There is not one-size-fits-all when it comes to fuelling your body with fluid or food during an endurance event. Many factors can help determine what to do. It depends on the duration, type of event, access to fuel and how well trained you are.
Research shows consuming approximately 30 grams of carbohydrates every 40-60 minutes when the activity lasts longer than 60 minutes can help improve performance. If you can tolerate more, up to 90 grams of carbohydrates is recommended to see the best results, but it depends on the individual.
The duration of an event plays a significant role in the fuel you choose to use. For endurance events shorter than 60 minutes, if you are have been training regularly you may not require fluid or food.
The use of sports drinks to hydrate and offer a small amount of glucose can be beneficial. For events lasting longer than 90 minutes, such as a half or full marathons and triathlons, topping up your carbohydrate supply will improve your performance.
It is wise to trial your chosen carbohydrate source. Most endurance events provide sports drinks and water for rehydrating and carbohydrate intake at the same time. They are generally well tolerated by everyone. Gels can be easily carried in clothing and provide approximately 20-30 grams of carbohydrates per sachet, but not everyone can stomach these.
For ultra endurance events like Ironman or ultra marathons lasting longer than four hours, body is going to require carbohydrates, protein and some fat.
For these events the difficultly of carrying all the food you require adds an extra element to your planning. Multi-day events such as professional cycling tours require a well-planned recovery strategy between each day.
In short, practice your refuelling strategy before your event. For anything longer than 60 minutes, carbohydrates during the event can certainly contribute to enhanced performance and feeling better overall. For events longer than 4 hours, speak with an Accredited Sports Dietitian for more individualised advice.