The challenge

The challenge with the Breca Swimrun race is fuelling your body with food and water. The unique concept of dipping in and out of the water, along with running means nutrition isn’t as easy as keeping in your pocket, on your bike frame, or carrying a bottle like other endurance races. I want to dive into the practical applications to this race, picking from all my experiences of other ultra-endurance races.

Days before

A carb-load is highly recommended for such events like this. The easiest and most effective way to do this is to taper down (reduce) exercise output in the week before the event, whilst maintaining and gradually increasing your carbohydrate intake. This may lead to you having around 10g of carbohydrate per kilogram body weight, per day.

This technique will help you store more glycogen in your body (in your muscles and liver) and might be the difference between finishing the race or not!

If you’ve done this before you’ll know the side effects; perhaps making you feel heavy and bloated, but ultimately see what works for you. It might be 5 days or 2 days, but doing some version of carb loading is advised.

Morning of the race

Eating familiar food is important to prevent any unwelcome gastrointestinal issues. Choose your normal breakfast food (which is likely higher carbohydrate, with protein and some fats) but ideally have a larger portion than normal.

Hydrate with water. Remember you wake up dehydrated so getting fluid down you in the morning is crucial.

During the race

Working on the basis of ‘carbs per hour’ you need to think about where the checkpoints are, and what you can carry, and how much food you can handle on the move.

Ironman athletes aim for 90g carbs per hour (but in reality typically get 50-60g per hour). Taking into consideration these athletes have much better access to food (around their waist, on their bikes, in their pockets, in their drinks bottles) the Breca Swimrun poses a challenge. Picking up the foods on the stations to see you through the following hour can be done, it may mean stopping for 30 seconds at the station to feed, or grabbing multiple items to consume whilst on the move (think about your stomach and if you can handle this).

Having a dense high carb gel or bar on your person would also be advised. This might also contain caffeine to give you that extra boost when you might need it. Caffeine is a well-known and used (and legal) supplement in endurance sports, it can stimulate muscle fibres and can also reduce your perceived pain - very useful for those tough hills!

Fluid during the race is also important. You could be losing about 1 litre of sweat per hour, so trying to replace that is important. Losing <2% of your body weight through dehydration will impair your performance. So take your time at checkpoints to get the fluid in, and use the additional drinks like flat Coke to help with sugar and caffeine too.

Key messages

  • Trial the foods in training; find out what will be on the stations and get used to training with these.

  • Think about the carb load which will work for you.

  • Learn how to grab and go with food on the move.

  • Feel confident about your water intake and where you will get it.

  • Seek guidance on any supplements you think might be useful for the race.

About the author;

Kit Chamier is a Registered Sport and Exercise Nutritionist based in Jersey. Kit works with athletes of all levels to help them train and perform at their optimum. 

He is based in multi-disciplinary sports medicine clinics and can also conduct 1-1 sessions on Skype.

See or visit True Food-Sport Nutrition on all social media channels to find out more.