I respect that advice and think it is sound for most. I've been an endurance athlete without interruption for close to 5 decades now and my strength has always been my ability to handle volume and recover fast. I've watched for deterioration in that ability over the past 10 years and know the signs. The biggest change so far is that I need a little bit more sleep...30 mins extra makes a huge difference for me. When I add sleep-in days, I get back on track almost immediately. I also can't do as much high intensity as before. I've made these accommodations and will continue to do so to extract another decade of racing out of this old bod.