For an explanation of my rating system, and why it is skewed high, please see this prior post. Based on 43 weeks' worth of daily data, going back to September, here are my average percentages by day of the week:
First, it should be noted that there isn't a huge variation in the averages. My worst day of the week, Monday, is only about 3.5 percentage points lower than my best day, Sunday. I rate myself in increments of 5%, so this is less than one full increment. A statistician might tell you that these differences are not "statistically significant."
But if I'm to draw a conclusion from this, I note there is a gradual rising pattern from Monday through Friday. My best days are typically Friday and Sunday, with Saturday not too far behind. There are a few possible explanations for this.
I suspect that if you asked anyone who works a regular 9-5 job to track their daily mood, the pattern would be similar to what you see above. Weekends would be the highest, and Mondays would be the lowest. Although I've tried earnestly not to let mood affect my daily health rating, it's possible that I've let a little mood bias seep in.
Post Exertional Malaise (PEM) Effects
In terms of pure physical exertion, I expend more energy on weekends. As hard as I might try to relax, I can't seem to help it. Just walking from one room to another, and up and down the stairs in my house is more exertion than sitting in my desk chair at work. (Stress and mental energy, on the other hand, are higher on work days.)
Given that many PWME's cite a lag time of 24-48 hours between exertion and malaise, my weekly pattern might show that I crash from the weekend on Mondays and slowly heal throughout the week.
If, on the other hand, work was causing me to get worse, I would expect my weekday pattern to reflect a gradual descending pattern, where, as the week wears on, I slowly fade into poorer health. Instead I see the opposite - I get better as the week goes on.
I realize this theory runs counter to the prevailing thought in ME/CFS circles about the effect of work, but I'm just noting that, in my particular situation, it's one possible interpretation of the data. I'm not trying to say that work might be making me better, but rather, that it's possible I need to get better at relaxing and healing on the weekends.
If on the other hand, stress is negatively affecting my ME/CFS, my lower weekday ratings might be a reflection of increased cortisol (a stress hormone) on work days. I don't normally think of my job as stressful per se, but every job comes with some stress I suppose. This interpretation assumes a more real-time cause & effect relationship, with no lag. But why would my health follow a gradual upward trend throughout the week? My stress, what little of it there is, remains pretty much constant throughout the week.
If I had to guess which one of these interpretations is correct, I'd guess mood bias. I also want to note that processing the data in this way says nothing about the long term effect of working on ME/CFS recovery. It could be that working or not working has an effect on one's recovery which can't be measured by small weekly fluctuations.
Sorry to draw you along this far only to tell you...I don't know. Still searching for an answer on this issue.