21 October 2022


Becoming an ultra-runner does not happen overnight, and it takes several years of continuous training.

Tomas Amneskog, Team Arduua runner is currently preparing for Kullamannen 100 miles, that will take place in Sweden 4 November this year.

Tomas has been taking part of the Arduua Elite Coaching programme now for a couple of years, training with coach Fernando Armisén, and he is very passionate about his running.

We asked him in general terms in how he prepares for a race like that, and you can read more about it in this blog.

Blog by Tomas Amneskog, Sweden, Arduua Frontrunner.

The basics

First of all, you need to train continuously for some years to run races this long, and you don`t start with a race this long. The path to 100 miles mountain races goes through half-marathon, marathon, ultra-marathon, 50k, 100k. And training for races this long is not so different than training for 50k races. At least when it comes to the physical.

A good endurance base with a lot of miles in varied terrain, spiked with high intensity to build a strong heart and anaerobic capacity. The polarized training (80/20).

I do long runs every Saturday, and have done so for the last 7 years. To begin with, my long runs was 90 minutes, then 2 hours. Now they the typical long run is 3-4 hours on trails, and usually I go 30k with around 1000m+.

These are my social runs with friends, where we explore and have fun. We sometimes go a bit longer, up to 50 k, but still with an easy pace. I like to maintain this level during the entire year. I combine this with 4-5 shorter runs during the week, where some have higher intensity depending on which period of the year it is, and what races I have coming up.

The specifics

Normally, when you have a shorter race coming up, you need to get the body used to the race specific pace. For half-marathon and shorter, this is a few clicks above the threshold, for marathon, just below. For a Sky-race, vertical speed up and down, and for a Trail-race, speed in technical terrain.

But when it comes to 100 miles+, the race pace is the same or slower than your normal recovery pacing, so there is no use in training for that. Just get the miles in and do it continuously. There are other factors that are more important than speed when it comes to long ultra-races.


Train your stomach. Many people fail because they cannot take in enough energy. And if you haven’t trained to take in energy during long activities, you will fail. Of course, you can still finish the race. I have had stomach breakdowns and went on for 8 hours without being able to eat or drink anything. But it isn’t fun, and you are really slow.

So, now I train with carbohydrates on all my long runs. But to start build your body’s ability to take up the energy, you need to focus your training for at least a couple of weeks, where you take in energy on every training session that you do, even the short ones, and definitely the ones with high intensity.

Start with a low dose of carbs, and increase it until your stomach feels upset, back down, and start to increase again. I have of course tried keto diets on my ultra-runs, but you’ll be able to run faster for longer if you can take in a lot of carbs. Nowadays I drink my calories and eat only when I’m hungry.

The mental

This is the most important part. The first time I ran 90k, I learned that anyone who can run 10 k can run 90 k. You just need to want it really much. For me, distances up to 100k is within my comfort zone. They are manageable, and most times runnable all the time. But when you go longer, you will have downs. Really deep downs. Where you just have to focus on putting one foot in front of the other. When you cannot run and need to walk. And when every step you walk is pain. That’s when you have to push through, and know that it will get better, because you’re at rock bottom.

This is not anything you can train on if you’re not experienced it in a race. But there are some tricks. Hill-repeats are one thing. Slow hill repeats for 4-6 hours is food mental training. Running in bad weather. Running at night. Train to be uncomfortable. And never give up.

Ultra tapering

The last week before a long race, I focus on feeling good. Slow, short runs, sleep a bit extra, eat well, and pack your gear one week in advance. Then you don’t have to worry about not having everything that you need for the race. And plenty of time to add or remove things.

Take care of your feet. I trim my toenails really short and rub my feet in Sheabutter every night before I go to sleep. The last day before the race I do a little bit less fibre. Before I became full time vegan, I used to eat plant based the last 3 days before the race, and performed a lot better, feeling lighter and faster.

/Blog by Tomas Amneskog, Arduua Frontrunner

Please check out Arduua Coaching and How we train for more info…

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