Muscle memory is a function of each muscle in our body.  Each cell in our muscles remembers position and tension. These muscles allow us to make complex motions like walking without having to think about each muscle's movement.  Could you imagine if you had to think about every muscle’s action with every step?  We would never survive.

This critical function also makes a great challenge to fixing errors in our motion. Do you make the same error all the time?  Or the same mistake in a piece of music on your favorite instrument?  These are examples of bad muscle memory.  Swimmers, like in any other sport, can develop muscle memory errors.  Here is some critical advice for correcting muscle memory errors:

• Muscle memory is like a tire rut in a dirt road. If you get too close to the rut the car keeps falling into the existing ruts. To get away from the rut, it can be best to overcorrect.  Then when you are no longer near the rut you can make small, incremental changes without being so close to the rut that you fall back in to your old mistaken habit
• Small changes feel large. Don’t let your body fool you. A shift in angle of 5 degrees can feel, to the swimmer, like they are shifting 30 degrees or more. 
• Consistent attention to the change is needed to successfully change.  You need to think about a change every day, every length, and for some changes, even every stroke for about two to three weeks to successfully overwrite the existing incorrect muscle memory.  The good news is, once you have ingrained the new movement it will be the new “rut” and require very little thought to do correctly.