***To actually PRACTICE mirror movement development (MMD) while reading this article, read it ‘backwards’ using the MirrorRead.com web browser extension***
What is MMD?
The human body, with its symmetric skeleton, symmetric exterior sensory features, and symmetrically-weighed distribution of asymmetrically jumbled internal organs, is made for mirror movement development (MMD).
The same goes for a car: symmetric frame, symmetric exterior features, and a symmetrically weighed sum of asymmetrically placed internal components. You would never, though, buy a car that only makes right-hand turns. So, why do we settle for human bodies that only make “right-hand turns” when it comes to handedness?

There is no biomechanical reason for unilateral development (exclusive right- or left-handness) since nothing in the design of nature demands favored development of one side over the other. Rather, we as humans choose to shortcut our development through designing culture in such a way that favors preferred development of just one side; in this case, the right side over the left.
Balancing this out means working to develop dominance on both sides (called dual-dominance). Achieving dual-dominance comes down to just one thing: practicing MMD.
And how do you practice MMD? It’s simply a focus on mirror developing your non-dominant side in all activities, using your dominant side as the teacher.
Difference between MMD and Ambidexterity
The ability to use both hands has been referred to as ambidexterity. The first known use of this word dates back to the 1530’s. ‘Ambidexterity’ literally means, “right-handed on both sides.”Since human hands are mechanically designed for equal performance, ambidexterity is a less-than-accurate term; comparable to still calling Native Americans ‘Indians’ after learning they’re actually not from India. The goal of MMD is not to become “double right-handed,” but to connect to your true, bilateral design for symmetric movement and engage both sides equally.

Ambidexterity has often been discussed as something that someone is simply born with. On the other hand (quite literally the other hand), MMD is a lifestyle choice that has been practiced throughout history. It requires daily practice that grows and advances over time, for anyone at any age. Because ambidexterity is still a more culturally understood concept though, I refer to MMD, at times, as ambidexterity.
While ambidexterity is doing everyday activities with either hand in the traditional direction (e.g. writing English with either hand in the left-to-right direction), MMD is similar, but with the major difference of incorporating mirrored direction. This mirrored direction provides equal micro-muscular development to both sides, something traditional ambidexterity falls short of.
The MMD difference can be best seen with reading and writing script. For example, when writing in the traditional direction with the right hand, you exercise more pulling muscles. On the contrary, writing in the traditional direction with the left hand, you’re exercising more pushing muscles. When you engage in MMD writing, though, you’re mirroring the muscle groups identically, thus using equal pulling muscles from both sides of the body. If you grew up as a traditional ‘lefty’, this concept is the same, but reversed, so you are pushing in both, respective directions when MMD writing.

Of course, mirrored script is most easily read when using a mirror. If you want to experience brain growth, though, you need to work at learning to read mirrored script without the mirror. And by the way, all of Leonardo da Vinci’s personal notebooks were written in mirrored direction, even often inverted.
Another example to understand MMD can be seen in playing mirrored kickball; players kick and throw the ball from their non-dominant side and round the bases in mirrored direction (running to the left instead of to the right, the traditional third base becoming first base).
Understand it yet? As you can imagine, MMD is even more of a brain and body workout than practicing traditional ambidexterity alone.
Important to note is that ambidexterity and dual-dominance exist on a spectrum. Proficiency depends on how much you practice development of your less-dominant side.
Thanks to the accounts of other contemporary MMD practitioners, I’m convinced dual-dominance has little to do with genetics or how you were born and everything to do with practice, practice, and more practice… aka, MMD is a lifestyle choice.
While you may never achieve a perfectly equal development of both sides, you can get closer and closer everyday. And with every day of practice, your body will feel better and better, mentally and physically capable of more and more.