Cocoa Flavanols and Exercise Capacity

Exercise Capacity Clinical Trial

Official title: The Impact of Dietary Cocoa Flavanols on Cardio-pulmonary Exercise Capacity in Human.

Status Completed

Clinical Trial Summary

The purpose of this study is to characterize the potential improvement of cocoa flavanols on exercise capacity in highly trained cyclist. A placebo-controlled double-blinded randomized control study will be performed in 13 highly trained cyclist (crossover design). Participants will perform a baseline exercise testing on an ergometer. They will receive either a flavanol-poor or flavanol rich cocoa drink twice daily for one week before a second and third exercise testing is performed. The order of drinks is randomized and balanced (high-flavanol-->low-flavanol drink or low-flavanol drink-->high-flavanol drink)

Clinical Trial Description

13 participants (highly-trained cyclist, accustomed to exercise testing on ergometers will be enrolled (VO2max>50 ml/kg, FMD >5%, non-smokers, no medication, no diseases, age 20-36, male).

Baseline Testing:

Participants will perform a baseline testing consisting of an ergometric test with a step-wise increase of workload until exhaustion to determine lactate anaerobic threshold and cardio-pulmonary exercise capacity. Vascular function is monitored by Doppler Ultrasound.

In a second test, participants will perform a time trial (goal: as fast as possible)

Flavanol intervention Participants will twice daily receive either a flavanol-poor cocoa drink (13mg/dl)or a flavanol-rich cocoa drink (596mg/dl) over a period of 7 days. Order is randomized and balanced. Subjects will crossover to the second arm after a washout period of 7 days.

Testing performed on baseline day is repeated after the intake of both drinks

In a subgroup of n=6 participants, we will test whether the blood pressure cuff maneuver used for FMD will itself modify nitrite levels. For this the manuever will be completed 4 times and compared to n=6 untreated controls. in another subgroup 6 participants will receive 4times the maneuver but reperfusion will be limited by means of an ultrasound probe. ;

Study Design

Allocation: Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Crossover Assignment, Masking: Double Blind (Subject, Investigator, Outcomes Assessor), Primary Purpose: Basic Science

Related Conditions & MeSH terms

• Exercise Capacity

• NCT number: NCT01259739
• Study type: Interventional
• Source: Heinrich-Heine University, Duesseldorf
• Status: Completed
• Phase: N/A
• Start date: November 2010
• Completion date: November 2013