A quick search on tells me there are. I am speaking from personal experience. If I do an intense workout and don’t eat within the next few hours I get anxious and depressed.

Took me a while to realize that diet was the culprit; but after a lot of self experimentation I am 100 percent certain.

It has to be highly personal, I cannot eat after a gym session, but I feel better than ever. I often train fasted and stay fasted until my evening meal

I am the same, morning workout with protein shake then evening meal. Everyone is unique.