To understand the title of this Physio Talks a bit better, it may help to know a bit about the neurological principle stated eloquently in the phrase, the brain knows movement, not muscles. Now, that is, like many succinct phrases, an over simplification. But, the essence is still true, the brain and spinal cord organize movements using many highly coordinated muscle contractions and relaxations to accomplish a movement task. The brain does not organize one muscle at a time, but many muscles whose interactions are marvellously timed to make a coordinated movement. When more strength is needed then more of some muscles become involved while others need to dampen their efforts, and others start to contract to make sure the joints involved are protected and move in the proper direction. It’s really rather marvellous to think about, actually.
So, when someone requires rehabilitation, or wants to get stronger at doing something or just more coordinated at doing something, the best way to go about it is to repeatedly perform the needed motions against resistance. The traditional way to go about retraining, or advanced training, and which is rapidly disappearing from PT as a treatment method, is to decide which muscle or muscles are the main ones responsible for the movement(s) under consideration and then developing an exercise program for each muscle to make it stronger, longer or whatever. So, if someone has difficulty rising from a chair because his/her thighs seem weak, the traditional exercise regime has the person sitting on the edge of a table and doing knee straightening exercise against resistance to make the quadriceps on the front of the thigh stronger, because they are the primary knee straighteners, and everyone knows that strength of knee straightening is very important to rising from a chair.
Will this exercise help the person rise from the chair more easily? Eventually, yes. But if the person needs to improve rising more quickly or if the person must not only rise but walk away as quickly as possible, then exercise specificity must be applied to the problem. So, rising from the chair is used as the exercise, which will not only involve knee muscles, but trunk, hip, and ankle muscles as well. To make it easier at the beginning of training, because the person wouldn’t be needing the physio if it was easy already, we might start from a higher seat. Then lower the seat to increase the effort as the person gains strength until we could have the person on a regulation chair height holding addition weight in their hands to increase the effort more, and they would then be strengthening everything needed to come to stand in a faster, easier and more coordinated fashion.
This example is just that, and example. But it works for many needed exercises. It even works with professional athletes, who are perfectly healthy but need to perform at a higher level in order to win over the competition. You will see pictures of athletes running with parachutes attached behind, or pushing against weighted sleds, or swinging leaded bats or throwing weighted balls, all using the required motions to accomplish the coordinated act while repeatedly doing the activity against higher than usual resistance. Exercise specificity.
So, the next time you find yourself needing to perform some activity better, either because of injury, disuse over time or wanting to compete at a higher level, consider the motion rather than the muscle.
These comments are general in nature. Be sure to check with your physio or doctor if you are not sure whether they apply to your situation.
Dave Rohe is a recently retired physio having practiced in New Zealand since 2004. He originally qualified in the USA, subsequently practicing in Malawi, Egypt and Cambodia prior to emigrating to New Zealand in 2003. He has enjoyed management positions in pediatric and adult outpatient facilities as well as taught physiotherapy for 15 years at the University of Georgia. He is currently living in Parakai with his wife, Sharon Robinson, a local midwife, near his adult children who are working, and one of whom is studying to qualify as a physio through the programme at the University of Otago. His articles previously appeared in local newspapers in Taranaki and on the blog site sponsored by NZSPT.