So your next Ironman or 70.3 is upon you and hopefully you have all tested our nutrition plan in training.
If you are new to longer distances or have had nutrition issues in prior races, here is a simple way of validating the essentials, preferred products aside.
In a basic nutrition plan I focus on the essentials for the distance and push preferences aside for validation. Flavour, minerals, and consistency are preferences, the 1%ers which make things palatable, but don’t effect performance significantly once consumed. For validation, I ignore these.
The essentials are Water, Carbohydrates and Sodium.
Water: plan to consume a minimum of 750 ml to 1000 ml per hour, especially on the bike. That’s 3 biddons on the bike for most of us. Count Sport Drink in this volume.
Carbs: Consume up to 60 grams carbs per hour. Check the labels of your sports drink, Sport bars and gels, adding up per hourly plan. Usually around 3 gels per hour, or 1 litre sports drink. Beware if you add in solids on top of sports drink as you can easily overdo it and cause gastric stress.
Sodium: Plan to consume 500 mg per hour. Again read the labels and do the sums. Less could mean cramp or gastric stress, or at least a significant performance drop. Sports drinks should provide most of this, running on gels or bars alone could leave you short. Salt tablets can cover deficits at 500 to 600 mg per tablet.
Water, Carb and Sodium needs per hour can differ but the above applies to around 95% regardless of size or weight. Exceptional temperature and humidity can also vary the optimal volumes, however the above is a baseline which will work for almost all.
There is value in doing sweat tests and sodium loss tests if you experience symptoms in races, however I always suggest trying the above first. For most the issues are resolved.