Cocoa Flavanols and Exercise Capacity

Not Applicable

Completed

• Conditions: Exercise Capacity
• Interventions: Other: Cocoa

• Registration Number: NCT01259739
• Lead Sponsor: Heinrich-Heine University, Duesseldorf

Brief 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)

Detailed 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 Timeline

• Study Start: 2010-11
• Study First Submitted: 2010-12-13
• Study First Submitted QC: 2010-12-13
• Study First Posted: 2010-12-14
• Primary Completion: 2013-10
• Status Verified: 2013-11
• Study Completion: 2013-11
• Last Update Submitted: 2013-11-07
• Last Update Posted: 2013-11-08

Recruitment & Eligibility

• Status: COMPLETED
• Sex: Male
• Target Recruitment: 13

Inclusion Criteria

• highly trained cyclists (VO2 peak > 50 ml/kg bodyweight)
• refrain from cocoa ingestion during trial
• training continued throughout testing
• > 20 years
• male

Exclusion Criteria

• > 36 years
• poor endothelial function
• acute infection
• any chronic heart or pulmonary disease
• arrhythmias
• acute or chronic renal failure
• smokers
• cardio-vascular risk factors : diabetes mellitus, hypertension, hyperlipidemia
• intake of nutrition supplements (l-arginine, creatinine)
• intake of WADA listed doping substances

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Flavanol rich cocoa	Cocoa	(596 mg), dissolved in water, twice daily intervention
flavanol poor cocoa drink	Cocoa	( 13mg) dissolved in water, twice daily intervention

Primary Outcome Measures

Name	Time	Method
Cardiopulmonary exercise capacity (time to complete time trail, lactate anaerobic threshold, cardio-pulmonary exercise capacity	7 days

Secondary Outcome Measures

Name	Time	Method
Endothelial function	7 days

Trial Locations

Locations (1)

Heinrich-Heine-University; 🇩🇪 Duesseldorf, NRW, Germany