Daniels’s approach is not the only approach to determining how long runners train for specific events. For example, Brad Hudson uses a nonlinear periodization approach that mixes the various types of training together more than the Daniels system does. Hudson believes in maintaining a high level of aerobic fitness and speed year-round in his runners, so that they require little time at all to sharpen up for peak performance. His marathoners typically devote only 12 weeks to focused preparation for their big races. The higher your starting fitness level isin other words, the closer you are to peak fitness when you begin focused training for a peak racethe more you risk burning out before your race if you plan a longer training cycle. Hudson’s runners would likely become overtrained if they trained longer than 12 weeks for a marathon, so fit are they at all times. Indeed, Hudson blames an overlong training cycle for his former star client Dathan Ritzenhein’s poor performance in his debut marathon. You can intentionally delay a peak when necessary to avoid overtraining, however, by holding yourself back in your workouts until you reach a point where you can ramp up steadily without a high risk of burnout. Suppose, for example, that you are 15 weeks away from peak marathon fitness when you decide to run a marathon that’s 20 weeks away. In this case you could train relatively lightly for the next 5 weeks and perhaps focus on types of training that will make your body more resilient when you begin ramping up 15 weeks out from race day. Naturally, this sort of calculation works best when you are able to accurately judge how close you are to peak fitness in terms of training time. This ability comes with experience, but nobody ever perfects it. There are simply wild guesses and informed guesses. In the end the best you can do is commit to a schedule that seems sensible and make adjustments as you go.