Weekly musings, 4/1/18: Handedness, strength, and motor control

A 77 year old client came in recently, excited about a book she is reading on cognitive health. “I am using my left hand to do things around the house that I would normally do with my right. It’s supposed to be good for my memory.”

How we use our hands impacts strength and coordination. Which hand we prefer also influences how we use our brain,* so it’s not a stretch to assume learning how to use the hand that’s more awkward to do functional tasks might improve cognitive function.

Curiously, the hand that is more competent at specific tasks isn’t always the hand you write with; in one study, grip strength in 10.93% of right handers was found to be stronger in the left hand. In left handers, 36% had a stronger right hand than left, suggesting strength isn’t always correlated to hand preference. A number of factors could be at play, such  as injury and the fact the world is set up more for right handed individuals. As a left handed individual, I open jar lids with my right hand because it is easier to grip and twist to the right with the right hand as opposed to the left. Conversely, I would open a box with my left hand, since the task doesn’t require a specific direction. If I am seated next to a right handed person, I will often use the fork with my right hand so I don’t bump the person next to me, and I can cut with either hand.

Does my ability to perform tasks with both hands matter? Probably not, except that it allows me to feel fairly balanced in strength and coordination on both sides of my body. If a person so strongly favors one side of his body that he doesn’t feel secure supporting himself with the other hand or arm that will limit how he chooses to use his body during movement. An easy way to begin feeling more coordinated in the non-dominant hand is to consciously use it.

Try doing basic tasks with your non-preferred hand. Things like brushing your teeth, opening a water bottle, or opening a box are safe ways to see what it feels like to use your body in a different way. If you use ball exercises for hand eye coordination drills, use both hands to throw and catch. Do single arm strength work in the gym, observing how it feels to grip a weight and move it with your non-dominant hand, A little bit of awareness and conscious change can improve your sense of self and maybe even create a little more balanced strength.

*https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3153632/