Training for a mountainous ultramarathon (!)

THANK YOU FOR VISITING SWEATSCIENCE.COM!

My new Sweat Science columns are being published at www.outsideonline.com/sweatscience. Also check out my new book, THE EXPLORER'S GENE: Why We Seek Big Challenges, New Flavors, and the Blank Spots on the Map, published in March 2025.

- Alex Hutchinson (@sweatscience)

***

In the comments section of another post, a reader posed an interesting question about training for an upcoming ultra-marathon (not just any ultra-marathon, mind you: the fabled Canadian Death Race!).

I am training for my first ultra-marathon, the 125km Canadian Death Race. It takes place in early August. My weekly long runs are reaching marathon distance. I’m curious about a couple of things:
1. Understanding that it is unrealistic to train to 125km, what is a realistic distance to train to?
2. Considering I have another 4 months of training ahead, should I peak at marathon distance, taper, rest and then build up to train past that distance. Or should I aim for consistent long distances for the remaining months?
Any help would be appreciated. Thanks for your time.

These are some good questions — and ones that fall outside my area of expertise. So I figured I’d try to rope in a real expert to offer some advice. Derrick Spafford is a hardened ultra vet and experienced coach (readers of Canadian Running may remember Spafford whizzing past editor-in-chief Michal Kapral in his account of the Rock and Ice Ultra [10MB] last year.) Here’s what he had to say:

It does sound like you have built up to a very good level getting in up to the marathon distance for your long run. You haven’t indicated if these are mountain miles that you have done or flat miles…big difference obviously. Not knowing what the rest of your training has involved, it is tough to give you the best answer to your question, but here are a few guidelines that you may find helpful.

1. For your long run, I wouldn’t be too concerned with distance, but just getting in the time on your legs. The length should be a gradual progression that is slowly increased with your longest run being about 3-4 weeks before the race. Building up to between 6-8 hrs for your long run should be the goal for completion, and this can include regular walk breaks while hydrating, refueling or on difficult climbs. During your buildup it would be best to also incorporate back to back long runs too. These offer the benefit of getting in some long hours over the weekend, but are not as demanding and are easier to recover from. A back to back long run weekend could eventually look something like Saturday 4hrs/Sunday 3hrs. Alternating between a single long run on one weekend and back to back long runs the next weekend works well. Then be sure to add a recovery week every 3-4 weeks.

2. Since you are already up to the marathon distance in training, I would encourage you to sign up for a Trail 50km in May/June, then take a few weeks to recover before your final buildup towards the Death Race. Getting a shorter trail ultra under your belt will give you a chance to fine tune your nutrition, gear and give you confidence for the big one.

One final piece of advice is to be sure to get some time in on the hills or mountains. This can be done either by running hill repeats, continuously run up a mountain, or doing continuous uphill runs on a treadmill. These also need to be increased very gradually though. Practicing some downhill running is equally as important as well to help strengthen your quads for the continuous braking action of descending.

I hope this helps.

Needless to say, this sounds like excellent advice. I particularly like the idea of alternating single long runs with two-day “long-run weekends” as a more tolerable way of getting in time on your feet. And I can also attest to the importance of getting in training on the hills. I just did a mountain race for the first time last weekend — a very short one, but the downhill absolutely ravaged my legs. I definitely couldn’t have kept going for another 120 km!

Thanks to Ben for the question, and to Derrick for taking the time to offer his expertise.