Impact of Cocoa Flavanols on Pulmonary Oxygen Uptake Kinetics and Exercise Tolerance in Sedentary Middle-aged Adults

Investigating the Impact of Cocoa Flavanol Supplementation on Pulmonary Oxygen Uptake Kinetics and Exercise Tolerance in Sedentary Middle-aged Adults

In recent years, there has been significant interest in dietary flavonoids (biologically active plant-derived compounds) as potential therapeutics. This is due to the capacity of flavonoids to enhance processes related to energy metabolism and cardiovascular health. We are interested in implementing a short-term supplementation regime (daily cocoa-flavanoid ingestion), in order to explore the possible beneficial effects of flavonoid-based interventions on responses to exercise. Hence, the objective of our study is to examine the impact of short term cocoa-flavanoid supplementation on processes related to energy use (oxygen utilisation). Our aim is to develop a novel intervention which improves cardiovascular health and enhances exercise tolerance.

Study Overview

• Status: Completed
• Conditions: Aging; Sedentary Behavior
• Intervention / Treatment: Dietary supplement: Placebo supplement; Dietary supplement: Cocoa flavanols

• Study Type: Interventional
• Enrollment (Actual): 18
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United Kingdom
  • Liverpool, United Kingdom
    • Research Institute for Sport & Exercise Sciences

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 35 years to 55 years (ADULT)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Aged 35-55 years
• Healthy (no known cardiovascular or metabolic disorders e.g. diabetes)
• Do not engage in regular structured physical training (i.e. less than two sessions for 60 minutes per week, for at least 1 year

Exclusion Criteria:

• Smokers
• Medical history of cardiovascular and/or metabolic disease, including diabetes and abnormal blood pressure
• Family history of cardiovascular disease
• Currently taking any medication
• Asthmatic
• Currently suffering from musculoskeletal injury
• Younger than 35 or older than 55 years old
• Known food allergies or special dietary requirements
• Currently taking any dietary supplements
• Currently engaging in >2 hours structured training per week

Study Plan

How is the study designed?

Design Details

• Primary Purpose: OTHER
• Allocation: RANDOMIZED
• Interventional Model: CROSSOVER
• Masking: TRIPLE

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
PLACEBO_COMPARATOR: Placebo; Placebo supplement, each capsule containing: 0mg total flavanols, matched for caffeine and theobromine content as experimental supplement (2.9 mg caffeine and 22.5 mg theobromine) and microcrystalline cellulose volume filler. Participants consume 4x capsules daily (2AM & 2PM after mixed meal for 7 days.	Dietary supplement: Placebo supplement; Microcrystalline filler, containing 0mg total flavanols.
EXPERIMENTAL: Cocoa Flavanols; Experimental supplement, each capsule containing: 316 mg CocoActiv (Naturex, Netherlands: 100mg total cocoa flavanols, 2.9 mg caffeine and 22.5 mg theobromine) and microcrystalline cellulose volume filler. Participants consume 4x capsules daily (2AM & 2PM) for 7 days.	Dietary supplement: Cocoa flavanols; Flavonoid-rich cocoa powder, containing 100mg total flavanols per 316mg.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Oxygen uptake kinetics	Oxygen uptake kinetics (including time constant, time delay and amplitude of the fundamental oxygen uptake response) will be determined by modelling oxygen uptake during exercise using a mono exponential function. The oxygen uptake data is measured on a breath-by-breath basis during exercise (on a cycle ergometer) using a gas analysis system and face mask. Oxygen kinetics will be measured during three moderate-intensity step exercise tests (at 80% of the gas exchange threshold) and during one severe-intensity (60%∆) step exercise test that is completed to failure.	Over 3 week period (After 7 days of each intervention). Oxygen uptake measured for 9 minutes continuously during exercise bouts (3 min warm up period and 6 minutes of exercise transition)
Exercise tolerance	Participants capacity to exercise to the limit of tolerance, measured to the nearest second. Participants are instructed to exercise at a severe-intensity exercise load (representative of 60% ∆), on a cycle ergometer until volitional exhaustion.	Over 3 week period (After 7 days of each intervention).

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Heart rate	Heart rate will be measured during moderate and severe-intensity exercise bouts, by short-range telemetry.	Over 3 week period (After 7 days of each intervention). Measured during the length of each exercise transition (9 minutes for each moderate intensity bout).
Blood pressure	Systolic and diastolic blood pressure will be assessed following 10 min of seated rest using an automated sphygmomanometer	Over 3 week period (After 7 days of each intervention). Measured over 5 minutes before any exercise testing.
Blood lactate	A finger prick blood sample will be taken to measure blood lactate pre- and post-exercise of each transition using a hand-held automated blood lactate analyser	Over 3 week period (After 7 days of each intervention). Measured immediately before and after exercise
Physical activity and sedentary behaviour	Physical activity levels will be assessed in the 6 days prior to visiting the laboratory by an accelerometer, worn on the hip during waking hours.	Over 3 week period (In the 6 days preceding experimental testing)
Perceived workload	Perceived mental workload will be measured pre and post exercise using NASA Task Load Index and BORG rating of perceived exertion scale.	Over 3 week period (After 7 days of each intervention). Measured immediately before and after exercise

Collaborators and Investigators

• Sponsor: Liverpool John Moores University

Publications and helpful links

General Publications

• Sadler DG, Draijer R, Stewart CE, Jones H, Marwood S, Thijssen DHJ. Cocoa-flavanols enhance moderate-intensity pulmonary [Formula: see text] kinetics but not exercise tolerance in sedentary middle-aged adults. Eur J Appl Physiol. 2021 Aug;121(8):2285-2294. doi: 10.1007/s00421-021-04682-9. Epub 2021 May 10.

Study record dates

Study Major Dates

• Study Start (ACTUAL): April 1, 2018
• Primary Completion (ACTUAL): June 7, 2019
• Study Completion (ACTUAL): June 7, 2019

Study Registration Dates

• First Submitted: April 23, 2020
• First Submitted That Met QC Criteria: April 29, 2020
• First Posted (ACTUAL): April 30, 2020

Study Record Updates

• Last Update Posted (ACTUAL): April 30, 2020
• Last Update Submitted That Met QC Criteria: April 29, 2020
• Last Verified: April 1, 2020

More Information

Terms related to this study

• Other Study ID Numbers: 18/SPS/014

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No