Dark Chocolate Supplementation Elevates Resting Energy Expenditure in Exercise Trained Females

Area of Science:

• Nutritional Science
• Exercise Physiology
• Metabolic Health

Background:

• (-)-epicatechin-rich cocoa products show potential health and exercise benefits.
• Dark chocolate (DC) contains (-)-epicatechin, a flavanol with antioxidant properties.

Purpose of the Study:

• To investigate the effects of 30-day dark chocolate supplementation on resting and exercise energy metabolism in athletically fit females.
• To determine if DC supplementation influences resting energy expenditure (REE) and exercise energy expenditure (EEE).

Main Methods:

• Randomized, single-blind study with 18 trained female subjects.
• Supplementation with 20g/day of 70% dark chocolate (DC) or a calorically matched white chocolate (WC) for 30 days.
• Indirect calorimetry assessed REE and EEE (steady-state cycling at 50W and 100W) pre- and post-supplementation.

Main Results:

• Dark chocolate supplementation significantly increased resting energy expenditure (REE) by approximately 9.6% (p=0.017).
• No significant differences were observed in steady-state exercise energy expenditure (EEE) at 50W or 100W between the DC and WC groups.
• Substrate utilization at rest and during exercise remained unchanged in both groups.

Conclusions:

• A small daily dose of dark chocolate can significantly elevate resting energy expenditure in athletically fit females.
• Dark chocolate supplementation does not appear to impact steady-state exercise energy expenditure or substrate utilization in this population.