Why long run mileage varies in training plans

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Steve asks: I’m preparing to train for my first marathon and have been searching for a training plan. My question is about the long run mileage because I see some plans just go to 16 miles, while others build to 20 or even more. Which one is best? How do I decide which plan to follow?

Yes, there are many, many different marathon training plans to follow. If there were just one training plan for all, it would be similar to having “one size fits all” clothing.

Different training plans are necessary because of the vast differences in individual fitness levels, running backgrounds, ages, health and running goals. And, to complicate matters, fitness levels, needs and goals change over time, so a plan that worked for you once may not be the best plan for you again.

Here are some things to consider when selecting a training plan. First and foremost, assess your fitness level going into training. Take an honest evaluation of how many miles a week are you already running and compare that to the starting mileage of the plan you’re looking at. Then, consider these contributing factors as well:

  • How long have you been running?
  • What is your longest run to date?
  • What is your overall heath?
  • Do you have any health issues or orthopedic problems?
  • What is your age?
  • Do you have a history of injuries, specifically running injuries?
  • What is your goal for the marathon? (Just finish? Hit a certain time? Qualify for Boston?)

That said, for first-time marathoners, I suggest following a three or four day-a-week training plan that builds to 20 or more miles. These plans typically have one 20 mile run and a few weeks later a 22 or 23 mile run, followed by a taper to race day.

Three day-a-week plans allow runners an automatic built-in recovery day by having the day off after each run, which is very important for first timers. I also prefer the longer mileage plans for new runners primarily because everyone has heard horror stories about the dreaded “wall,” and many runners fear doing distance for this reason. Long runs help train the body and the mind for these specific rigours of the marathon distance.

Figuring out the right running pace to get through longer outings is the other reason I often suggest higher mileage plans for first-time marathoners I train. Many of the training runs will be a new distance for you, so to reduce the risk of physical stress that might lead to injury or burn out, most plans encourage new runners to slow down. Your long runs should be run at a very comfortable, conversational pace. By running slower and longer, you will greatly expand your aerobic endurance base and build the confidence necessary for covering 26.2 miles.

After completing your first marathon, you will have gained the benefit of a huge endurance base and a conditioned body. The next time you train for a marathon, you will be able to increase the intensity of your training runs, and you’ll have a better idea of what your goal marathon time might be.

When marathoners are able to train closer to their goal race pace, they can opt to cut back on some of the longer 20 or 20-plus mile runs, substituting intensity for distance. This allows you the option to consider trying one of the shorter mileage training plans for your next marathon - because who can do just one?

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