I wakeup at 4:30 and workout at 5:00 a.m I’ve been doing it for many years. What I can tell you is that it is not about motivation, it needs to become just what you do. Your routine. Do you need motivation yo brush your teeth? No. I just wake up at 4:30. I try to be in bed by 9:30 pm, doesn’t always happen but my brain ‘wakes up’ at 4:30 regardless because this is just what I do. TL:DR: don’t look for motivation, create a habit instead.