Ultrarunning: Advancing to 100 Milers from 50

July 18, 2011

This article is part of Endurance Planet’s ultrarunning article series. If you have questions, comments or feedback about “Advancing to 100 Milers from 50 ”, please leave it below in the comments section…

To advance from running 50 mile ultras to 100 milers is definitely a big step. It’s one you can’t take lightly if you plan to finish. The following is a brief outline of some of the more important things to consider both during preparation and the event itself.

Before the race

The objective here is to help yourself adapt to the new conditions and challenges that a 100 miler will impose on you.

  • Long runs

One of the basic adjustments to implement is to increase your mileage. If you do an average of 25 miles to train for the 50 for example, then you probably need to do somewhere around 40 for the 100 miler. Gradually increasing the hours of continuous running is also recommended.

It would also help to do your long runs in consecutive days like during the weekends. You can split your target mileage between the two days. This simulates the conditions of the 100 miler which is split into two segments. The objective here is to learn how to keep reserves just as you would need to do in the first half of the 100 miler, and cope with fatigue just as with the second half.

Some veterans suggest that you schedule these back-to-back long runs 2-4 weeks apart, others say 5-6 weeks. This will really depend on your rate of recovery.

  • Running at night

Another notable difference between the 50 and 100 miler is that you’re going to be running at night. To fully appreciate this fact, try to do a night run. You can start sometime in the late evening and end it at dawn. Alternatively, you can try to do a 24 hour run without exactly setting a target distance. If you can manage it, do your night run on a trail similar to the race. The sooner you get used to running on a rocky terrain at night the better.

This is how the second half of a 100 miler is going to feel and look like.

  • Compete to train

Some runners join a series of ultras as a way to train. Each race event serves as a sort of training launch pad for the next one. Again you should schedule these according to how quickly you can recover. One suggestion is to join a 100 kilometer (62 plus miles) race 3-4 months before the 100 miler you’re aiming for. This will help test your fuel and equipment, as well as evaluate your physical condition.

During the race

You’ve done the training, time then to plan for the actual race. Areas you need to pay attention to are pacing, hydration and nutrition, keeping awake, support crew and equipment.

  • Pacing

Since it’s important to have reserves for the second half, you should start the 100 miler at an easy pace. It’s been said that the 100 miler is just like the 50 except you go slower. Well you certainly need to incorporate some walking in such a race, particularly in uphill situations. Some veterans even advise to only do the same amount of running as you would in a 50. If you manage your pacing well, you’ll have enough energy to make it through the second half and all the way to the finish line.

  • Eating and staying awake

Because it’s a far longer race, your body is naturally going to need more fuel to keep going. It’s not necessary to go exclusively for special supplements like PowerBar Gels. Regular food you take when not running can work just as well, as long as it was part of your training and your body is already familiar with the routine.

You’re also likely going to need caffeine as you’re going to be running long into the night. Some runners recommend you take this at night and decrease your pacing a bit so that you can get a resurgence of energy at dawn.

  • Crew and equipment

It’s certainly far safer to run a 100-miler with a support crew. The distance is just too great. Your team should be involved in training, even in the prior events you joined as preparation. Do you want them in front or behind? Do you want conversation / morale boosting? When should they remind you to fuel up or adjust your pace? Work out the system with your pacers beforehand.

You’re also going to need drop bags. Plan out the essentials and prepare them weeks ahead of the race. You’ve probably heard enough stories about runners dropping out because of some important medication or clothing left at home. Two items you must be sure to have in your drop bags are spare footwear and bright reliable flashlights. Blisters are one of the typical injuries that hinder runners and you don’t want to miss your footing on that dark trail during the second half.


Do you have questions about advancing to 100 milers, 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 (2)

  • Franklin says:

    Two questions:

    1. What kinds of solid foods should I consider instead of just energy bars & gels?

    2. When/if stomach problems start, what is a quick relief to avoid dropping out or suffering more?

  • 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!

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