Guess you gonna find out!
But really… that’s my honest answer. Should be fine to do so, but everybody is different so… best thing to do is just try and find out for yourself! You will probably have more energy, just take your electrolytes and you should be fine.
I work out every morning at 6 am with no food, just black coffee, 5/6 days a week, 45 mins to 1 hour cardio or intense weight training. No energy issues after about a 3 month adjustment phase. Just take it easy. Your body will adapt. I don’t eat until noon. 18:6 is the norm.
You’ll crash out. You’ll struggle for energy you’ll, etc… the method of trial and error will show you the path.
The goal is to be come fat adapted. It took me years to get there. I am pretty much carnivore with fruit. But after 3 years of IMF and TRF, I was able to reprogram my body (and stomach). I can definitely tell the difference between “I’m hungry” and hunger. One is a Pavlovian reaction to food from chemicals released from the stomach, and one is my body telling me it’s time.
The difference is real.