Calf injuries are known to be quite difficult to manage due to their function and mechanism of injury/re-injury rates. The calf strain/injury is colloquially referred to as “the old person injury”. This is primarily due to the reputation in football where it is typically the older athlete who sustains a calf injury. What is considered ‘old’ when it comes to calf muscle injuries?

Well when we look at the data in elite AFL players, ‘old age’ is considered 25-26 and above. What this means is that the average age for an AFL player suffering their first calf strain is between 25-26. This certainly is not old and it really highlights that calf muscle strains are not just an over 30s injury. So if you have got pain in your calf and are under 30, we recommend you book in for an appointment where we will give a diagnosis and relevant rehabilitation. Older age however, is known to be strong risk factor for sustaining a calf strain. A previous calf muscle injury is also known to be a very strong risk factor for re-injury.

The recurrence rate for calf muscle strains = 14.4-16%, with 54% of re-injuries occurring early after the first injury occurrence (within 2 months). To make the recurrence rate stats more concerning is that 20% of re-injuries occur during the rehabilitation process. These statistics really highlight the importance of seeing the right professional and someone who has the appropriate facilities to help guide you through the process.

Arguably the most important component of calf injury management is the accurate diagnosis of what type of calf strain you have. Calf muscle injuries can be divided into gastrocnemius muscle strains and soleus muscle strains. Interestingly when an AFL player sustained a calf muscle injury, the soleus was affected 85% of the time! However, when an NFL (American football) player sustained a calf injury, the gastrocnemius was affected 86% of the time!

The soleus muscle really is the king of the running athlete. Studies have shown that the soleus muscle can produce up to 8 times body weight of force vertically when running. Whilst the gastrocnemius produces about 3 times body weight of force vertically when we run. The soleus muscle is preferentially activated when the knee is bent, and when we run at a steady state speed (jogging). It is primarily made up of slower twitch muscle fibres, hence it is very important in endurance based running. The gastrocnemius muscle is preferentially activated more at faster paces and when the knee is straighter. It primarily is made up of faster twitch muscle fibres. Identifying the type of calf muscle strain is necessary for appropriate management and returning to sport.

Mechanism of Injury

• 46% of index (initial) calf muscle strains have no inciting mechanism of injury.

• 60% of recurrent calf muscle strain injuries occur during running.

• 45% of soleus injuries have no inciting mechanism of injury.

• Soleus more commonly injured at steady state speeds, with a spike in loading and with a gradual onset of injury.

• Approximately 50% of gastrocnemius injuries occur at high intensity running activities.

• Gastrocnemius also commonly injured in explosive movements like jumping.

Return to Running/Play

• Injuries that were due to a running mechanism take longer to rehabilitate and have a longer return to sport.

• If re-injury occurred, then time loss was further increased!

Calf muscle strains need appropriate management! Even at the elite level, they are known as being unforgiving with how the injury mechanism can be due to low intensity jogging. The rehabilitation involves many intricate steps. Thankfully at The Reform Lab Osteopathy, we are across the research in calf injury management. Additionally, we are a one of a kind clinic that has access to an elite gym space (Project Reform). Therefore, your rehabilitation will not be limited by equipment.