This excerpt is from a forum I belong to that is everything to do with Clean Eating - Tosca Reno's Kitchen Table (http://www.eatcleandiet.com/the_kitchen_table/ )
It was posted by a member named Carolyn1213 who has lost 107 lbs, gained muscle and went from a size 22 to a size 8, all by eating clean and exercising! She wrote about a concept called "Periodization" used by athletes. It was the first I had heard of it and thought it would be worth passing it along.
"I want to spend just a moment talking about a concept known as periodization. This is something I have used for myself and for my clients and I find it to be very effective. Athletes use periodization. It is the idea of eating and training for the 'season' you are in. Professional athletes have on off season, pre-season, in season and post season. During these times, their focus and training are different for each phase to meet the goal of that phase. Runners, who strictly run and run year round tend to stay injured and have more difficulty with recovery and progress.
Likewise, those who are trying to lose weight, drop body fat and increase muscle, need to look at the year in quarters. Think of a large slab of marble. The tools that you would use to chunk off the larger outward sections is totally different than the tools you would need to use to chisel out the finer details. So, in weight loss, you have the beginning phase that is focused more on cardio and larger muscle groups and making the dietary changes along the way. Your plan has to ebb and flow. There has to be times that your purposely cause yourself to relax, pause, reassess your goals and the road ahead of you. This may shock you, but I have purposely put myself on maintenance to give my body (my skin and musculature) time to catch up with the changed that were taking place. Maintenance phase for me usually lasts 3 mths. then I start working on the next goal. During weight maintenance I focus on muscle gain, not fat burning. I want muscle to fill out the space that fat has left so that my skin has minimal sag."