What happens when you tear your calf muscle?
A muscle tear happens when the fibres, which make up the muscle belly, are overloaded and can't cope with the levels of stress, and so tear as a result. This typically occurs when exercising, due to either overstretching of the muscle or a powerful contraction.
Calf tears are a common injury and happen in sports where there are changes in load, be it accelerating or decelerating, or changes in volumes (like distances, frequency of training or intensities). This is why running is one of the most common causes of a calf injury. Calf muscle tears also occur most frequently in middle-aged, physically active people.
Calf muscle anatomy
The calf musculature is located at the back of the lower leg, and is comprised of three muscles which form the triceps surae. These muscles are: the gastrocnemius, which is made up of two muscle heads and is the most superficial and the largest part of the calf; the soleus, which lies underneath; and the smallest, which is called plantaris.
These muscles together insert into the heel (see image below) and form the Achilles tendon. The main movement the calf is responsible for is planter flexion of the ankle (pointing the toe). The gastrocnemius is a bi-articular muscle, which means it spans over two joints, the ankle and the knee. Because of this, it's the most common part of the calf to get injured, specifically the medial (inside) aspect.
Bi-articular muscles are particularly prone to tears, as they're put under increased stresses due to changes in muscle length and muscular contractions, while also having to cope with the high levels of internal forces. The gastrocnemius is most commonly damaged when the ankle is dorsiflexed (toes up) and the knee is bent. This is because it tries to contract in an already lengthened position where there's an eccentric force (a force causing rotational movement) occurring. Most muscle strains occur under eccentric loads.
What are they symptoms of a calf muscle tear injury?
Symptoms of a calf injury are usually a sharp pain, followed by swelling or bruising. There might be a stabbing or tearing sensation felt at the time of injury, and there may be pain, tightness or discomfort when weight bearing. Pain will be localised to the tear region and may be painful under load or stretch. Depending on the grade of injury you may be able to continue to activity or it may be too painful.
How to treat a calf muscle tear
Calf tears are usually managed conservatively and rarely need surgery. Only in the instances of a rupture is surgical intervention required. Conservative management includes protect, rest, ice, elevation, and compression (PRICE). A graded, supervised exercise programme is essential in conservative management for the fastest recovery times and is most suitable for grade one and two tears. Physiotherapy treatment is usually the most common method where they focus on reducing pain and improving strength, range of motion, flexibility and quality of the tissue.
How long does a calf muscle tear take to heal?
Muscle tears are categorised into three grades, similar to a ligament injury:
Grade one is classed as a 'mild' strain. In this situation, only a small number of muscle fibres are affected. Strength output is unaffected and full range of motion is maintained. Return to sport is usually 1-3 weeks.
Grade two is 'moderate' in terms of severity. In this situation, nearly 50% of the muscle fibres are torn. There will be minor decreases in strength outputs and it's usually accompanied with swelling and acute pain. Return to sport is usually 3-6 weeks.
Grade three is a full rupture of the muscle. This can either be the muscle belly being split in two, or the tendon separating from the muscle belly. Bruising and swelling are typically present and there will usually be a complete loss in strength outputs and severe pain. Grade one and two muscle injuries are the most common in running, with grade three being the least. Return to sport is typically around 6 months.
How to start training again after a calf muscle injury
After injury a gradual return to your running programme is essential. Sometimes swimming or cycling can help, even before you feel ready to run. Wait for your physiotherapist to give you the all clear to start running and then slowly increase. Start with a light jog, 10-15mins in duration, preferably on a flat surface. There may be some slight tightness, pain or discomfort initially, but don’t be alarmed as this is to be expected. Providing the pain stays mild to moderate (below a 4/10 on the pain threshold) then it can be pushed through.
The more the activity is done, the more your body will adapt and the more the discomfort will lesson. Never push through pain that's moderate to severe (6+/10), however, as this will only flare up your nervous system and could potentially lead to re-injury. Once symptoms and confidence start to improve, you can increase running duration and start to add in hills.
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How to prevent a calf muscle injury
The best way to prevent calf muscle tears is to always progress your training slowly and minimise overload as much as possible. Warming up before and after exercise is also valuable. Make sure you have adequate lower-limb strength and conditioning, including flexibility, to help support you through your training and events. Having good footwear is also always essential, and sometimes undervalued.
If you're worried about any kind of soft tissue injury it's best to seek medical advice and get it checked out by a physiotherapist. James Ticehurst is a chartered physiotherapist with Capital Physio and has a passion for treating sports and musculoskeletal conditions. Capital Physio have clinics in London, Manchester, Birmingham, Cambridge, and North Lincolnshire.