Do muscles have memory?
The term muscle memory is a little misleading. Muscle fibers themselves do not have or store memory. However, the functional component of muscle, the motor unit, consists of skeletal muscle fibers and their joining α-motor neurons. The motorneuron permits communication of electrochemical impulses from the spinal cord to the muscle. When neuromuscular pathways are trained through repetition, various locations in the brain (mainly the cerebellum) stores the information, and the muscle action becomes automatic. We have come to refer to this as “muscle memory” but really it is motor learning or learned reflexes and is a form of procedural memory.
The blogger Lifehacker mentions the phrase “practice makes perfect” defines our example of motor learning. It is true that hundreds to thousands of repetitions of a task such as typing, driving, or swinging a tennis racket, are required to “engrain” the movement pattern until it becomes an automatic action. Eventually these tasks do not require our conscious thought. Unfortunately, this also explains why hours of practicing the wrong or incorrect way results in learned bad habits or nonoptimal mechanics. Thus, it has been suggested the aforementioned adage should be modified to “perfect practice leads to more perfect performance.”
In sum: When muscles repeat the same movement over and over again the activity becomes habitual and does not require our conscious thought. Remarkably, by the well-designed programming of our neurological system, the action is learned, organized and stored on a non-conscious level making our actions automatic as though the muscles “memorized” the task.
Take home message: When learning a new task or learning an old task again for the first time after injury or rehabilitation practice correct mechanics several (*hundred*) times. Be patient with yourself. Your muscles themselves do not have memory. However, if you perform the task frequently and precisely the brain will engrain the movement until it becomes flawless and automatic in its execution.
Next pondering… Do reflexes work the same way? Stay tuned!
D. Krasnow, personal communication, June 24, 2012.
McArdle, W. D., Katch, F. I., & Katch, V. L. (2006). Essentials of exercise physiology. Baltimore, MD: Lippincott Williams & Wilkins.