Ironman Nutrition

Race Day Nutrition

You have more that likely see wildly different guidelines for the amount of calories needed on race day. Remember that predictions can vary a great deal from athlete to athlete. Some athletes can consume up to 600 calories per hour easily while others struggle at 225 per hour.

The key is to practice what your body can handle during training and C priority races. Once you are happy your nutrition and hydration strategy should be practiced under race type conditions in the months leading up to you’re A race. Do not try anything new on race day. The aim is to make race day as normal as possible for your body.

10min to Start: Drink 300-500ml of sports drink (not too strong), or 1 gel with ½ a bottle of water. This is the last thing you will consume until your heart rate has dropped to below your early race target on the bike.
On the Bike: Drink ½ a bottle of water before eating anything else. This will settle the stomach and allow easier absorption of food according to Friel and Byrn (2009).  Once Heart rate and stomach have settled, begin consuming gels, sports bars and sports drinks as required.

Suggested Strategy:
0-20min: Water only
20-40min: 150 Calories
40-60min: 150 Calories
60-120min: 150 Calories per 20 min

This would give 750 calories in the first 2 hours and is a suggested starting point for male athletes. The reason for the increased amount in the first 2 hours of the bike is that appetites and concentration can fade during the day and it’s a good idea to have a few extra calories in the bank.

A target for most men according to Friel and Byrn (2009) would be 450 calories per hour and 200-300 calories for women. This will be very dependant on size and time on the course.  Targeting 450 calories will mean you might end up with around 400. Remember to always base your intake on what you have learned in training and other races.  Finally make sure you eat right up to the end of the bike as anything might happen on the run and again its good to have something in the bank.

T2: Take 1-2 gels if you can keep them down followed by water.
RUN: A good idea is to alternate between cola/water and sports drink/water at every aid station. It is advisable to start on cola straight away. If you are peeing a lot drop the water but keep the cola and sports drink. A lot of athletes might not eat anything during the run, which should be fine as long as you keep up the sports drink/cola.

Drink only water until your heart rate settles, then drink 1 to 2 bottles per hour of water alternating with sports drink.  If you are peeing more than once per hour stick with sports drink.  If you’re not peeing at all slow down and increase hydration. Make sure you finish the bike well hydrated to avoid walking later.

Target 1 liter per hour of water and ease off if you start peeing more than once per hour.  If you’re eating gels, bars and liquid carbs. On the bike, a high water intake is vital in the early part of the cycle due to the concentrated nature of your food.  Friel and Byrn (2009) suggest that if you are bloated on the run and peeing go for sports drinks and cola only. If you are bloated and not peeing, take an electrolyte tablet, slow down and switch to water only.

Most athletes probably don’t need it. If you think you might you need to experiment during your long sessions in training.  Make sure the sports drink that you are using contains some sodium, as racing long without any could be risky.  As a start point 400mg of sodium per hour is enough for most athletes.  Make sure to read the labels of your sports drinks to calculate how much sodium you are consuming weeks before race day.

Coach Jenks Ironman nutrition tips

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