For me, as long as I don't stop, my energy stays high! But, I do also eat very nutritious, low-carb meals, make sure I feed myself frequently with healthy snacks (yogurt or piece of fruit), and exercise. I wish I had time to exercise more, but only make it to the gym 2x/week, but I'm very active with my children the rest of the time and try my best to build exercise in naturally (walking up the stairs instead of taking the elevator, etc) Oh, and sleep! I've never been one for coffee, but I think like any addictive substance it probably makes you have ups and downs. Good luck!