Over the years I’ve had a number of overuse injuries: tendinitis from too much typing or mousing or music playing, a sore shoulder from too much swimming, painful knees and ankles from too much running. The key phrase here is “too much” and you’d think I’d learn my lesson eventually. But no. When I get excited about doing things I overdo and then, periodically, must back off and recover.

Often, during recovery, as I analyze what’s gone wrong, I find that the problem is not simply overuse but more specifically asymmetric use. Once, during a bout of pain in my right thumb joint, while pondering what the cause might be, I looked down at my hands while I was typing. Clatter clatter clatter BAM! Clatter clatter clatter BAM! The BAM was my right thumb pounding the space bar. I could feel a twinge every time I saw it happen.

In some cases, and that was one of them, shifting to a symmetrical pattern of use is helpful. (As is, of course, not pounding.) I’ve trained myself to alternate thumbs while typing (although, as I look down at my hands now I see that needs reinforcement), to breathe alternately left and right while swimming, to change mouse hands from time to time, to become a switch hitter with the garden shovel.

Every time I go through one of these retraining exercises I reflect on the difficulty of the process. The steps are:

- surface a bad habit that was unconscious

- consciously develop a good habit

- submerge the new habit back into the unconscious

In the latest iteration of the process I am relearning how to walk. It sounds ridiculous. It is ridiculous. But here’s what happened — or rather, my best current understanding of what happened. About a year ago I strained one of the adductors in my right groin. Usually things like that resolve with a bit of rest and some stretching. But this time it didn’t. Last summer I was having trouble lifting my right leg over the bicycle seat when mounting. When the same thing happened on the first ride of this season I knew something had to be corrected. But what?

An acquaintance who does massage asked me to observe the angles of my upper legs while cycling. Next time out I looked down and could hardly believe it. My right knee was out of line by at least 25 degrees! That misalignment was clearly aggravating the injury and not allowing it to heal.

When I got home I put cycling and running on hold and went back to basics. I stood in what felt like a normal position and looked down. Sure enough, my right foot was pointing out noticeably. When I aligned it with my left foot I felt like I was forcing it to pigeon-toe. Then I started to walk. Each step required a conscious effort to align the right foot. It didn’t feel correct. But I could see that it was.

So that’s how it’s gone for the past 5 days. Instead of cycling or running I take the dogs for a hike and focus on alignment. I have to supervise my right foot closely and, when I go up and down over obstacles, I have to supervise my right knee to make sure it stays aligned too.

I can tell that it’s working. But clearly a bad habit that took a year to develop will take more than a few days to correct.

Every time something like this happens I wonder how I could fail to notice something so fundamental. But it really isn’t surprising. We can’t consciously monitor how we use our bodies all the time, and bad habits develop gradually. If there’s any application of wearable computing that will matter to me I think it will be the one that warns me when these kinds of bad habits begin to develop, and helps me correct them. We’re not great analysts of the forces in play as we use our bodies, but computers could be.