I do it all the time (exercising in the morning during the fast window). I honestly think it helped with the weight loss (especially high intensity interval training / cardio)
It honestly doesn’t drain my energy. I find it actually raises it the rest of the day.
During fasting.
You see it mentioned the 14th and 16th hours.
You could train in towards the end so that you could have a meal post workout.
Like the last hour or two, then right after jump on breaking your fast.
I exercise at about 18hours into my OMAD fast. I never had problems with energy. Been doing this for 6 years now. Thou I don’t OMAD everyday, maybe 3-5 times a week. It did take a little time to get used to, because I was so used to thinking I had to eat before I exercised. I do an hour of some sort of cardio, and lift.