NUTRITION FOR ULTRAS
In previous threads on preparing for UTMB and lessons from UTMB I only touched briefly on nutrition.
In this thread my intention is to pull together a range of resources and ideas to assist with nutrition for ultramarathons.
Nutrition is a difficult topic because there are evidence-based recommendations, but they are not always followed.
In this paper we see that elite athletes did follow guidelines (71g/hr CHO):
Outside of these studies and guidelines we see athletes succeeding in endurance events using a wide range of different nutrition strategies. Maybe a good starting point is to ask:
1) WHAT'S POSSIBLE?
There are examples of athletes succeeding with nutrition strategies ranging from very low CHO to very high CHO, from all-liquid sports nutrition to only real food, from carrying their own nutrition to only relying on aid stations.
The context of these different results and different strategies is quite important and can contribute to defining what is possible:
1a) modality - eating and digesting is easier in cycling compared to running and easier in running compared to swimming.
1b) duration - eating a certainly hourly rate is easier in a 4-5 hour event or as an elite running 14hrs at Western States compared to an amateur at UTMB or an athlete during a 24 or 48 hour race.
1c) accessibility - food availability for an elite with a crew or an athlete at a 24 hour race is very different to a self-supported athlete at an ultra with few aid stations.
Clearly "what's possible" may not always meet the recommendations even if that is the goal.
Race nutrition should also follow the "work required" paradigm. A shorter ultra at high intensity may necessitate more exogenous CHO intake than a long, low-intensity ultra where fat oxidation can be relied on more heavily.
3) TRAINING NUTRITION INTAKE
If the logistics of the race allow it, and the intensity demands it, then using a high CHO approach can be the right solution. However, our gut needs to be able to tolerate this approach.
Race nutrition during a 24hr run:
"In-race CHO intake was only in the 30–60g/h range"
"Strong to moderate positive correlations were observed between distance covered and both CHO and energy intake"
Alternatively, if you want to increase your fat oxidation to use a lower CHO approach you will also need some adjustments to your diet and training nutrition. This guide suggests that may be more beneficial than training the gut:
Whichever approach you choose, it's important to make sure that you do the training necessary for that approach and that you don't do something new on race day.
4) HIGH CHO + EXAMPLES
The potential to use a high CHO approach in mountain ultras along with the benefits were shown in this paper:
There have also been many examples of World Tour cycling teams using up to 120g/hr CHO.
Petter Engdahl shared his CCC nutrition and he consumed ~120g/hr of drinks and gels:
Tom Evans reported that for UTMB he used ~95g/hr of mostly Maurten and Red Bull.
5) MID-RANGE CHO EXAMPLE
According to the data shared in this post:
My calculation for Kilian's nutrition during his races this year was:
Hardrock = ~55g/hr
UTMB = ~75g/hr
6) LOW CHO EXAMPLES
Zach Bitter has reported using 40g/hr during his races (primarily 100mi).
Jeff Browning has reported using 40-50g/hr during his races (primarily 100mi).
Dan Plews reported using 50g/hr during the bike and a total of 40g during the run in Kona.
7) RESOLVING GUT ISSUES
Nausea and/or vomiting is the primary cause of a DNF at ultramarathons:
Therefore figuring out a nutrition strategy that works for you is vital.
8) PRACTICAL TAKEAWAY
A good place to start is the evidence-based recommendations of 60g/hr CHO.
If you know the intensity of your race is going to be high and you have access to your own in-race nutrition, considering increasing CHO intake.
Increasing CHO intake will require training and practice at race intensity.
We've seen up to 120g/hr for a 10hr ultra and up to 95g/hr for a 20hr ultra are possible.
If you're having stomach issues or the pace of your race is lower...
...consider either trying to resolve these issues using the Athletes' Gut book (mentioned above) or start working towards a low CHO strategy. Again this will take training and time to develop.
All of the points in this thread, along with the information from the previous two threads on preparing for UTMB, can be found on my blog:
I hope you find this useful.