Alister Gardner running up Mont Bromont during an Everesting challnege accompanied by some cheering friends

Bromont Ultra Race Fuelling Guide

By Alister Gardner - 5-7 min read  

What better way to spend your long Thanksgiving weekend? The Fall colours are peaking and the trails are calling!

Whether you are a rugged, seasoned ultra-running veteran or just dipping your toe in trail-running for the first time, fuelling yourself properly is the key to a happy, good race.

To get started, here are our top 5 tips for your race this Bromont Ultra weekend:

  1. Your training should be as much about developing your nutrition strategy to be ready for race day as it is about developing your physical fitness.  By getting to know how your stomach reacts to different foods and how they help your energy levels, you can better develop your race day fuelling strategy.
  2. Start fuelling early.  Don’t wait until you are hungry or feeling like your energy is down.  By getting a few calories into your body early on in your race, you’ll be more likely to avoid bonking, plus, you will keep your digestive system active.
  3. Eating a little something more regularly is better than big feeds that are spread out.  Your digestive system will remain active so it will help you avoid digestive issues.
  4. Carbs are key (and always have been). There have been plenty of fashion diets that have come and gone but our muscles burn glucose best when it comes to moderate to high intensity exercise, and the best source is carbohydrates.
  5. Fats and protein come in handy when it comes to many hours out on the trail to the point where you’ll be missing meals.  Protein consumption will help avoid the body using its own protein (muscle mass) as a fuel source while fat  will be burned slowly alongside the carbohydrates.

During the days leading up to the race..

For the two to three days prior to the race, you should aim for meals containing plenty of carbohydrates so that you can build up your glycogen reserves. Glycogen is what gives us the energy to run faster for the first 60 to 90 minutes. When those reserves are depleted and you start to feel sluggish, or even dizzy from lack of energy, this is called 'hitting the wall'. This is where energy gels and bars like XACT Energy come in handy!


Fuelling guide for the 6, 12, 15 and 25 km races

 In short: Simple carbs and sensible hydration.

 The harder you run, the more energy you burn and so you should aim to consume your carbs more regularly. 

XACT ENERGY fruit bars are the preferred choice of many ultra marathoners that have completed the challenging courses of Bromont Ultra

If you have a rough idea of the time it will take you to finish your race, you can use the table below to plan your fuelling strategy and know how many Energy bars you’ll need:



Every 30 mins. 

Every 45 mins




2 1h 1h30
3 1h30 2h15
4 2h 3h
5 2h30 3h45
6 3h 4h30
7 3h30 5h15
8 4h 6h


While your fuelling strategy should be the same whatever the weather, your hydration strategy can vary a lot depending on the heat and humidity on race day.

XACT ELECTROLYTES can help maintain adequate hydration during sustained effort

If you're running for more than 2 hours in hot weather and drinking a lot, aim for fluids with electrolytes. 

The more you sweat, the more you will need to replace those fluids, and the more important electrolytes become. 

Hydrating with many litres of water alone can lead to hyponatremia (a problem where your blood-salt level is too low). 


Energy bars with added electrolytes, salty foods and salt tablets can help, but by drinking fluids with electrolytes already included is one thing less to think about and your fluid absorption will be improved.


Aid station notes - 6, 12 and 25 km races:

  • On the 6 km course there are no fuelling or water stations: you will have to be 100% self-sufficient
  • On the 12 km course there are 2 water stations. If you think your race will take over 60 minutes, bringing fluids and fuel with you is a good idea to supplement your run.
  • On the 25 km course there are 2 water stations plus a full aid station at the 15th km. This station will be a handy spot to refuel as there is still one large climb up Mont Gale.

55 km Aid station notes

 Despite the massive distance, the fast runners will be adopting a non-stop or minimum stop at feed stations; using energy bars and gels at regular intervals and not spending time resting at feed stations.  However, for most runners, it will be 8 or 9 hours out on the trails.  This means a slightly different nutrition strategy.


"Ideal amount to consume ..."

Your main source of energy will still be simple carbohydrates. Again, the ideal amount to consume is 100 calories every 30 to 45 minutes. However, the idea of eating nothing but 15-20+ energy gels is probably heavy going for some (if not most) runners, so it will be handy to take advantage of the variety of foods available at the feed stations.  Salty chips, potatoes and broth will be a welcome change in taste to your primary fuel. What’s more, more complex carbs help you feel more satiated and provide additional, slower-burning carbs.  

" No need to rush through the aid stations..."

With so many hours on the trails, there is no need to rush through the aid stations (as you might do on a marathon).  Take a moment to eat and refill your hydration pack.  A couple of extra seconds fuelling at the feed station will more likely mean a better pace out on the trails, which will more than make up for the time lost.  Plus, a moment to chew will reduce the risk of indigestion.

 There are three feed stations and five water stations along the course.    

 Aid station notes: 

  • Feed stations are at 15, 32 and 48 kms, meaning a likely two to three hours gap between each one. 
  • Carrying your own fuel will be important
  • Using the table above you can calculate how many bars you will need. It might seem a lot but they are compact and portable, so a few more is better than not enough.
  • Hydration will depend on the weather. There are regular water stations so filling up regularly could make sense rather than carrying a full bladder or bottle from the start which means extra weight carried... 


80 & 160 km Races 

It will be an early wake up call on the Saturday with the 160 starting at 6 am and the 80 starting at 7 am.  This means an early breakfast.  It is an important meal as it will be topping up your carb levels ready for the day ahead.   You will be finishing your race either later that evening or well into the next day.  On a regular day you will have eaten two or three meals in that time and have done relatively little activity.  This gives you an idea of the thousands of calories you need to fuel your race.  


Simple carbs in the shape of Energy bars, gels and chews are a great way to get energy into your system fast, but as quickly as that energy comes it will go, so it is important to fuel often.  Regular and consistent intake will help control those ups and downs of energy but it also helps to mix in more complex carbohydrates, some fats and some proteins.  These will help you feel satiated as well as provide some diversity in what you’re eating.


It is worth noting that the ingredient maltodextrin is not a slow-burning carbohydrate source but actually has a higher glycemic index than glucose itself.  While rice, banana bread and pita bread may not be low on the glycemic index, they are still lower than glucose and maltodextrin and thus help you feel satiated while providing easy-to-absorb energy.  Salty foods at the feed stations will also help with your sodium intake as well as provide a welcome balance to the usually sweeter carb sources.

"Sodium intake is very important..."  

Sodium intake is very important during such long distances. Hydrating with water alone can quickly lead to hyponatremia and can slow down gastric emptying (that ‘sloshing around’ feeling in your stomach). So do not be shy to tuck into the salty foods at the feed station and use the electrolytes on the course.  You should also consider energy drinks with carbohydrates in them to help get more energy into your body, especially if you are having difficulty eating solids.


Drop bags (or if you are lucky, your support crew):

You may have a particular food that you have been training with or love to eat when you are hungry (ice cream!!) and your drop bag or crew can get it to you while you are on the course.  Drop bags are also a handy way of carrying smaller amounts of gels and chews over the whole course, and you can refill your pockets at the aid stations.


 Aid station notes:

  • There are 4 feed stations and 5 water stations on the 80 km course.
  • For the 160k there are 9 feed stations, with the addition of the base camp station at the halfway mark. 
  • With 15-18 kms between feed stations, 2-4 hours of autonomy are required. This gives you an idea of how much food you need to carry between the aid stations, keeping in mind that drop bags and crew are not at every station.
  • The nights will likely be cold so it will be important to plan to get your calories from food sources rather than to rely too much on fluids.

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