Exercise is Medicine

The best-selling medicines of the last decade were Lipitor (for high cholesterol), Plavix (a blood thinner) and Advair (for asthma)[1]. Look inside most American’s medicine cabinets and you’ll find even more familiar names such as Advil and Tylenol aimed at alleviating pain. One medicine you won’t find at the top of the best-seller list or in a medicine cabinet is exercise. But is exercise really medicine? And if so, what is its role? Most associate good health with frequent exercise—in the form of maintaining healthy blood pressure, lowering risk of obesity and a multitude of positive outcomes—but exercise is more than just a tool for prevention. The scientific literature tells us it may also be a tool to promote healing of musculoskeletal injuries.

THE KNEE BONE’S CONNECTED TO THE…

Modern medicine has developed very effective means for dealing with high blood pressure, indigestion, acne and all sorts of common bodily ailments. However, injuries to the musculoskeletal system have proven to be too complex for a single pill or cream to effectively treat.  What comprises this system? Not only muscles and bones, but also tendons, ligaments and cartilage. The role of each of these can be thought of as follows:

Bones: Support the body for movement and provide structure

Cartilage: Lie at the end of bones at joint surfaces and allow for smooth movement

Muscles: Move or stabilize bones

Tendons: Connect muscles to bone

Ligaments: Connect bones to bones

This multifaceted system of different tissues, in coordination with the nervous system, cardiovascular system—really every system in the body—is able to facilitate the activities we love to do.  Oftentimes, if there is something awry in this system, the end result is pain and limited movement.  Many medicines exist to alleviate pain and some of those common medicine cabinet options can do the trick. However, alleviating pain in the short term is different from identifying the cause of injury, repairing damaged tissue and developing strategies for prevention.

TROUBLESHOOTING THE MUSCULOSKELETAL SYSTEM

Pain is an experience that is unique to each individual and influenced by many factors including our beliefs about pain, previous experiences, stress, amount of family support, amount of structural damage, sleep and even our expectations of recovery. Although pain can be helpful to alert us when something is wrong—think a siren shouting, “WARNING, WARNING”—it doesn’t provide much information about the what, how and why.

While pain relievers are effective at managing the pain signal, the medications won’t necessarily promote the healing process.  Consider the example of a cyclist who rides consistently about 5 miles or so each time he goes out. However, one day he decides to ride 50 miles at a fairly fast clip. During that ride, he strains the quadriceps in his thigh. Even after he finishes, pain in the area persists for days. But what exactly happened? With every tissue injury, the body undergoes a 3 step process for tissue healing:

1) Inflammation: At the time of the injury and during the first week, higher pain levels, redness, swelling and tenderness are all signs of inflammation. During this stage, pain relievers can be effective pain management tools and activity should be limited.

2) Proliferation: As pain levels subside (because of decreasing inflammation) the body begins to replace damaged tissue with collagen protein (the building blocks of tissue).

3) Remodeling: The body utilizes the raw material of the proliferation stage to restore the damaged tissue to normal functionality—albeit not identical to what it was before.

Pain relievers and traditional medicines may not adequately promote tissue healing in the proliferation and remodeling stages. While resting is an option—and a good one during the inflammation stage—this approach will not be highly effective at stimulating healing either.

Key takeaway: Pain relievers and rest help manage pain but may not effectively promote healing and repair

Moving is healing

Across a wide range of musculoskeletal problems, physical activity promotes our body’s inherent ability to heal itself.  Musculoskeletal healing is aided by a process called mechanotransduction, which is the conversion of an external stimuli (e.g. exercise) into an internal signal which promotes tissue repair[2].

The process of mechanotransduction can be thought of in three general steps which our bodies (at the cellular level) go through:

1) The Stimulus: External stimulus is applied to the body in the form of exercise. How much exercise? Ongoing research is being done to determine what’s optimal, but targeted movement is key.

2) Cell-to-cell Communication: The external stimulus activates the cells affected by the movement to send signals to all neighboring cells in the tissue. 

3) Effector Response: The signals stimulate the production of the building blocks of the tissue (i.e. protein) within each cell for tissue repair. 

What’s the bottom line of this process? During the proliferation and remodeling stages, chemical signals are needed to stimulate the creation of raw materials to repair the damaged tissue. Exercise does just that by encouraging this process at the cellular level.

All medicines have their place and role in healing the large variety of ailments we face and it’s important to consult your physical therapist when feeling pain or discomfort. In this brief overview, we have described how exercise—in addition to its other preventative benefits—can also be thought of as another tool for actively healing musculoskeletal tissue.

Why does it matter?

We have many tools to manage pain and inflammation. But that’s not the full story. Our bodies need to also rebuild and repair what’s damaged to restore functionality. Exercise effectively encourages that process when done correctly and Physical Therapists are trained experts in prescribing exercises which facilitate our own body’s incredible potential for healing and building resilience.

To learn more about how physical therapy can help you, visit Move Forward!   

References

1. http://www.genengnews.com/the-lists/top-10-best-selling-drugs-of-the-21st-century/77899716
2. Khan KM, Scott A. Mechanotherapy: how physical therapists’ prescription of exercise promotes tissue repair. Br J Sports Med. 2009;43:247–251. doi:10.1136/bjsm.2008.054239