I've been walking improperly all my life

This line of thought began when I noticed I could enter the length of my stride on the computer for greater accuracy in the recording of miles per day on my Fitbit.  If you don't enter your stride length, they just use the average length stride for a person of your sex and height.  So I went to a recently-tilled area of the garden and walked several paces.  When I measured my stride, it was thirteen inches.  My big old feet are almost a foot long, which means I am taking tiny steps.  Cliff was sure I had measured wrong, but I had not.
When I put my puny stride-length on the computer, my miles walked per day dropped drastically.  The number of steps, of course, remained the same.  I removed the stride length from the computer, because I would rather live under the illusion that I walk six miles a day rather than four.  
As we were going for our morning walk a couple of days ago, I remembered something:  one thing my home therapist kept harping on when I was first recovering from knee replacement was the way I walked.  She insisted that my heel should touch the floor first, then the rest of my foot.  That is unnatural to me.  I walk flat-footed, the entire sole of my foot touching at the same time.  Once I was done with that silly therapist I went back to walking the way I always have, with sort of a shuffle.  
So there we were in the pasture, and I began watching Cliff as he walked.  Wonder of wonders, his foot touched the ground heel first!  Back at the house I did some Googling and found that I am indeed an odd bird, because humans are supposed to naturally walk heel-to-toe!  
Next day as we walked, I concentrated on walking properly and found my stride increased greatly, without my even trying.  When I can remember to do it, I try to walk that way all the time, but of course sixty-nine years of walking improperly are difficult to overcome.  Wait, make that sixty-eight.  I don't think I was born able to walk, although my mother did think I was a precocious child.  
Maybe it's coincidence, but my knees don't seem so achy when I've walked properly a good portion of the time.  
I can't imagine why I walk improperly.  Perhaps it has to do with the fact that I've spent most of my life barefoot.  Just another thing that makes me special, I suppose.