In July 2021, physicians from the Institute of Sports Medicine in Copenhagen published an article about heavy resistance training and its role in improving symptoms and structural abnormalities after strain injuries. The article can be found in the American Journal of Sports Medicine.
The authors of the study found that heavy resistance training over 3 months improved pain and function, normalized muscle strength deficits, and increased muscle cross-sectional area in the previously injured region. Short-term strength training can optimize muscle function even many years after a strain injury, but it does not seem to influence the overall structural abnormalities of the area with scar tissue.
While the study was small (30 participants), it is encouraging to know there is research being done after a strain injury. However, the research is not without controversy. There are many physicians who may not agree with the study. Of course, it is always best to consult with a physician after any kind of injury. Physical therapy should be initiated under the direction of a physician after a strain injury.