Discipline Fatigue

I was brushing my teeth this morning while doing hamstring stretches with one of my feet propped up on the bathroom counter. 

I do this every time I brush my teeth. I do this because it’s part of my physical therapy back pain prevention routine. I do it to offset the impact of sitting at a computer for part of my day.

Ideally, I should be doing 60 minutes of physical therapy every day. I have an old rotator cuff injury, an old hip injury that I need to prevent from recurring, and the list goes on and on.

I don’t do what I intellectually know I should. It’s not because I don’t have the time or energy. For me, it’s just mental discipline fatigue.

This is why I do part of my physical therapy while brushing my teeth. I’ve been brushing my teeth since I was a child. It’s automatic; I never think about it.

When I do something extra while I brush my teeth, it takes no extra discipline, and I can’t really do much else during those two to three minutes anyway.

What I’ve come to appreciate is that different kinds of activities have varying “discipline” levels required to get them done.

Some things that I don’t really enjoy doing (e.g., preparing tax returns) require a lot of discipline energy “units.” I call these DEUs.

It’s useful to think about the number of DEUs required for various activities in your life and how you can get the highest return per DEU.

A few things I’ve found helpful:

Tim Ferriss, the author of The 4-Hour Work Week, first introduced me to the idea of batching similar activities together. For example, I try to group all of my phone calls into a single time block. The amount of energy needed to schedule two necessary, but not particularly enjoyable, phone calls is more like the DEUs needed for just one call (instead of two).

One of my readers passed along a suggestion from James Clear, author of Atomic Habits. Apparently, Clear suggested attaching a new desired habit (which, in my mind, requires a lot of DEUs) to an existing “automatic” habit (that, in my mind, doesn’t require any DEUs).

I realized that this is why I find it easier to do my hamstring stretches while brushing my teeth.

The value of qualitatively measuring DEUs is that you work on optimizing the return on your investment.

There are some kinds of activities that I really enjoy and require no DEUs. Others are excruciatingly painful.

It’s useful to think about whether your work is something that requires a lot of DEUs or very few. What about your various personal relationships?

Which things do you have to “force” yourself to do? Which are relatively effortless?

This is important to think about because you have a limit. We all do. We only have so many DEUs available to us before we burn out.