Cocoa Flavanols and Exercise Capacity

Sponsor

Heinrich-Heine University, Duesseldorf (Other)

Overall Status

Completed

CT.gov ID

NCT01259739

Collaborator

(none)

Enrollment

Location

Arms

Duration (Months)

0.4

Patients Per Site Per Month

Study Details

Study Description

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)

Condition or Disease	Intervention/Treatment	Phase
Exercise Capacity	Other: Cocoa	N/A

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 Design

Study Type:

Interventional

Actual Enrollment :

13 participants

Allocation:

Randomized

Intervention Model:

Crossover Assignment

Masking:

Triple (Participant, Investigator, Outcomes Assessor)

Primary Purpose:

Basic Science

Official Title:

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

Study Start Date :

Nov 1, 2010

Actual Primary Completion Date :

Oct 1, 2013

Actual Study Completion Date :

Nov 1, 2013

Arms and Interventions

Arm	Intervention/Treatment
Experimental: Flavanol rich cocoa (596 mg), dissolved in water, twice daily intervention	Other: Cocoa dissolved in water twice-daily intervention
Experimental: flavanol poor cocoa drink ( 13mg) dissolved in water, twice daily intervention	Other: Cocoa dissolved in water twice-daily intervention

Arm

Intervention/Treatment

Experimental: Flavanol rich cocoa

(596 mg), dissolved in water, twice daily intervention

Other: Cocoa

dissolved in water twice-daily intervention

Experimental: flavanol poor cocoa drink

( 13mg) dissolved in water, twice daily intervention

Other: Cocoa

dissolved in water twice-daily intervention

Outcome Measures

Primary Outcome Measures

Cardiopulmonary exercise capacity (time to complete time trail, lactate anaerobic threshold, cardio-pulmonary exercise capacity [7 days]

Secondary Outcome Measures

Endothelial function [7 days]

Eligibility Criteria

Criteria

Ages Eligible for Study:

20 Years to 36 Years

Sexes Eligible for Study:

Male

Accepts Healthy Volunteers:

Yes

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

Contacts and Locations

Locations

	Site	City	State	Country	Postal Code
1	Heinrich-Heine-University	Duesseldorf	NRW	Germany	40225

Sponsors and Collaborators

Heinrich-Heine University, Duesseldorf

Investigators

Principal Investigator: Tienush Rassaf, MD, PhD, Heinrich Heine University Düsseldorf, NRW, Germany
Study Chair: Malte Kelm, MD, PhD, Heinrich Heine University Düsseldorf, NRW, Germany