You ran how many marathons!?
Often times I'll hear people talk about how many marathons they raced last year. I am amazed at the fact that many of them will run 4, 5 or more in a year. Let's take a look at why you should only be running 2 per year.
Each 16-20 week block in my opinion can be referred to as a "season." The goal with any training is to continue to build off of each season to where each year we continue to get faster and improve. All of us know the stress that we put our bodies through when training for a marathon. What I find is many people neglect other energy systems when they decide I want to run marathons. It's very important to alter the race distance so that your hitting the anaerobic side of training as well as the aerobic. Here's an example of how a year might be laid out.
September through December - Marathon Training. This will include an increase in mileage along with improvements in the aerobic development.
December through January - Recovery. The harder we train the more time we need to devote to recovery. But don't worry, your not going to lose fitness from taking 3-5 weeks of easy running as you slowly build your mileage back up. During this time we need to focus on strength work, be sure we don't neglect the leg turnover work either. Strides and hill sprints are important to stay sharp.
February through March - Short 4 week speed phase. Get out there and race a 5k, want to see what you can run for a mile? This is the time of year to explore some of those odd race distances. As you transition towards marathon training again, your MP workouts will feel easy compared to those 5k pace workouts.
March through May/June - Marathon Training.
June through July - Repeat the 3-5 week recovery plan described in December through January. Maintain leg turnover.
July through September - Similar to February through March you will want to train for those shorter race distances but don't shy from the moderate distances such as 10k, 15k. With the increase in speed work and hard tempo's you will improve your V02 max before transitioning to longer slightly slower paces during your Fall Marathon.
This schedule can be altered to fit your seasonal marathon season. Here in the Southeast nearly everyone has to be done with their marathon training by June due to the extreme heat and humidity. For those in the Northern Rockies it would make more sense to have an early summer marathon followed by a late fall marathon due to the extreme winters. Wherever you live just be sure to arrange your seasons accordingly to give yourself the best chance for success.