I did my induction 2 weeks strickly by the book an I found that I was very tired for most of it. I did get more energy at the very end. Since induction, I feel great, have no carb cravings, and am extremely glad I decided to do Atkins. If this is the plan you want to use, you need to stick with it for the 2 week induction. If exercising for your vacation is the priority and you are too tired, life is going to be miserable. Perhaps you need to do something else until after you get back from vacation, then do Atkins right. I am sure you will find that you feel really good after 4 or possibly more days. While you are doing this, rest a lot and don't do any more than you must.