Cocoa Flavanols and Exercise Capacity

Study Overview
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Brief Summary
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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
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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.

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

Conditions
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Exercise Capacity

Intervention / Treatment
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* Other: Cocoa


Participation Criteria
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Eligibility Criteria
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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

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 36 Years

Sexes Eligible for Study
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Male

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Flavanol rich cocoa<br>(596 mg), dissolved in water, twice daily intervention | Other: Cocoa<br>* dissolved in water twice-daily intervention<br>|
| Experimental: flavanol poor cocoa drink<br>( 13mg) dissolved in water, twice daily intervention | Other: Cocoa<br>* dissolved in water twice-daily intervention<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cardiopulmonary exercise capacity (time to complete time trail, lactate anaerobic threshold, cardio-pulmonary exercise capacity |  | 7 days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Endothelial function |  | 7 days | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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trained cyclists, no medications, no diseases, non-smokers