Does chewing coca leaves influence physiology at high altitude?

Area of Science:

• Physiology
• Biochemistry
• Pharmacology

Background:

• Coca leaves (Erythroxylon coca) have a long history of use by Andean populations for performance enhancement.
• The physiological and biochemical effects of coca leaf consumption, particularly during exercise, remain a subject of debate.

Purpose of the Study:

• To investigate the biochemical and physiological effects of chewing coca leaves during standardized exercise.
• To analyze changes in key metabolic parameters and physiological markers.

Main Methods:

• Ten healthy adult males at high altitude (2700 m) in Peru participated.
• Subjects chewed 8g of coca leaves before a 20-minute stationary cycling exercise.
• Cutaneous microdialysis was used to monitor biochemical changes; physiological parameters (blood pressure, pulse, oxygen saturation, VO2 max, ECG) were recorded.

Main Results:

• No significant changes in oxygen saturation, blood pressure, or pulse rate were observed.
• Hyperglycemic response noted, with increased levels of glucose, lactate, and pyruvate.
• Glycerol levels also increased, while glutamate remained unchanged, suggesting a blocked glycolytic pathway.

Conclusions:

• Coca leaf consumption appears to inhibit glucose oxidation, leading to substrate accumulation.
• Energy for exercise seems to be primarily derived from fatty acid beta-oxidation.
• Findings suggest coca leaves may offer benefits for prolonged physical activity.