Muscle injuries can occur in three main types: contusions caused by impact, strains caused by intense muscle contraction, and elongations caused by overstretching a muscle beyond its capacity.

1. Muscle Injuries
There are three main types of muscle injuries.

2. Contusions
Caused by impact to a muscle, a quadricep for example:

3. Strain
Caused by
intense, rapid
contraction.

4. Elongation
Caused when a muscle is stretched beyond its capacity.