Structural Muscle Injuries

Invigorate Health and Performance, Structural muscle injuries

Muscle injuries occur when the amount of forced being applied to the muscle exceeds its ability to withstand the force. This can occur:

  • When a muscle is stretched beyond its capacity to lengthen (e.g. over stretching) OR
  • When the muscle is not strong enough to handle a force being applied to it (accelerating or decelerating suddenly)

Clinically, muscle injuries are classified into three separate categories. These injuries are categorised in accordance with how severe the muscle damage is. They are graded as followed:

  • Grade I: This is only a mild tear where only a few muscle fibres are stretched and/or torn. Although, the muscle will feel sore and tender, it generally maintains full strength.
  • Grade II: This is a moderate tear. A grade II has a greater number of fibres which are damaged and is more painful and tender. Mild swelling is also present along with a noticeable loss of strength and often comes with a bruise.
  • Grade III: This is a severe tear. A grade III muscle injury is when the muscle ruptures all the way through. This can sometimes cause a “popping” sensation as the muscle tears into 2 separate pieces or shears away from its tendon. Grade II tears cause complete loss of muscle function along with serious pain, swelling and discolouration (bruising). Grade II muscles can often present with an obvious “dent” under the skin where the muscle has torn and come apart. In some cases, these tears require surgery.

Muscular tears are generally quite painful injuries and recovery is very different for every person. The table below gives you a brief guide to the symptoms and prognosis related to the different grades of injury.

Grade I Grade II Grade III




Mild pain and tenderness.

Normal strength.


Moderate tear.

Loss of strength.

Mild swelling/bruising.


Severe pain and tenderness.

“Pop” sensation.

Considerable swelling.

Severe bruising.

“Dent” in the muscle.




3-4 weeks


6-8 weeks


12-16 weeks

Physiotherapy is an essential part of the recovery following a muscular injury. Your physiotherapist will take you through a program that runs you through pain relief, regaining mobility and strength in the injured muscle, then will help you return to sport.

If you have any questions, or need some help with your muscular injury. Please reach out, we would love to help.

Written by Nicholas Dimos (Physiotherapist)