There are good reasons for muscle strengthening after stroke, of course.
But therapists know these reasons well. For instance, the muscles on
the affected side, even the ones that are the most spastic and seem
overwhelmingly strong, are usually no more than half as strong as the
unaffected side. Because spasticity is such an issue after stroke, some
clinicians believe that strengthening "tight" spastic muscles will
exacerbate spasticity. Research has shown that this is untrue;
exercising muscles does not increase spasticity. It is important to
focus on the muscles that are the weakest, of course. For instance, most
stroke survivors have no problem at all bending their elbow, but
extending their elbow is often very difficult, especially at the end of
the range of motion. In this case it would be wise to work the triceps
because it is the weaker of the two muscle groups.
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So cardio and muscular strengthening are important, but viewed as more
of a "pre-process" than the process itself. In fact, many of the
leading-edge treatment options (i.e., repetitive practice, CIT, forced
use) are considered "intensive." They require that the survivor "hits
the ground running" and be able to withstand the rigors of the intensity
right from the get-go. In this regard there is a necessity for the
survivor to be in pretty good cardiovascular and muscular shape prior to
the initiation of treatment. Once the survivor has the stamina, the
focus comes off the body and shifts to the brain.