How Physical Activity and Sleep Affects My Writing

Over the last 5 days or so, my writing has been going pretty well. Writers have different explanations for this phenomenon. My “muse” is alive. I’m firing on all cylinders. I’m in the zone. But these are all vague, unscientific explanations for an explosion of creative brain activity. It can be helpful to isolate patterns to see if anything external to writing itself could affect writing output or how writing “feels.” Since I capture a ton of data about my writing, my physical activity, and my sleep, I thought I’d look into this.

Does physical activity affect my writing?

Over the last week and a half or so, my walking has been up. I’ve averaged about 17,000 steps per day, well above my daily goal of 15,000 steps. These walks invigorate and energize me, and I couldn’t help but notice that when my walking was up, my writing is also up, and seems to go much more smoothly.

So I culled the last 300 days worth of data for writing and walking and looked to see if there was any correlation between them. At first glance, there doesn’t seem to be.

Figure 1 above plots the number of steps I take each day against the number of words I wrote on that day and creates a linear model fit to see if there is a correlation. Each point on the plot represents one day. The x-axis is the number words written. The y-axis is the number of steps taken. The line represents the linear model. It is almost flat, meaning there is no real correlation between these value. The slope of the line itself is slightly positive, and given its value, this would be considered a “weak positive” correlation, but when I say “weak” I mean really weak.

You can see some interesting features. On days where I write a lot, there appears to be a tendency for me to walk a lot, too. But again, it is a weak correlation.

Next, I decided to look at days where I exceed both my writing goal (500 words/day) and my walking goal (15,000 steps/day). That resulting in the following:

In Figure 2 there is a slightly negative correlation between writing and walking on days where I exceed goals for both. In other words, on these days, the more I walk, the less I write. I suppose this makes sense. I might be more physically tired. If walking takes up more time, there might be less time for writing.

Finally, I looked at days on which I was below my goal for both writing and walking.

In Figure 3 you can see this data has a much stronger positive correlation, although based on the actual slope it is just barely into the territory of a “moderate” positive correlation. On these days, the more I walk, the more I write.

How does sleep affect my writing?

I’ve been sleeping pretty well over the last 10 days and so it is naturally to look at that data as well. Here, what I did, was looked at my total minutes asleep, and how much I wrote the following day. Here is what the data looks like for the same 300 day period.

In Figure 4 you can see a weak positive correlation between the number of words written and the number of minutes I slept the night before. The more I slept, the more I wrote. During that time I averaged 435 minutes of sleep each night (7 hours, 15 minutes) and write 840 words/day. The weak tendency in this model is that if I slept longer (say, 8 hours) I would write more, in this case, the model predicts 863 words, only about 23 words more for 45 additional minutes of sleep. Like I said, it is a weak correlation.

---

In this case, the data doesn’t point to any one thing that I could change in order to get more of the really good flowing days of writing stacked up one after the other. Sleep helps a little. Walking helps a little. But in neither case do they make a significant difference. At least for me.