Thanks guys. I do 30-40 minutes of HIIT on my road bike. There's not really any hills, but I just kick the intensity up and down.
By the way I've been doing this eating plan for three days now and I LOVE it. It's some kind of fucking magic, man. I'm staying full on as little as 1500 calories a day. I've been plateaued on fat loss for weeks trying everything, and I've already lost a true 1.5 lb since doing this plan. It's SUCH a great idea. The fasted hours really aren't that bad since I've never had an appetite during the day anyway, and I'm eating the same at night as I used to when I had breakfast. During the fasted periods I load up on coffee and I'm good. LOVE this shit!
Keep in mind that, if youre doing HIIT, I wouldnt be surprised if you plateau again soon. HIIT is hard enough on the body that it should be considered an actual lifting workout.
As much as it goes against everything youve heard, try cutting out the cardio for 2-3 weeks and just focus on lifting 3-4 times a week. I know you probably dont believe itll work, but you probably didnt believe that fasting for 16 hours a day was a good idea either, right?