Hey guys,
What is your secret for being an energetic person?

I have 8 hours of sleep, I can drink coffee, I can exercise and at 3pm - 6pm I nearly always feel low on energy.
I always think about top industry CEOs, chairmen, etc. how do they keep the pace?
I am still young but I don't have energy. I can't stay asleep after 1am

Do you guys have secrets that you can share with me?

Must mention: I tried to change my diet. I stopped eating carbs except for Sunday when I can eat whatever I want. For the first three weeks I used to get up very earlier and be full of energy but, now I'm back to normal. Now I eat just twice a day (breakfast + a meal at 4pm therefore I don't have lunch or dinner). Could that be the reason I am out of energy?