Carbohydrate-electrolyte feedings improve 1 h time trial cycling performance

Area of Science:

• Sports Science
• Exercise Physiology
• Nutrition Science

Background:

• Carbohydrate-electrolyte (CE) intake enhances endurance performance for prolonged exercise (>2 hours) at moderate intensities (60-75% VO2max).
• The impact of CE intake on high-intensity exercise (≥80% VO2max) of shorter duration (approx. 1 hour) remains less understood.

Purpose of the Study:

• To investigate the effect of a 7.6% CE solution on time trial cycling performance during approximately one hour of high-intensity exercise.
• To assess the efficacy of CE supplementation in improving performance metrics during a standardized, reproducible cycling test.

Main Methods:

• Nineteen endurance-trained cyclists completed two randomized, counterbalanced time trial cycling tests.
• Participants ingested either a 7.6% CE solution or a placebo (flavored water) totaling 14 ml/kg at the start and during exercise.
• Performance was measured by the time to complete a set amount of work, with workload and intensity monitored.

Main Results:

• Ingestion of the CE solution significantly reduced the time to complete the set work by 2.3% (p < 0.001).
• Average completion time was 58.74 min with CE versus 60.15 min with placebo.
• Exercise intensity was maintained at approximately 76.4% of maximal work rate (Wmax) with CE and 74.8% Wmax with placebo (p < 0.001).

Conclusions:

• Carbohydrate-electrolyte (CE) ingestion improves cycling performance during high-intensity exercise of approximately one-hour duration.
• CE supplementation is effective in enhancing performance even in shorter, intense exercise bouts, not just prolonged endurance events.
• These findings support the use of CE solutions to boost performance in events lasting around one hour at high intensities.