Impact of Training Status on Bioavailability of Flavanones

Study Overview
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Brief Summary
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Flavonoids are compounds that have been proven to have a beneficial effect on health, such as reducing the risk of developing cardiovascular disease and, in some cases, cancer. Citrus juices have a high flavonoid content. However, the absorption of flavonoids into the body is limited. This study will investigate whether being physically active improves the absorption of flavonoids. Endurance trained athletes will be invited to participate. Following screening procedures (a. Health Screening Questionnaire; b. height and weight measurement for calculation of Body Mass Index; c. maximal oxygen consumption (VO2max) uptake test, eligible participants will undertake two experimental tests; one during a period of normal training, the other immediately following 1 week of detraining. In the morning of the experimental trial participants will consume 500 mL of orange juice. Blood samples and urinary fractions will be collected prior (base line) to and for 24 hours after orange juice consumption. Participants will be asked to follow a special polyphenol-free diet and record weighed dietary intake for 2 days preceding each trial and during the day of the experimental trial. The study aims to: Determine the effects of training status of endurance athletes on bioavailability of flavanones in endurance trained individuals Determine whether changes in bioavailability of flavanones are related to changes in biomarkers of inflammation, oxidative stress, plasma lipids and insulin sensitivity.

Official Title
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Impact of Training Status of Endurance Athletes on Bioavailability of Flavanones

Conditions
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Healthy

Intervention / Treatment
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* Behavioral: Normal training
* Behavioral: De-training


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: trained regularly for at least 4 years and typically perform at least 5 hours of endurance training per week (distance runners, triathletes, cyclists) healthy normotensive non-smokers not taking any drug therapies VO2 max >50 ml/kg body mass Exclusion Criteria: history of gastrointestinal disease vegetarian unstable food habits VO2 max < 50 ml/kg body mass

Ages Eligible for Study
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Minimum Age: 18 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
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Experimental tests<br>2 sets of experimental tests; once, during a period of normal training and repeated following one week of de-training | Behavioral: Normal training<br>* 5-10 hours of endurance training each week<br>Behavioral: De-training<br>* No training<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| • Plasma pharmacokinetics of naringenin, hesperetin, eriodictyol, isorhamnetin and phenolic acid metabolites | Change in plasma concentrations collected at base line (0 hours) and 0.5,1, 2, 3,4,5,6,7,8, and 24 hours after ingestion of orange juice | 24 hours | 
| • Urinary excretion of naringenin, hesperetin, eriodictyol, isorhamnetin and phenolic acid metabolites | Change in concentrations in urinary fraction collected at base line (0 hours) and after ingestion of orange juice (0-5, 5-8, 8-10, 10-24 hours) | 24 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Maximal Oxygen Consumption | Maximal Oxygen Consumption (ml/kg/min) measured in trained state by Douglas bag method | 30 minutes | 
| Body weight | Difference in body weight in kilograms between trained and detrained states measured by TANITA scales (TBF-300, Cranlea, UK) | 7 days | 
| Body fatness | Difference in percentage of body fat between trained and detrained states measured by bioelectrical impedance method (TBF-300, TANITA, Cranlea, UK) | 7 days | 
| Dietary Intake | Difference in energy/macronutrient intake between trained and detrained states measured from 7 day weighted food records | 7 days | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Flavanones, Endurance-trained athletes, Biological availability