4 Endurance race day nutrition essentials + free athlete nutrition guide.

If you want to know more about how you should eat as an athlete, then we have put together this comprehensive guide that is completely free to download.

The focus of this article is more to do with race day nurition and strategy. We will look at the 4 biggest areas of nutrition you should be considering before the big day, what you need to do and how you need to do it.

Your Individual Fuelling Needs:

The Problem: Race day fuelling is a balancing act between the duration of the event, the rate at which you use fuel at different effort levels and how much you have in your natural stores and how quickly you can take fuel on board.

For endurance sports lasting less than an hour, most people have sufficient energy stores to maintain their race pace. However, for some, larger, athletes the rate at which they use fuel especially at higher intensities can drain the battery quickly.

It is likely that for very long endurance events the fuel tank will be depleted, and depending on how you have practiced fueling during training this may happen quicker than you expect, especially if you race harder than you have practiced in training.

The Solution: Aside from making sure you have fueled properly before the race (see below), and that you are going to be racing for over an hour. Then as a basic guideline then you want to hit at least 60g of carbs per hour, from easily digestible sources like gels or sports drinks.

If events are longer than 2 hours, then chances are you are going to want to maximise your carb intake using specialist sports drinks that contain a blend of fructose and glucose that allow you to take on board up to 90g per hour… assuming you are working at a consistent, threshold race pace. You will want to practice this to make sure your gut can handle it, otherwise accident will happen.

When we enter ultra-distance events, we then need to focus on not just carbs but also calories. Chances are that although you will need some carbs for performance and cognitive function, in these events the priority is consuming more whole foods and a focus on overall calories rather than carbs alone.

If you wanted to get highly accurate with how much you need then performance testing for VO2 max can also give you detailed information of your calorie and fuel usage at different effort levels to create an individualised race plan.

Timing Your Nutrition:

The Problem: It’s the night before your race and you know you should be fueling up, but you don’t feel hungry. To make matters worse your race is an early start… should you have breakfast? If so when and what should you have?

The Solution: The good news is that as long as you have fueled sufficiently in the few days before the race you don’t need to eat a big meal the day before or even morning of the race.

This doesn’t mean you shouldn’t load up on carbs. But you do not need to do this the day before. The reason for this is simple. Assuming you are resting the few days before the race then you won’t be signficantly depleting your glycogen stores.

Think of it like filling the petrol tank of your car for a long drive. Assuming you have filled it to the brim, and you are only doing a few errands the day before, you only need to top up the fuel tank before you set off on your epic road trip.

Your brain and certain cells in the body will use up stored forms of carbs even when resting, but your muscle glycogen and your stores in your liver aren’t going to get even close to low levels just doing day to day tasks and topping up your stores with a few carb rich meals the day before.

This also means on the morning of a race, if you don’t feel hungry, then something quick and easy, like fruit or some toast will do the job. It also means if you are racing later in the day then you can eat normal balanced meals rather than having to stuff down a lot of food.

Many of our athletes prefer to do their fueling earlier than would be typically fine, and even over a couple of days, if they struggle to consume enough food. If you can take onboard 10g/kg of bodyweight over a couple of day period, and are fairly inactive, then your fuel tank will be full to the brim.

Electrolyte Replenishment.

The Problem: One of the most poorly understood and potentially dangerous areas of performance nutrition is electrolyte depletion especially when combined with lots of fluids.

As we sweat we lose electrolytes, sodium in particular, but we also deplete other in the body. These have many essential roles in the body that effect performance and many athletes vastly underestimate the effect that becoming depleted can have on performance.

Combine sodium losses with ‘smashing’ in lots of fluids on hot days, can lead to severe ‘dilution’ of sodium in the body and this can be fatal. Not so be sensationlist, this is rare. But it can happen especially when you are looking at being out in the heat for several hours.

The Solution: People sweat and lose sodium at different rates. There is some testing for this, however sweat rates are very much condition specific so it can be difficult to know how much to replace.

The good news is that if you are using a ‘high strength’ electrolyte that you can’t really go wrong. Many athletes tend to focus on sodium, but it is also important to make sure there is potassium, magnesium and calcium. Calcium and magneisum in particular are massively underrated for performance.

Sodium losses are reported up to around 2g per hour in endurance athletes in hot conditions. But this would be rare. Most people average around 1g. Leading manufacturers of electrolyte tablets typically have between 500mg and 1g of sodium per tablet.

So, with a little trial and error to ensure that there are no gut or other issues (some people can be sensitive to sodium in high amounts) this should be an ‘easy’ fix.

Electrolyte supplementation would be dissolved in water, assuming it is not part of sports drink! Recommended supplemental amounts are in the region of 800mg to 1g per litre of water.

This also means that we can use fluid losses to estimate sodium losses, 1 litre of sweat contains on average 800mg of sodium.

It is important to note that electrolytes in our sweat are always a lower concentration than in the blood, this means that we lose fluid faster than we do electrolytes.

This leads nicely into the next section…

Fluid Replacement.

The Problem: Losses of fluid of greater than 2% of bodymass can start to chip away at our performance. Sweat rates are highly individual and dependant on environment.
We are also limited by the rate at which we can take on board, so if sweat rates exceed fluid uptake rates then dehydration is inevitable and potentially very dangerous if out in the heat in for many hours.

The Solution: Firstly, we can calcualte our individual sweat rates to work out how much fluid we are losing. The closer to replicating the environment of competition the more accurately we can generate fluid replacement strategies.

To calculate sweat rates we need to do 4 things:

a) Weigh yourself naked before your training session.

b) Measure exactly how much fluid you consume during your training sessions in litres.

c) Towel off any sweat, and weigh yourself after training.

d) Measure the duration of the session in hours, ideally make this more than an hour.

We then perform the following calculation:

Fluid Loss = (a - b + c)/d

Example, If we had a cyclist who weighed 72kg before training for one hour, 71kg after training and consumed 1 litre of fluid.

Fluid Loss = (72 - 71 + 1)/1

Fluid Loss = 2/1 = 2 Litres per hour!

This gives us a target to hit, but it is important to note that even if we can’t consume this amount per hour, that even if we can get ‘close’ to this we can keep ourselves below a threshold under which performance is not effected by sweat losses.

We can also train our gut to take on board more food and fluid by gradually increasing the amounts we consume during training over time.

As a final ‘unknow’ when we exercise we also produce water as a result of glycogen breakdown and metabolism of fat to produce energy. Therefore we do ‘internally contribute' to our fluid balance through these pathways, but the significance of this is questionable in a sports performance setting.