How Exercise Helps with Tissue Healing

Exercise therapy seems to be a panacea for just about all human aliments (depression, anxiety, low back pain, neck pain, osteoarthritis, etc…). Sometimes it isn’t clear how exercise can help with tissue healing such as tendinopathies and cartilage issues. This post will discuss how exercise can help with musculoskeletal tissue healing. 

One of the purposes of using therapeutic exercise is to create a desired response in the tissues. The use of exercise for treating bones provides a glimpse into the use of exercise to improve healing. For example, a mechanical stimulus to the bone will stimulate osteoblasts which will increase the strength of the bone, thus aiding in recovery. The mechanism used for bones, can also be applied to various soft tissues such as muscles, tendons, ligaments, and cartilage. 

The mechanism of how exercise helps with tissue healing is called mechanotherapy. Mechanotherapy is generally broken up into three stages (1) mechanocoupling, (2) cell-cell communication, and (3) an effector response. 

Mechanocoupling refers to the conversion of a mechanical stimulus into a chemical response. The mechanical stimulus (exercise) deforms the cell which causes the cell to react by producing various chemicals. The duration, frequency, and intensity of the mechanical stimulus can produce various chemical reactions. This is part of the reason why loading of tissues is vital for recovery: too little load and no response is created while too much load can lead to an adverse cell reaction. 

The next stage is cell-to-cell communication. While each cell may not be subject to the mechanical stimulus, cell-to-cell communication allows the cell of the body to act as a unit. The chemical message created during the mechanocoupling stage is distributed to other cells in the body. This stage is of particular importance to post-surgical rehab and when rehab is too painful to complete. By doing rehab in other areas, cells in the targeted areas can indirectly benefit from rehab (for example, exercising the opposite leg while recovering from an ankle or knee surgery). 

Finally is the effector response of the cells. When dealing with damaged tissue, this usually refers to stimulation of the processes responsible for creating new tissue. With the creation of new tissue, this will also stimulate reorganization of tissues in response to the stress in the tissues. This helps the tissue to become stronger in the correct orientation to the forces that will be placed upon it. 

As touched on above, appropriate loading is vital for recovery. Trying to max a deadlift after a disc injury may not be appropriate for tissue healing, since tissue capacity may be compromised. Matching an appropriate exercise for a given tissue capacity will ensure that exercise is beneficial. 

Whether you are in pain or are fearful of re-injury, starting to exercise following an injury can be a scary experience. It is important to note that pain is not indicative of tissue damage. Think of pain as an alarm system, alerting you to a threat to your body (just because the motion light outside goes off doesn’t mean someone is breaking in… it could just be the postman delivering a package). A thorough examination by a profession can determine if there is tissue damage that would make exercise contraindicated. Assuming that you have the green light from a professional, exercise can be of great benefit for recovery.

References:

Khan KM, Scott A. Mechanotherapy: how physical therapists’ prescription of exercise promotes tissue repair. Br J Sports Med 2009; 43:247-252.