Clinical trial NCT02627547: Impact of Training Status on Bioavailability of Flavanones
Official title: Impact of Training Status of Endurance Athletes on Bioavailability of Flavanones
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Healthy
Keywords: Flavanones
Endurance-trained athletes
Biological availability
Lead sponsor: University of Glasgow
Sponsor class: OTHER
First posted: 2015-12-11
Enrollment: 13
Sex: MALE
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: NA
Intervention model: SINGLE_GROUP
Primary purpose: BASIC_SCIENCE

Brief summary: 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.


Eligibility criteria: 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

Primary outcomes:
measure: • Plasma pharmacokinetics of naringenin, hesperetin, eriodictyol, isorhamnetin and phenolic acid metabolites
timeFrame: 24 hours
measure: • Urinary excretion of naringenin, hesperetin, eriodictyol, isorhamnetin and phenolic acid metabolites
timeFrame: 24 hours
Secondary outcomes:
measure: Maximal Oxygen Consumption
timeFrame: 30 minutes
measure: Body weight
timeFrame: 7 days
measure: Body fatness
timeFrame: 7 days
measure: Dietary Intake
timeFrame: 7 days
Other outcomes:
Locations:
city: Glasgow
country: United Kingdom
facility: University of Glasgow School of Medicine
Study officials:
affiliation: University of Glasgow
name: Dalia Malkova
role: PRINCIPAL_INVESTIGATOR
References:
citation: Pereira-Caro G, Clifford MN, Polyviou T, Ludwig IA, Alfheeaid H, Moreno-Rojas JM, Garcia AL, Malkova D, Crozier A. Plasma pharmacokinetics of (poly)phenol metabolites and catabolites after ingestion of orange juice by endurance trained men. Free Radic Biol Med. 2020 Nov 20;160:784-795. doi: 10.1016/j.freeradbiomed.2020.09.007. Epub 2020 Sep 11.
citation: Pereira-Caro G, Polyviou T, Ludwig IA, Nastase AM, Moreno-Rojas JM, Garcia AL, Malkova D, Crozier A. Bioavailability of orange juice (poly)phenols: the impact of short-term cessation of training by male endurance athletes. Am J Clin Nutr. 2017 Sep;106(3):791-800. doi: 10.3945/ajcn.116.149898. Epub 2017 Jul 26.