This factsheet is for people who have strained a muscle, or who would like information about it.
A muscle strain is a stretch or tear in the muscle or tendon caused by over-stretching or over contracting of muscle tissue. The muscles in the legs and lower back are most commonly affected.
- About muscle strain
- Symptoms of muscle strain
- Causes of muscle strain
- Diagnosis of muscle strain
- Treatment of muscle strain
- Prevention of muscle strain
About muscle strain
Muscle strain (also called pulled muscles) occurs when a muscle or the tendon (the tough tissue that attaches it to the bone) is overstretched or torn. Often, muscle strain happens during exercise or sports activities. It can also happen when lifting heavy objects.
Muscle strain often occurs in the legs and lower back. Muscles most likely to be injured include the following.
- Calf muscles – a calf strain is a tear in the muscles at the back of your lower legs. The function of the calf muscles is to help raise the heel.
- Quadriceps muscles – a quadriceps strain is a tear in the muscles at the front of your thigh. The main function of the quadriceps is to help straighten your knee.
- Hamstring muscles – a hamstring strain is a tear in the muscles at the back of your thigh. The main function of the hamstrings is to help bend the knee.
- Paraspinal muscles – a low back strain or lumber strain is a tear in the muscles in your lower back. The main function of the paraspinal muscles is to support your spine as well as the weight of your upper body.
Types of muscle strain
Depending on how severe the injury is, muscle strain may be classed as:
- grade 1 – there is very minor damage to the muscle fibres
- grade 2 – there is a partial tear of the muscle fibres
- grade 3 – there is a complete tear of the muscle fibres
Symptoms of muscle strain
If you have a mild (grade 1) muscle strain, the area may feel tender and the muscle tight. With minor strain, you may be able to carry on with your activity.
More serious muscle strain (grades 2 and 3) will cause considerable pain. The muscle will feel stiff and you will have swelling around the injured area. The pain is worse with movement so it will stop you from doing your activities. You may even have some bruising around the injured area.
If you have a grade 3 muscle strain, you will have severe pain, significant swelling and no muscle function. If you have torn your muscle significantly, there might be an unusual lump or dent that was not previously present over the injured area.
Causes of muscle strain
A muscle strain occurs when the muscle contracts when it is stretched. This can happen when running, jumping or kicking.
You’re more likely to have a muscle strain if your:
- warm-up is too short
- recovery time between training sessions isn’t long enough
- muscles are already tight or stiff
- muscles are tired or overused
- muscles are weak
Diagnosis of muscle strain
Your doctor or a physiotherapist (a health professional who specialises in maintaining and improving movement and mobility) can help diagnose a muscle strain. He or she will determine exactly which muscle tissues are damaged, the extent of the damage and estimate how long the injury will take to heal.
Treatment of muscle strain
Minor muscle strains can be treated quickly and simply at home using the PRICE method.
- Protect your injury from further harm.
- Rest your injury for the first 48 to 72 hours; then re-introduce movement so you don’t lose too much muscle strength.
- Ice packs or a bag of frozen peas wrapped in a towel should be applied to the injured area to reduce swelling and bruising. Don’t apply ice directly to your skin as it can give you an ‘ice burn’ – place a cloth between the ice and skin.
- Compress the area by bandaging it to support the injury and help reduce swelling.
- Elevate the injured area above the level of your heart to control swelling. Keep the area supported. Try to keep it elevated as much as possible until the swelling goes down.
Get medical advice if your injury is very painful and the swelling doesn’t improve.
If your injury is severe, you may need surgery to repair the torn muscle or ligament and then a long period of rest and recovery.
If your injury is severe or you find that it keeps re-occurring, physiotherapy may help to strengthen the damaged muscle or ligament.
Your GP may refer you to a physiotherapist or you can choose to see a physiotherapist privately. He or she will develop a programme of rehabilitation exercises to gradually strengthen and stretch your muscles. These exercises will vary depending on the kind of injury you have and how severe it is. Your physiotherapist may also use various techniques to help speed up the healing of your injury.
The muscle should be allowed to heal fully before you start exercising again.
Prevention of muscle strain
You can reduce your risk of muscle strain by doing a thorough warm-up and cool down before and after exercise. The reason for a warm-up is to allow time for your body to prepare mentally and physically for the exercise that you intend to do. It should include cardiovascular exercise followed by stretching.