Hi, I'm Jo Scott-Dalgleish, a sports nutritionist with a focus on energy management and nutrition for endurance sports. I'm working with Whole Earth peanut butter, official supplier to the British Triathlon Federation, to bring nutritional advice for triathletes on a race day.
Race day nutrition can unquestionably help you to perform better. If you want to go faster, you should make nutrition a focus.
Train your breakfast
Have your breakfast no later than two hours before the race. Ideally allow yourself three hours in order to best digest your food to avoid unpleasant consequences.
Race day nutrition is very individual so you should practice eating a few things to find out what works best for you and, on race day, stick to that plan.
A sensible breakfast would be white toast or bagel with honey and small amount of Whole Earth peanut butter. The carbs will help to fuel you during the exertion of the race and a small amount of fat and protein from the peanut butter will enhance that.
During the race
If the race is going to be under an hour, you don't need to take on any food during that time. Only very fast people will finish a sprint triathlon in that time. If you're expecting it to be around an hour and a half, you should look to have one energy drink whilst on your bike. Due to the speed you are going at, sugar will provide the most effective carbs during the race.
Elite athletes can complete the Olympic distance in two hours, but most amateurs will take over two and a half hours. You shouldn't eat solid food during the race, but you could go for an energy gel in addition to an energy drink. Again, the best time to consume this is whilst on your bike.
Water consumption is very personal. There's no single guideline for everyone. It depends on your size and how much you sweat. It can be dangerous to drink too much. The current guidelines are to drink according to your thirst.
You should make sure you go into the race hydrated. I'd suggest drinking half a litre of water or a sports energy drink in the couple of hours before the race. You should drink this slowly and not glug it down too fast.
Again you should practice what to take on board. A sports drink is an easy-to-digest way to top up your carbohydrates. I'd always recommend avoiding carbonated drinks with caffeine in favour of an energy drink made for endurance sports with 6% carbohydrate content and electrolytes, you can find these in cycling stores.
After the race, you should rehydrate fully until your urine is clear.
Recovery is the most important stage, as it'll affect your future training and is important to help avoid fatigue and injuries. You want a two-stage recovery.
After the race, once you've got your breath back, it's important to have a mix of carbohydrates and protein that's easily to digest. Here, I'd recommend a peanut power smoothie made with yoghurt, banana, Whole Earth peanut butter, porridge oats and milk, or non-dairy almond milk. You should have this within half an hour of finishing and this will replenish your muscle glycogen which is the stored carbohydrates that you've just emptied out and the protein will kick-start the process of helping your muscles recover.
A couple of hours later, you should have a proper meal - which might be chicken and rice - or pasta and cheese.
Remember nutrition is personal, it's as important to practice this as it is your swim, bike and run. There are no universal rules. Though Usain Bolt is a special case and 100m is a very different discipline to triathlon, he found what suited him as a pre-race meal and stuck to it. Though I wouldn't recommend chicken nuggets to my clients!
Best of luck with your race!