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Q: No matter what I eat, I have GI issues. Should I try an all-liquid race day diet? – Gut Checked
The short answer: Give it a whirl; it might work for you—just make sure it works long before race day. Take a look at Cody Beals, a professional triathlete with multiple 70.3 wins to his name who turned to a race-day liquid diet for the same reason you’re asking about it: to meet fuel and hydration needs without taxing his gut.
How do I transition to an all-liquid nutrition strategy?
If you want to try an all-liquid race day nutrition strategy, start slow. Going for mega-doses of liquid carbohydrate right off the bat is going to result in the exact GI symptoms you’re trying to avoid. That’s why it’s important to train your gut to absorb more carbs, just like you train your legs to handle longer distances in running. To start, aim for 30 grams of carbs (plus some electrolytes) per 20 ounces of fluid, and monitor energy levels and gut tolerance. Dial up the carbohydrate concentration as needed and as the gut allows. (See options below to get started.) For athletes who are particularly prone to GI distress while training or racing, it can help to choose liquids free from protein and fat. as slower digesting macronutrients that may cause issues.
Does an all-liquid nutrition strategy for racing actually work?
Besides better tummy comfort, what can you expect from going all-in on liquid? Possible performance gains, thanks to the fact that fluid empties out of the gut faster than solids, leading to quicker fuel utilization and possibly better tolerance. A study published in the International Journal of Sport Nutrition and Exercise Metabolism found that intake of solid fuel (bars) during intense cycling was more likely to increase gut discomfort and perceived exertion compared to gels or sports drinks. Researchers even found, in this admittedly small study of 12 well-trained cyclists, that solids reduced peak power versus gels. Follow-up studies have had similar findings, with one 2017 study stating that “carbohydrate bar ingestion reduced peak power, gut comfort, and ease of exertion.”
Is it a good idea to use only liquid to fuel during a race?
Just remember, as with any fueling strategy, there can be drawbacks. On days where thirst is not paramount, for instance, athletes need to remind themselves to drink for their sole source of energy. Additionally, if a bottle or two drops from your cages while riding, you could be running on empty until transition, which can result in significant energy deficits and a consequent bonk. Finally, you must take care to not over-concentrate carbs or over-drink electrolyte-devoid beverages as intolerance or hyponatremia can occur, respectively.
Still, athletes in search of a fueling strategy that meets energy needs without bombarding the gut should consider trying the all-liquid approach.
Liquid Fuel Options for Triathlon Training and Racing
Tailwind Endurance Nutrition
A blend of glucose, sucrose, and electrolytes mixes with water to meet energy, hydration, and electrolyte needs. One scoop provides 100 calories with 25 grams of carbs and electrolytes. Mix 2-3 scoops (50-75g of carbs) in 24 ounces of water per hour.
Heed Sports Drink
Each scoop supplies 100 calories and 27 grams of carbs from maltodextrin (carb more complex than sucrose or glucose that is generally well-tolerated), along with balanced electrolytes and ingredients designed to buffer lactic acid and help balance energy levels.
A unique mix from the experts at First Endurance, EFS-Pro contains high levels of electrolytes (1,400mg), 30g of carbs, and 120 calories per serving—as well as BCAAs (branch chain amino acids), which can help fuel the brain (and help you stay tough) when racing or undertaking high-intensity workouts.
Infinit Nutrition Go Far Endurance Fuel
This is an isotonic sports drink that packs a heavy punch in terms of calories per serving, as well as electrolytes and carbs. With close to 300 calories per serving it is ideal for those athletes looking to get their fuel from a liquid-only source—and it’s very palatable and easy to get down, too. With Infinit Nutrition, it’s also possible to dial in your own custom-made nutrition blends.