Anne-Marie,
I stopped radiation about 5 months ago. On weekends I prefer to sleep 12 hours a night and during the week I sleep about 10. During my waking hours I have all the energy I've ever had. I know this wouldn't be true if I wasn't going to bed at 8:00 PM. I am working full-time although for the first time in decades full-time means no more than 40 hours. I'm not an exerciser, but can say that a weekend bike ride seems to give me energy for the week. I think it's part of feeling alive again. Last week I rode 15 miles along a beautiful flat coastal path. I also found a daily cup of coffee makes a huge difference. It's funny how before I could hardly tell if I drank 3 or 4 cups. I strongly recommend making time for sleeping. It's hard to do, but I really think it's what allows me to fully function during my waking hours. I've been trying to take vacation time at least every other week too. This allows me to not have my schedule so full that I can't get to bed on time.