Enhancing Elite Mountain Marathon Performance: The Critical Impact of High Carbohydrate Intake

Enhancing Elite Mountain Marathon Performance: The Critical Impact of High Carbohydrate Intake

In the rigorous domain of mountain marathons, where athletes push their limits, nutrition plays a pivotal role. The landmark study by Aitor Viribay and team, as detailed in "Nutrients" (2020), offers profound insights into the effects of high carbohydrate (CHO) intake on exercise-induced muscle damage (EIMD) and internal exercise load in elite runners.

Study Overview

This study's central question was whether increasing CHO intake beyond standard guidelines would mitigate muscle damage and reduce fatigue in a high-stress endurance setting. Researchers divided elite male runners into three groups based on CHO intake levels: 120 g/h (experimental), 90 g/h (control), and 60 g/h (low).

Methodology in Detail

Participants competed in a demanding mountain marathon with a significant cumulative slope. The study meticulously recorded various biomarkers indicative of muscle damage both before and after the race. These included creatine kinase (CK), lactate dehydrogenase (LDH), and glutamic oxaloacetic transaminase (GOT).

In-Depth Results Analysis

Muscle Damage Biomarkers

  1. Creatine Kinase (CK): Post-race, the high CHO intake group showed significantly lower CK levels compared to the control and low groups. This indicates that the higher CHO intake was effective in reducing muscle damage.
  2. Lactate Dehydrogenase (LDH): Similar to CK, LDH levels were substantially lower in the high CHO group, suggesting less damage to muscle tissue.
  3. Glutamic Oxaloacetic Transaminase (GOT): GOT levels, another indicator of muscle damage, were also significantly lower in the high CHO group.

Exercise Load and Perceived Exertion

The study found that the high CHO intake group experienced a notably lower internal exercise load. This suggests that consuming more CHO might lead to a decrease in perceived exertion and overall stress during the race, potentially enhancing endurance and performance.

Expanded Discussion on Findings

The results clearly indicate that a CHO intake of 120 g/h can significantly mitigate markers of muscle damage in the context of a mountain marathon. This finding challenges the established norm of 60-90 g/h, pointing towards the potential benefits of higher CHO consumption for elite endurance athletes.

Implications for Training and Performance

These findings suggest that athletes and coaches might need to rethink nutritional strategies, especially for long-duration endurance events. Training the gut to handle higher CHO loads could be a crucial aspect of preparation for such events, potentially leading to improved performance and faster recovery.

Future Research Opportunities

While this study opens new avenues in sports nutrition, it also raises questions for further investigation. Future research might explore the upper limits of CHO intake and its impact on different types of endurance events, considering variables like individual tolerance and digestive capacity.


Viribay et al.'s study marks a turning point in our understanding of sports nutrition, particularly in the context of endurance sports. It underscores the significance of CHO intake in managing exercise-induced muscle damage and internal exercise load, offering a new perspective on nutritional strategies for elite athletes. This study not only contributes to the field of sports science but also serves as a practical guide for athletes striving to optimize performance in endurance events.

Read the full research article by clicking here.


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