Let me put my n=1… I used to do early morning workout, but now reverted back to evening workout. First I choose early morning workout and did well for some time. Wake up 5AM, start workout around 5:10~5:30. Before 7AM I finish take shower and prepare to go to work. Sleep 10PM. But my kids doesn’t guarante me a nice sleep time. Even one of my kid has condition of CP and he sometimes sleep late, sometimes wake up early. This life inconsistency keep me from early morning workout.
Now I do my workout as soon as all my kids go sleep. I maybe sleep late, but due to covid19 outbreak now I can work at home. Time saved from commuting returns as my sleep time. This enables me to do workout more consistently even it’s late evening workout.
Oh, there was one more reason I chose early morning workout before. Last year I used over estimated FTP value with ramp test on my training. That makes my training into threshold training at minimum. There was virtually no sweet spot training for me and my battery(W’) might be significantly drained for every workout. If I do train late at night, I cannot sleep because of all the excitement/heat in my body. Warm/Cool down didn’t work for me. Because of that experience I thought early morning workout would help me sleep better… Now I estimate my FTP value using Kolie Moore FTP test protocol and now I don’t have problem getting into sleep after late evening workout. If someone should to his workout late evening, one’s FTP should be appropriate or under estimated at least. If you cannot fall asleep after night workout, there might be chance ftp be over estimated.