Comparison between carbohydrate feedings before and during exercise on running performance during a 30-km treadmill...

Area of Science:

• Exercise Physiology
• Sports Nutrition

Background:

• Optimizing fuel availability is crucial for endurance performance.
• Both pre-exercise meals and intra-exercise carbohydrate intake are common nutritional strategies.

Purpose of the Study:

• To compare the impact of a carbohydrate-electrolyte solution during exercise versus a pre-exercise carbohydrate meal on 30-km running performance.

Main Methods:

• Ten endurance-trained males completed two 30-km treadmill runs under controlled conditions.
• One trial involved a pre-exercise carbohydrate meal (M), the other a carbohydrate-electrolyte solution during exercise (C).
• Physiological markers and performance times were recorded for both trials.

Main Results:

• No significant differences in 30-km running performance times or self-selected speeds were observed between the carbohydrate meal (M) and carbohydrate-electrolyte solution (C) trials.
• Oxygen uptake, heart rate, and perceived exertion were similar across both conditions.
• Blood glucose levels were higher during the initial 20 km in the carbohydrate-electrolyte solution (C) trial, while the carbohydrate meal (M) maintained glucose above 4.5 mmol.L-1 throughout.

Conclusions:

• Both a pre-exercise carbohydrate meal and intra-exercise carbohydrate-electrolyte solution ingestion result in comparable endurance running performance.
• These findings suggest flexibility in nutritional strategies for supporting prolonged exercise in trained individuals.