Thanks all for posting. As I've kept up with competitive play since posting, I have thought about this thread a lot, since then, as I've continued to wonder about what affects the chess-playing experience I've had since then.
I had a flash of insight while I was home for the holidays about all this:
So at first, I was thinking about how on earth you would test anything out. Because I think there is a short-term factor, mental performance, crossed with a long-term factor, which is learning about and understanding the deep models of chess. So at first I was a little stumped: how would I test mental performance across tournaments, when tournaments are spaced out by months at a time and there's going to be some learning happening (I hope!) along the way?
But then! I realized that in the Bay Area, there are 2 evening tournaments, that both happen at night, and have the same time control (i.e. length of game), and that I could pick a performance mod for 1 tournament and not do it for the other, and I'd have some kind of A/B test where I'd control for my deep / long-term learning.
So, that's cool! Though knowing myself, I often become uninterested in experiments when the difference is obvious (since part of this is my own subjective experience of how lucid / tired I am at the board) -- but I feel like teasing out what affects mental performance has been too subtle to be as simple as 'just exercise beforehand' that experimenting could be worth it.
Another way of saying that is -- if I just felt more lucid at the board, ultimately I want to think more clearly and play better, and I'd just want to start doing that all the time. I guess one question is -- what things are actually impactful? I feel like parameters include nutrition, exercise, time spent meditating, sleep, and then maybe study specific to the upcoming game (since in both of these tournaments you can look up your opponent and their past games prior to the game.)
Some idle observations I've had:
One day, in the fall, I had a bodywork session (Feldenkrais work), and then went to play one of the most lucid chess games I've ever played. I felt like I had the lucidity of my mind at say 12 years of age -- just astounded at how clear my mind felt and the quality of moves coming out of my hands. The result of the game is interesting -- I was playing a player considerably stronger than me (by rating he had an 85% chance to win and I had 15%), but by the time we got to the first time control (30 moves, around 2.5 hours in) I had an easily winning game. Well, not easily enough, because I think just straight fatigue overcame me and I proceeded to give the game away in the last hour / hour and a half. So I lost the game, but I could palpably tell that I was playing far stronger than I normally did, and it felt very connected to the sense of clarity I often have post bodywork.
More recently, I have been playing with the Slow Carb Diet, Tim Ferriss' invention from the 4-Hour Body. It has a noticable impact on bodyfat and lean muscle and all that, but playing chess has had me wonder if there are hidden drawbacks. I felt very, very sluggish at the chess board the last two weeks I was on the diet. I've switched to an earlier morning work schedule lately, and perhaps that is why I felt so exhausted. I could look it up, but I've been on that schedule for more than a month now -- so I don't think that was it by itself. It was astounding to me that I felt extremely slow at the board both times, and sometimes I will get a second mental wind while playing, but both of these games I just felt like there was cotton in my mind. Things were confusing and fuzzy.
This made me wonder a lot about how I was practicing the slow-carb diet, and if there was some fuel the brain was used to having which in the name of lower bodyfat and conventional attractiveness I had thrown out the window.
Or maybe I just needed to tweak my diet on those days. I remember playing 10 years again, when I was 20, and chugging peanut butter banana milkshakes during all day tournaments, without any notion of "optimal diet" to chain me.
So anyhow, those are my thoughts. The realization that there is a way to test for performance across two tournaments is an interesting one to me (though to some extent, performance feels self-evident in how sluggish / lucid I feel in the moment -- so I don't know if all the work of spending 2 nights a week playing chess for some weeks is needed.)
The ideas around blood sugar really interested me, after the slow carb experiment I did, and an EEG would be awesome (because I really feel like lucidity at the board is a huge part of what makes playing both enjoyable as well as successful -- so getting more information there could be great. Related to that -- I find it's not terribly fun for me to play when I feel really tired or exhausted. I find I don't mind losing a game where I thought clearly, but I do mind losing games where I feel like I'm just not thinking clearly.)
I think know what I am wondering is what is an actionable experiment -- what device would I get or measure would I use, and then what would be the experimental behavior that I play with? Design wise I would love for this to fit semi-naturally into my life (like 2 nights of chess a week is both incredibly tempting and a bit of a stretch time-wise ... but I think if the experiment felt worth it, I am so curious about how all this works that I'd just go do it for a bit.)
Any thoughts -- or any ideas as to who might find this idea interesting -- would be very welcomed.