I did tests for weight loss. I found that you don't lose weight until you sleep. (stay up all night and weigh your self repeatedly, in the morning, no loss, but after you sleep and wake, your weight goes back to "morning weight") I found that if you don't sleep well, you don't lose as much. If you eat too late before going to bed, you don't lose as much. If you adjust your diet (however you want is my experience) to…
I sweat like a pig anytime I work out. I use to teach two hour fitness classes and even now after the end of a workout, I’ve “lost 5 pounds” but that’s pure water weight. I’m burning around 1000-1200 calories during that time. If I rehydrate and drink lots of water afterwards, I’ll “gain” 3 pounds.
If you are “losing weight” by being hungry or by limiting when you eat, you are losing weight because you are consuming less calories.
The same was cited in the article. The chess players are forgetting to eat.