce both pain and inflammation. Acetaminophen can relieve pain, but it does not have the anti-inflammatory properties of NSAIDs.
Physiotherapy For Muscle Strain
If your injury is very bad or it keeps coming back, physiotherapy may help to strengthen your damaged muscle.
Your GP may refer you to a physiotherapist or you can book an appointment with a physiotherapist yourself. You can also choose to see a physiotherapist privately.
The physiotherapist will create a programme of exercises to gradually strengthen and stretch your muscles. These exercises will depend on the type of injury you have and how bad it is.
Surgery And Platelet-Rich Plasma Injections
Complete muscle injuries can lead to significant functional impairment and lost playing time and may require surgical repair. This is especially the case for patients who need to be able to run or be sufficiently agile to participate in sport. Platelet-rich plasma (PRP) injections may be able to help accelerate the regeneration of damaged muscle tissue.
If your muscle strain is very bad, or you have a completely torn muscle, you may need an operation to repair it. Your GP will arrange for you to see an orthopaedic surgeon who will explain which type of procedure you need. You’re most likely to be referred if:
- you’re not recovering as quickly as you should be
- your symptoms are getting worse
- you’re getting new symptoms
- your symptoms are worse than they should be for your type of injury
The type of operation you need will depend on the location of the tear and muscle involved.
You’ll probably need to see a physiotherapist after your surgery to get back to normal.
How To Prevent Muscle Strains
People may be able to prevent muscle strains by warming up the muscles before doing physical activity and by avoiding overstretching the muscles.
You can decrease your chances of straining a muscle if you take some basic precautions:
- Try not to sit in one position for too long. Take frequent breaks to move and change position. Use a chair that provides good support for your lower back, or use a pillow for support. Try to keep your knees level with your hips.
- Maintain good posture when standing and sitting. If you spend a long time in one position, try to alternate putting one foot and then the other on a low footstool. This can help decrease stress on your back muscles.
- Lift objects carefully. Keep your back straight, bend at the knees, and always lift with your legs. Hold the weight close to your body. Don’t lift and twist at the same time.
- Take precautions to prevent falls, such as holding handrails on stairways, avoiding slippery surfaces, and keeping your floors uncluttered.
- Lose weight if you’re overweight.
- Wear shoes that fit properly.
- Warm up your muscles thoroughly first – do some gentle exercise to get your body ready for more vigorous activity.
- Cool down properly afterwards – gradually decrease your activity levels until your breathing and heart rate return to normal.
- Do some gentle stretches while your muscles are still warm.
- Use the correct exercise or sports equipment.
- Wear properly fitting sports shoes – and the right shoes for your activity.
- Replace your shoes when they wear out.
- Avoid exercising when you’re tired or in pain.
- Have regular days off exercise between training sessions.
Regular exercise can keep your muscles healthy and strong, but proper techniques are also crucial in preventing muscle strains. Always stretch and warm up before engaging in physical activity.
Similarly, take the time to stretch after each workout or session of physical activity to prevent muscle stiffness. If you’re new to exercising, start slowly. Build up your activity a little at a time.
It’s vital that you understand your body’s limitations. If something doesn’t feel right during an activity, stop immediately.
Some people may benefit from working with a physical therapist or a strength and conditioning professional to help improve their exercise technique and allow them to build strength and flexibility safely.