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CompletedNCT01557738Updated Jun 25, 2014

Role of Flavanols in Exercise and Aging

An interventional study of High Flavanol Trial and Low Flavanol Trial in Aging, sponsored by University of Texas at Austin. Completed at 1 site in United States. Open to participants aged 18 Years to 80 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2014-06-25.

Sponsored by University of Texas at Austin · Not applicable, Interventional, and Basic science

Phase
Not applicable
Study type
Interventional
Enrollment
20
Allocation
Randomized
Ages
18 Years to 80 Years
Sex
All
01

Study summary

It has well known that diets rich in fruits, vegetables and cocoa products are associated with positive health benefits and these positive effects have been shown to be due to compounds they contain called flavanols. Flavanols have been shown to exert their positive effects by indirectly increasing nitric oxide (NO) bioavailability. NO is a potent vasodilator that is believed to play a role in increasing blood flow to active muscle during exercise. This regulatory process is impaired with healthy aging. The underlying premise to this study is that if NO bioavailability can be increased following flavanol ingestion, will there be a restoration of blood flow during exercise in older individuals? Accordingly, the first part of this research project will compare the acute vascular effects of flavanol ingestion between a young and old group. The investigators have hypothesized that both groups will show an improvement in blood flow to active muscle during exercise, though the magnitude of the change will be greater in the older group. The second part of this project will look at the effects of 4 weeks of daily flavanol ingestion in the old group. The investigators hypothesize that subjects will demonstrate an improvement in blood flow to active muscle during exercise after the 4 week intervention and that the magnitude of the change will be greater than the acute effects. Findings from this proposal will provide evidence for the efficacy of flavanols to be used (as a simple and safe lifestyle intervention) to reverse or combat impaired blood flow regulation in older individuals.

02

Conditions studied

  • Aging

Keywords

  • Exercise
  • Blood Flow
  • Nitric Oxide
  • Aging
  • Antioxidant
  • Flavanol
  • Young (18-30 yrs)
  • Aging (60 - 80 yrs)
03

In context

Lead sponsor

University of Texas at Austin is the lead sponsor of 319 studies on the registry; 78 are open to participants now.

Of its 10 completed or terminated interventional studies of FDA-regulated products, 5 (50%) have results posted.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years to 80 Years
Sexes eligible
All
Accepts healthy volunteers
Yes

Inclusion criteria

  • Males and Females between 18 - 30 years old
  • Males and Females between 60 - 80 years old

Exclusion criteria

Exclusion Criteria:

  • cardiovascular and/or microvascular disease
  • blood clotting disorder
  • pregnant lady
  • current smoker (or regularly smoked within last year)
  • a history of an adverse reaction to cold
  • taking medications known to effect the autonomic nervous system
05

Study design

Phase
Not applicable
Primary purpose
Basic science
Allocation
Randomized
Intervention model
Crossover assignment
Masking
Double (Participant, Investigator)
Enrollment
20 participants (actual)

Study arms

  • Experimental
    Acute effects of flavanol consumption

    The outcome measurements will be made on all study participants before and 2 hours after consumption of the high flavanol beverage.

    Dietary Supplement: High Flavanol Trial

  • Placebo comparator
    Low Flavanol Trial; acute effects

    Once again, the outcome measurements will be made on all study participants before and 2 hours after consumption of the low flavanol beverage.

    Dietary Supplement: Low Flavanol Trial

  • Experimental
    Long-term effects of flavanol consumption

    Only those study participants over 60 years of age will continue with this arm of the trial. The same outcome measures will be performed following 4 weeks of daily consumption of a high flavanol beverage.

    Dietary Supplement: High Flavanol Trial; long-term

  • Placebo comparator
    Low Flavanol Trial; long-term effects

    Only those study participants over 60 years of age will continue with this arm of the trial. The same outcome measures will be performed following 4 weeks of daily consumption of a low flavanol beverage.

    Dietary Supplement: Low Flavanol Trial; long-term effects

Interventions

  • Dietary supplementHigh Flavanol Trial

    The experimental trial (high flavanol content) will involve the consumption of a beverage containing about 1000mg of cocoa flavanols.

  • Dietary supplementLow Flavanol Trial

    The placebo trial (low flavanol content) will involve the consumption of a beverage containing 75 mg of cocoa flavanols.

  • Dietary supplementHigh Flavanol Trial; long-term

    The experimental trial (high flavanol content) will involve the daily consumption of a beverage containing about 1000mg of cocoa flavanols for 4 weeks. Subjects will be provided with 28 packets of the beverage to take home with them.

  • Dietary supplementLow Flavanol Trial; long-term effects

    The placebo trial (low flavanol content) will involve the daily consumption of a beverage containing 75 mg of cocoa flavanols for 4 weeks. Subjects will be provided with 28 packets to take home with them.

06

What researchers measure

Primary outcomes

  1. Change in femoral blood flow during exercise following flavanol consumption

    Blood flow regulation to active muscles during knee extension exercise can be assessed by using ultrasound to measure blood flow in the femoral artery. This will be done before and after stimulation of the sympathetic nervous system. A baseline value will be obtained and then the measurement will be performed again 2 hours after flavanol ingestion.

    Time frame: During knee extension exercise, change from baseline in blood flow 2 hours post flavanol ingestion

Secondary outcomes

  1. Change in flow-mediated dilation (FMD) following flavanol consumption

    Flow-mediated dilation is commonly used as an index of nitric oxide bioavailability. Nitric oxide is believed to play a role in blood flow regulation during exercise. A baseline value will be obtained and then the measurement will be performed again 2 hours after flavanol ingestion.

    Time frame: Change from baseline in FMD 2 hours post flavanol ingestion

07

Study locations

1 site
  • University of Texas at Austin: Environmental and Autonomic Physiology Laboratory
    Austin, Texas 78712, United States
08

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Jun 25, 2014, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
09

Registry details

Key details

Study ID
NCT01557738
Lead sponsor
University of Texas at Austin
Responsible party
Robert M. Brothers (Assistant Professor, University of Texas at Austin) — Principal investigator
First posted
Mar 19, 2012
Start date
Dec 2012
Primary completion
Apr 2014
Completion
Apr 2014
Last update
Jun 25, 2014

Study contacts

Michelle Harrison, M.A.
principal investigator · University of Texas at Austin

Oversight

Data monitoring committee
No
View the source record on ClinicalTrials.gov ↗

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