Our bodies have the ability to re-build after injuries and the key to unleashing this ability is exercise. I was recently talking to a student of mine and realized that the foundation of everything that I was teaching him went back to the question of, WHY?! For example; “yes, we know exercise works, but why?” This made me think that this information would be valuable for patients.
The most important thing that you need to take from this is the concept of BIOPLASTICITY. This idea sits at the core of everything a physical therapist does. Generally speaking, the term means that our tissues (aka our biology) have the capacity for change (for the good or bad) with stress (either applied or removed). Through this mechanism we can do one of three things: 1) get in better shape, 2) get out of shape, or 3) get injured. Here is how:
Let’s start with an example we can all relate to: the skin on your hands. Here is a hypothetical: you work a desk job and don’t do much heavy lifting in your regular daily life. If this is the case, then it is likely that the skin on the palms of you hand would likely be very soft and smooth. This supple skin is your body adapting to your daily life of performing light and dexterous tasks. Now, spring comes and you get a load of mulch for your yard. You have two options here: 1) spread a bit each day for the next week or two, or 2) spread it all on Saturday, no matter what. If you go with option one, over the course of the week, you will start to notice callous formation on the palms of your hands. This skin will become rough and more thick. This is an adaption to your new activity to allow you to withstand the new stress of shoveling. We will touch on option two later.
This same adaption happens in every tissue of your body. In your connective tissues (muscles, tendons, ligaments, skin, bone) it is called Machanocoupling (British Journal of Sports Medicine Article). Specific to bone, this is called Wolf’s Law, which means that the more load makes a bone stronger. This is an incredible tool! This means that if we have an injury in the muscle then the solution is NOT rest, it is action. (An important note is that relative rest during the initial few days of inflammation is indicated, but limited to only a few (1-5) days.) Once we are out of the inflammatory period we will start to progressively load the injured tissue and continue to load it in a number of different ways until it is ready to return to whatever activity injured it.
Before those with osteoporosis jump up and go for a run, let’s talk about option two from above. This process MUST be slow and progressive loading. I am taking big risk telling people this, but I would not have a job if everyone abided by the idea that too much load too fast leads to tissue break-down and injury. So, if you shoveled all 10 yards of mulch in one day then instead of a nice strong callous you would have some painful, nasty blisters (aka tissue breakdown). The same thing happens to all of your connective tissues. So take your time and build slow.
We can apply some similar ‘stress’ principles to the brain. In the brain this is called neuroplasticity, and this idea is most evident with stroke patients. When a patient has a stroke and has a loss of control over an extremity, the best way to improve their control over it is to force them to use it. Here we are relying on the body’s ability to develop new pathways through the brain. This applies to the healthy brain and our ability to learn new tasks. We move through our life by setting off neurologic patterns of movement that run like a program through our brain. As I sit here and type this, I am not thinking about every single letter that I type, my brain is operating on a program of movement that I have developed over the last number of years. If (for some terrible reason) someone completely re-organized my keyboard, then It would take me about three weeks of work to write a new program. This is because it takes about three weeks for the brain to re-write itself. It would take longer to perfect the program, but that is the difference between competence and excellence. Where competence can take three weeks, excellence takes 10,000 hours.
These progressive training ideas also apply to the vestibular system (inner ear, responsible for balance). This system helps our brain understand where our head is in space and there are times when it can start to function at a lower level than ideal. This is called vestibular Hypofunction. This occurs as a result of injury to the system (ie. head injury) but can also happen as a (somewhat) normal result of aging. Regardless of the cause of the hypofunction we can work to improve the function by stressing the system. This process is called Habituation. In physical therapy we can do exercises that force the vestibular system to work which results in adaptations in the system that improves the function of it over time.
The idea of bioplasticity is a powerful tool and it is at the core of all of what we do in physical therapy, exercise, learning and life. We need to make sure we are STRESSING our bodies the enough to stimulate improvement and not too much to cause injury. To strike this balance consultation with a professional is often needed. This is where we your local physical therapist comes into play, so give him/her a call!