Research

Hormonal

Targeted nutritional training (specifically high-carbohydrate or high-volume intake) adapts the gastrointestinal tract by upregulating SGLT1 transporters and accelerating gastric emptying, thereby increasing exogenous carbohydrate oxidation and reducing GI distress during endurance exercise.

Train your gut like you train your legs. If you plan to consume 60-90g of carbs per hour during races, practice this exact intake during long training sessions. Start with lower amounts and gradually increase over 2-3 weeks to upregulate your SGLT1 transporters. This reduces bloating and diarrhea risk while maximizing energy delivery. Do not restrict carbs on training days if you are an endurance athlete.

GoodSupportsHIGH confidence
It is clear that ‘‘nutritional training’’ can improve gastric emptying and absorption and likely reduce the chances and/or severity of GI problems, thereby improving endurance performance as well as providing a better experience for the athlete.
Asker E. Jeukendrup · Sports Medicine · 2017

Why this rating

Strong animal data and some human studies (Cox et al., Lambert et al.), but the author notes a lack of dedicated human reviews and calls for more studies.

Source

Training the Gut for Athletes

Asker E. Jeukendrup · Sports Medicine · 2017

DOI 10.1007/s40279-017-0690-6

narrative_reviewCited 194×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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