Ultrarunning: 100 Miles in a Week

August 15, 2011

This article is part of Endurance Planet’s ultrarunning article series. If you have questions, comments or feedback about “100 Miles in a Week”, please leave it below in the comments section…

Have you ever accomplished a training mileage of 100 miles in a week? You may have heard of ultrarunners doing well enough in 100-milers with less. So you’re probably wondering if this kind of mileage is really necessary.

The following is an overview of the considerations involved in such a training goal. Hopefully it will help you make a more informed decision and weigh the benefits and costs more carefully. As you deliberate about whether or not to establish this distance goal in your training, keep in mind the ‘experiment of one’ principle formulated by the late great Dr. George Sheehan.

100 is just an average number

Let’s say it’s the end of the week. You take a peek in your training journal and see that you’ve only logged in 95 miles. Do you go out and run one more time to make up for the lacking 5 miles? Is that extra 5-mile workout actually going to make a difference? It’s easy to fall into the trap of simply focusing on such a nice round and even number. Perhaps the more important question to ask yourself is how you ran the miles you’ve already put in for that week.

Endurance is a product of quantity and quality. Were you able to set a good pace? Did you run on the right kind of trail and elevation? Were you able to consistently maintain good form? Don’t worry too much if you didn’t hit the 100 mile mark. There’s always next week or the one after.

Build up

The obvious benefit of high mileage training is better endurance and, as some veteran ultrarunners point out, better finishing times in shorter races. The obvious cost is injuries from over-training. This can be mitigated however and the solution is simply to build up to that training goal.

Attempting to jump right into a 100 mile week from a 40 miles-per-week base is certainly a formula for disaster. The often suggested approach is to increase your mileage by no more than 10% every week. It will take several months before you reach that training distance goal but you’ll get there with minimum pain and discomfort. ‘10%’ by the way is also just an average number. For some runners it could be too little while for others it could be too much.


Once you’ve built up to a 100 miles in one week, the next question would be how often you should do it. Some elite runners actually accomplish it every week. Others maintain a slightly lower weekly mileage (70-80 miles) then move up to that distance as the ultra event comes closer. Unfortunately, the average ultrarunner doesn’t always have the time to run three times a day and still do long runs in the weekend.

Doing it once a month could be a viable training schedule, if your lifestyle and body allows for it. The first week is the shortest mileage and also works as the recovery week. Increase the mileage significantly on the 2nd, then lower it again on the 3rd – somewhere between the mileage of the 1st and 2nd. Then on the 4th and last week go for the 100 miles. This ‘easy-hard’ pattern is also applicable within the days of the week where you divide up the total mileage.


Do you have questions about running 100 miles in a week, or what you’ve read so far? Do you have any ultrarunning pointers of your own to add? Please leave your feedback, comments and questions below, and we promise we’ll respond.

Comments (3)

  • Runner says:

    Can we get a bio of the author? Experience? Ultras run? Etc.?

  • dvd ripper says:

    Hi, just stumbled on your page from reddit. It’s not an article I would typically read, but I loved your perspective on it. Thanks for making a blog post worth reading!

  • Runner says:

    Can we get a bio of the author? Experience? Ultras run? Etc.?

    I asked that back in August. No reply. I really want to know who is giving us this advice.

    And, maybe you can clean out the comment spam from DVD Ripper.

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