When I do my neurokinetic therapy muscle testing, I am not looking for strength. I am testing whether or not the brain recognizes muscle function. When strengthening muscles, other muscles will kick in and compensate. Body movement is not a one muscle job. Our body's wonderful ability to compensate, is how we are still able to go about our daily activities after minor injuries. Compensation has its place and is not a dirty word. Even when compensation causes pain, it is your body's way of letting you know that something needs attention. When we ignore those signals, that voice will get louder.
When I do neurokinetic therapy, the goal isn't to prevent your body from never compensating ever again. That is impossible. The goal is to correct movement dysfunction, so that the compensations that do happen, will help you move better and feel better. Certain compensation patterns do need to be avoided as much as possible, in order to continue moving and feeling better, since you will want the results to stick.
You can have a muscle that is strong and still not function properly. An example would be everyone's favorite area of the body, the core. Many fitness people have a strong enough core, but when I do the neurokinetic therapy muscle testing, the fitness people's cores generally test the most dysfunctional. That is because when we workout, the tendency is to push through the exercises after reaching the point of fatigue. THAT is when compensation can happen. Also, clenching other areas of the body can create compensation, as well. The jaw compensating for the abdominals is a very common connection. Also, the diaphragm, as we sometimes hold our breath, when pushing through something. That is also why many people will do certain exercises that make are supposed to make them feel better and they sometimes end up feeling worse, instead. Strengthening or directly massaging a muscle that is dysfunctional, can create more compensation patterns, resulting in more pain and dysfunction. Being properly assessed can get your muscles functioning properly again. You may also need to modify your workout in order to keep them properly functioning.
I am a massage therapist, so this is not advice about strength training. This is to explain the difference between muscle strength and muscle function and know that they are NOT the same thing.