Nutrition Plan + Hydration Plan: 5k, 10k, Standard Duathlon, Sprint Triathlon

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I think a lot of nonsense is written about nutrition and hydration in races.

You are reading this because you are not an elite athlete and, like me, you are not performing at those levels. Nutrition and hydration is obviously important but not to the same degree as for elite athletes who are trying to eek out tiny performance improvements which, to them, does make a difference.

I argue that us mere mortal athletes need to get our nutrition and hydration BROADLY right and avoid making stupid mistakes which WILL ruin your race ie proper nutrition and hydration might give you a slight incremental boost but when done wrong can result in a several percentage point performance below what you should have achieved.

Pre-Race Hydration

How Much Water? Days and weeks before a race you need to be hydrated. Your wee needs to be almost clear most of the time. That’s how you know how much to drink. It could be 2 litres a day (and *that includes* the water in the stuff you eat) or it could be more – but I don’t think so. In terms of the actual amount of cold water you need to drink per day it will be probably about 1.5 litres (3 pints). *BUT* Add to this the amount you need to replace what you lose in sweat – which could EASILY be 1 litre/hour.

Take Water How Often? If you pour a pint of water onto a potted plant it goes straight through. You’re similar. If you drink 3x or 4x of 0.5 litre (1 pint) of water then much of it will ‘go straight through’. That’s what I do wrong. So it’s best you can drink little and often. And I try to do that!!

The Extremes If you drink 3+ litres of cold water a day you might start to leach salts from your body. You don’t want to do that. If you only have a pint of water (0.5litre) the day before a race (when  you should have more) then it will probably make little difference. Obviously if you are running a marathon what I am saying here does not apply!

On the Day Hydration During the race you don’t need any water, unless it is very very hot. 5k – you don’t need it during the race; neither do you need it for 10k; neither do you need it for a Sprint Duathlon/triathlon. A standard/olympic distance Duathlon/Triathlon then you need a bit on the bike leg. A 330ml Lucozade Sport (or other Isotonic) Drink should do it and (see later) also cover your carbs. Immediately before the race again you don’t really need anything except for the Standard Distance Duathlon and maybe the Sprint. A 330ml lucozade sport should sort you out on that front. 

During the Race Consumption Pattern So on the bike leg of your triathlon/duathlon all you need to drink is the Isotonic drink. As before it needs to be sipped. The 40km cycle will take you the best part of an hour. So consume that drink in sips evenly over the first 40 minutes of the ride. Because you are consuming repetitively on the bike then I use one of those aero bottles with a straw as I can keep in an aero position and take sips. Nothing else is needed. 

After the race Get hydrated. Sip up to a litre over an hour starting with some milk or something like ‘For Goodness Shakes’ or whatever they are called.

Anything else? If you get cramp during the race you could be having too much or too little water. (Or it could be a different cause – also including nutrition or lack of appropriate practice). Or more probably it’s something else.

Pre-Race Nutrition

Broadly you want to be all carbed up for the duathlon/triathlon. For the 5k and 10k races it won’t make much difference. All you need is a balanced diet. Additionally you want to avoid stuff that will not have digested before the race. So bacon and pulses the night before a race is not good. A mass of pasta the night before is not good but a bit won’t hurt.

On the Day Nutrition For breakfast you don’t really need anything for the 5k and 10k and sprint duathlon/triathlon just enough to avoid you being sick or feeling unwell if you suffer from that sort of thing during a race. For the  Standard/olympic Duathlon/triathlon it is a bit more complicated. I would recommend getting used to eating something light late as night as your breakfast (elite athletes wake up for a 2AM breakfast). Make sure it’s light. The idea is to replace the carbs your body uses when you sleep so you ‘wake up, topped up’. BUT it has to be light enough that you are able to empty your intestines. You also need to have a nutrition-related routine whereby you always go for number two’s in the morning. And/or make this happen with a coffee (caffeine). This works for me. You don’t want stuff in your body that your body is umming and ahing about digesting when it should be focussed on racing.

Immediately Before The Race Certainly for the duathlon/triathlon I would replenish my carbs with a lucozade sport (look at the new ELITE Lucozade, it is superior), right before the gun. For the 5k and 10k it doesn’t matter. For the sprint duathlon/triathlon, I would probably go for this instead of having anything during the race. 

During the Race Carbs take 30 minutes or so to ‘work’. You have enough carbs for between 90 and 120 minutes in your body at the start of the race. So almost certainly enough for a standard/olympic duathlon/triathlon; but maybe not in some cases!! So combine and hydration and nutritional needs with one isotonic drink sipped during the bike leg; look at gels that don’t require dilution as an alternative eg High5.

Post Race Nutrition Immediately afterwards you need some protein and some carbs (and water of course). Not that much. I have a glass of milk. If you have vegetable protein you might find that all the complex protein constituents are not there. Milk is an animal protein. Add a banana…sorted.

Apparently if you lose more than 2% of your bodyweight in sweat it is a problem. 2% of my body weight is 1.4l (equiv to 1.4kg). I recently measured that I lost 1litre or 1kg over 30 minutes of flat out pace over intervals on a turbo. Probably in real-world-race-reality that would be over 60 minutes. So I probably get to the 2% mark after about 100 race minutes ie I definitely need to hydrate during a standard/olympic duathlon/triathlon race only.

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