Today, we explore whether a food first approach is better than a supplemental approach to fuelling endurance based exercise.

Carbohydrate (CHO) recommendations during endurance based sports are based on duration and intensity. Of which, the greater the duration or intensity, the greater amount of carbohydrates needed to maintain work capacity.

Current guidelines are as follows:

<60 mins = no need for CHO during, 60-120 mins = 30g CHO/hour, 120-180 mins – 60g CHO/hour, >3 hours = 90g/CHO hour (in some instances, this can be pushed to 120g CHO/hour).

Ultimately, hitting these CHO hourly quotas can be difficult. The main determinants of this are: palatability (flavour fatigue), logistics, or gastrointestinal issues.

Therefore, what’s the best way to fuel exercise during to ensure you meet the body’s demands: Food (bars, fruit etc) or CHO supplements (drinks, gels etc)?

A recent 2022 review by Reynolds et al concluded that both foods and supplements had an equal performance enhancing effect on endurance performance.

However, athletes were at greater risk of gastrointestinal issues when fuelling their sessions with foods vs supplements, particularly when exercise lasted >2 hours.

Gastrointestinal issues during exercise often arise as there’s less blood in the gut to aid with digestion and absorption of foods. This is because a greater amount of blood is directed to the working muscles to support performance (fight or flights vs rest and digest).

Therefore, having harder to digest food will further amplify this issue…especially when time x quantity increases. i.e. <120 mins where you require 30g CHO/hour may be fine as the gastrointestinal load is small, where hitting 90-120g CHO/hour for events lasting >3 hours may be problematic.

Knowing this, the approach I take with athletes who are training and competing >3 hours is to use a combination of the two. This will (1) reduce the likeliness of GI distress, and (2) reduce flavour fatigue….as a by-product, the athlete will consume more CHO and be able to better tolerate it.

Therefore, I would recommend rotating between solid, semi-solid and liquid nutrition to support your fuelling demands. Personal preference is key – assuming you hit the hourly quotas and experience minimal GI distress, the options are endless.