The dreaded muscle strain – it’s painful during strength training, and stretching only alleviates it for a short while. Do you book in with your physio or do you wait and hope the pain goes away over the next few days?
How Do Strains Happen?
Muscle strains make up to 55% of all sports injuries, and are the most frequent cause of physical incapacity in sports practice. Muscle strains occur when the force exerted on a muscle generates greater stress than the muscle can withstand, which leads to excessive stretching of the muscle fibres and consequently a tear close to the muscle-tendon junction (also known as the myotendinous junction).
Symptoms of Muscle Strain
Common symptoms of a strained muscle are:
- Localised pain and/or tenderness
- Possible bruising
- Weakness
- Muscle tightness that is not improved with stretching
| Classification | Fibers Torn (%) | Pain / Inflammation | Functional Deficits | Recovery Time |
| Grade I (mild) | Mild tear, < 5% | Minimal swellingDelayed pain and/or tenderness | Minimal-no loss of strength or function | 7-21 days |
| Grade II (moderate) | Partial tear, ~50% | Significant pain and associated swelling | Evident decrease in strength and function | 2-3 months |
| Grade III (severe) | Complete rupture 100% | Severe swelling and pain | Complete loss of strength and function | > 6 months (with possible surgery) |
Should I Rest or Stretch?
During the acute phase (first 2 weeks of injury), apply the PRICE principle: Protect, Rest, Ice, Compress and Elevate.
Protect – stop training the strained muscle immediately
Rest — Rest the injured limb to prevent muscle retraction (formation of a larger muscle gap) and reduce the subsequent size of connective scar tissue
Ice and Compress – Early use of cryotherapy is associated with reduced inflammation and accelerated regeneration. Current research recommends a combination of ice and compression over 15-20 minutes, with repetitions at intervals of 30-60 minutes.
Elevate – Elevate the limb above the level of your heart to reduce hydrostatic pressure, to diminish the accumulation of liquid in the interstitial space and hence reducing swelling.
Do not stretch the injured muscle during the acute phase. Since we know that strains occur from loading muscle fibres beyond their capacity causing excessive stretch, stretching the muscle repeats the mechanism of injury and increases the potential to further damage an already weakened muscle.
Rehab after Muscle Strain
Acute stage
- Isometric strength training (pain-free) for the affected muscle
- Continue strength training for unaffected limbs e.g. continue upper body, quads, glutes strength training if hamstring is strained
Mid stage
- Progress from isometrics to isotonic then isokinetic training when appropriate
- Rebuild range of motion
- Gradually rebuild strength: start with low intensity and higher reps, before progressing to increased intensity with decreased volume
Late stage (prepare for return to play or full training intensity)
- Focus on higher velocity contractions
- Work throughout the full range of motion
- Aim to return to maximal speed (mimic mechanism of injury)
Reducing Re-injury Risk
Rehab does not end when the injury is pain-free. Rehab should continue until the involved structures are more resilient than pre-injury levels. A strained muscle is most susceptible to re-injury in the first 4 to 6 weeks of return to play or training. Once the exit criteria for rehab is met, rehab should transition into strength and conditioning for ongoing maintenance. It is also important to identify and address modifiable risk factors to successfully rehabilitate and prevent future muscle strains. Common modifiable risk factors include: inadequate warm up, prior injury to the muscle or its associated joints, insufficient range of motion or flexibility.
Take Home Message
- Strains occur from loading a muscle beyond its capacity, causing excessive stretch
- Do not stretch during the acute phase of injury
- Rehab continues until the involved structures are more resilient than pre-injury levels
- Identify and address modifiable risk factors to reduce re-injury
References
Brukner, P. & Khan, K. (2012). Brukner & Khan’s Clinical Sports Medicine. 4th ed. Sydney: McGraw-Hill Australia. 20-21, 600-603.
Fernandes TL, Pedrinelli A, Hernandez AJ. MUSCLE INJURY – PHYSIOPATHOLOGY, DIAGNOSIS, TREATMENT AND CLINICAL PRESENTATION. Rev Bras Ortop. 2015 Dec 8;46(3):247-55. doi: 10.1016/S2255-4971(15)30190-7. PMID: 27047816; PMCID: PMC4799202.
McHugh, M. P., Cosgrave, N. H. (2010). To stretch or not to stretch: the role of stretching in injury prevention and performance. Scandinavian Journal of Medicine and Science in Sports. 20, 169–181 doi: 10.1111/j.1600-0838.2009.01058.x
Mueller-Wohlfahrt, H. et al. (2012). Terminology and classification of muscle injuries in sport: The Munich consensus statement. Br J Sports Med. p 1-10.
