It's All in My Mind

Healing injuries with progressive overload in physical therapy.

Progressive overload is central to the thinking of physical therapy. You can conceptualize many injuries as manifesting a loss of performance. If you want to get your body back to “normal,” that’s just improving performance from a deficit. Can this deficit be bridged by inducing adaptation through progressive overloading? If you believe that going to the gym makes you more fit, it should be unambiguous that physical therapy should work with the same principles.

But I’ve talked to lots of people who were skeptical. This connects back to the causal riddle of why we believe in some counterfactuals and not others. People believe that going to the gym makes you stronger. Why is it harder to believe that PT can help heal you faster? I’ll provide a partial answer, but I know I have some doubtful readers out there, and I’d love their own thoughts on their PT skepticism.

I think part of the issue with PT is that we don’t immediately think of healing as an adaptation process. We expect our bodies to just do it. Part of our experience as children reinforces the idea that we’ll just heal after a little niggle. And we also know that picking at a scab makes it worse. If you google how to fix a muscular injury, the first thing that will pop up is “RICE” (Rest, Ice Compression, Elevation). So maybe physical therapy is working in the wrong direction and worsening the damage. Our body should work on its own to get back to normal if we just rest, and maybe these exercises in PT are just a distraction.

But so many of the processes required for healing an injury (like recruiting neurons and growing muscles) are those we’re inducing with exercise. Why shouldn’t you be able to heal something by progressively loading it?

Part of the other issue with physical therapy is that “newbie gains” are often much harder to come by. Physical therapy can take an excruciatingly long time to work. Let me draw on another personal experience, and it’s one where I can’t imagine any other counterfactual explanation.

One of the reasons I was looking for a gym in 2019 is that I had developed a neuroma in my right foot that made running impossible. The neuroma made it feel like I always had a pebble in my shoe. I tried to fix this with orthotic shoes and inserts, but nothing worked.

My coach, Patrick–now a recurring character this week–suggested that many of my issues had come from “weak feet.” Who even thinks that their feet have muscles in them? Which machine at the gym do you jump on to strengthen your feet? I learned some exercises later in working with a physical therapist. I was prescribed “controlled articular rotations” (CARs) for my toes. Here is what this is supposed to look like.

You should try these. They are not easy! It is completely unnatural to articulate your toes like fingers. I found it frustratingly impossible. I would stare at my big toe for minutes and nothing would happen. I would tell it “move” in my mind. Still nothing. It made me feel like I was a crazy person practicing telekinesis. But after a couple of months, my big toe moved. And then the rest followed. And now I can do all of the exercises. Somehow, my nervous system convinced itself to wire those connections together. I feel weird even typing this out! But the crazier part is I’ve been able to do this with other muscles.

This discontinuous jump from nothing to something is compelling evidence that the intervention “worked.” Perhaps I’m deluding myself with hippie, new age, Berkeley bullshit. But it’s another example of a set of principles that seem to convince bodies to do things they don’t know how to do. I’ll give another, definitely more controversial example tomorrow.