Skip to main content
OpenTrials
Completed

NCT Number: NCT02627547

Impact of Training Status on Bioavailability of Flavanones

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:

1. Determine the effects of training status of endurance athletes on bioavailability of flavanones in endurance trained individuals 2. Determine whether changes in bioavailability of flavanones are related to changes in biomarkers of inflammation, oxidative stress, plasma lipids and insulin sensitivity.

Completed

Looking for future studies?

Notify Me

Key information

Conditions

Healthy

Age range

18 year and older

Sex eligibility

Male

Study type

Interventional

Phase

Not applicable

Primary location

University of Glasgow School of Medicine

Glasgow, United Kingdom

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

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

Treatment and study plan

Normal Training

Behavioral

5-10 hours of endurance training each week

De-training

Behavioral

No training

Primary outcomes

  1. • Plasma pharmacokinetics of naringenin, hesperetin, eriodictyol, isorhamnetin and phenolic acid metabolites

    Time frame: 24 hours

    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

  2. • Urinary excretion of naringenin, hesperetin, eriodictyol, isorhamnetin and phenolic acid metabolites

    Time frame: 24 hours

    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)

Secondary outcomes

  1. Maximal Oxygen Consumption

    Time frame: 30 minutes

    Maximal Oxygen Consumption (ml/kg/min) measured in trained state by Douglas bag method

  2. Body weight

    Time frame: 7 days

    Difference in body weight in kilograms between trained and detrained states measured by TANITA scales (TBF-300, Cranlea, UK)

  3. Body fatness

    Time frame: 7 days

    Difference in percentage of body fat between trained and detrained states measured by bioelectrical impedance method (TBF-300, TANITA, Cranlea, UK)

  4. Dietary Intake

    Time frame: 7 days

    Difference in energy/macronutrient intake between trained and detrained states measured from 7 day weighted food records

Sponsors and collaborators

Lead sponsor

University of Glasgow

Other

Registry information

Official study title

Impact of Training Status of Endurance Athletes on Bioavailability of Flavanones

Important dates

Study start
2013
Primary completion
2015
Study completion
2015
First posted
Dec 11, 2015
Registry last updated
Dec 11, 2015

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Related clinical trials

Published trials that share one or more normalized conditions with this study.