What if our gut could also be trained for the heat?

When the weather is hot, we immediately think about our body temperature, sweating, or hydration. Much less often about our gut. And yet, during prolonged exercise in the heat, our body has to make choices: more blood is directed towards the working muscles and towards the skin to dissipate heat. The gut can then become one of the areas that pays the price. Blood flow to the gastrointestinal system decreases, the intestinal barrier becomes more vulnerable, and properly absorbing what we drink and eat can become more difficult. This is where a concept originating from elite sport becomes particularly interesting: “Training the Gut.” Research by my colleague and friend Asker Jeukendrup has notably shown that our digestive system is not a passive organ. It is adaptable. By repeatedly practising during training the nutritional strategies we intend to use under challenging conditions, the gut can learn to better tolerate and absorb what we consume. In other words, preparing for the heat should perhaps not stop at heat acclimation, cooling strategies, or hydration. It can also involve what we eat… and our gut. We train our muscles for exercise. We acclimate our bodies to the heat. So why not train our gut as well?