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Study Title and Description

The effects of EGCG on fat oxidation and endurance performance in male cyclists.



Key Questions Addressed
1 For [population], is caffeine intake above [exposure dose], compared to intakes [exposure dose] or less, associated with adverse effects on cardiovascular outcomes?
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Primary Publication Information
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TitleData
Title The effects of EGCG on fat oxidation and endurance performance in male cyclists.
Author S Dean,A Braakhuis,C Paton,
Country
Year 2009
Numbers

Secondary Publication Information
There are currently no secondary publications defined for this study.


Extraction Form: Cardiovascular Design
Design Details
Question... Follow Up Answer Follow-up Answer
What outcome is being evaluated in this paper? Cardiovascular
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What is the objective of the study (as reported by the authors)? This research was undertaken to compare the effects of EGCG with those of caffeine and placebo on endurance performance in trained male cyclists.
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Provide a general description of the methods as reported by the authors. Information should be extracted based on relevance to the SR (i.e., caffeine related methods) Participants: Ten moderately well-trained male cyclists able to cycle at a B-grade level or better volunteered for this study. To be classified as a B-grade or better cyclist a participant needed to attain a relative VO2max of 45–60 in the preexperimental testing, be regularly competing in races, and be training 10–12 hr/week. Only 8 participants completed the full trial; 2 failed to finish because of illness and personal commitments. All participants were nonsmokers. They were recruited via local cycle clubs and cycle shops in Hamilton, New Zealand. Each participant was fully informed about the nature of the investigation, the experimental procedures, and possible risks before giving informed, written consent. Experimental procedures and design: This study was designed as a three-way crossover, randomized, placebo-controlled, double-blinded study with three supplementation periods of 6 days and an exercise trial conducted on Day 6 of each supplementation period. Supplementation periods were separated by a washout period of 6–10 days. Each participant completed three exercise trials. Each trial consisted of 60 min of steady-state cycling at a workload equivalent to 60% VO2max, immediately followed by a maximal-effort 40-km cycling time trial. Pre-experimental period: Each participant’s Wmax and VO2max were determined before the actual exercise trials via an incremental cycle exercise test to volitional exhaustion. Participants also completed a familiarization 40-km cycling time trial before the experimental trials. A Polar heart-rate monitor (Polar Electro, Finland) was worn by the participants to measure heart rate during each test. Treatments: The three treatments were administered in a randomized, placebocontrolled, double-blind manner. The treatments were placebo (270 mg glucose powder), caffeine (3 mg/kg body mass), and green-tea extract (270 mg TEAVIGO). TEAVIGO is a highly purified extract from the leaves of green tea (Camellia sinensis) containing a minimum of 90% EGCG and a maximum of 0.1% caffeine. During each 6-day supplementation period participants consumed five capsules over 5 days (one capsule per day) and two capsules on Day 6. During the placebo period this equated to seven capsules of glucose powder, during the caffeine period it equated to five capsules of glucose powder and two caffeine capsules taken on Day 6, and during the green-tea period it was seven capsules of TEAVIGO EGCG.
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How many outcome-specific endpoints are evaluated? 1
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What is the (or one of the) endpoint(s) evaluated? (Each endpoint listed separately) Heart rate
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List additional health endpoints (separately). 2
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List additional health endpoints (separately).3
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List additional health endpoints (separately).4
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List additional health endpoints (separately).5
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List additional health endpoints (separately).6
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Clinical, physiological, other Physiological
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What is the study design? Controlled Trial
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Randomized or Non-Randomized? RCT
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What were the diagnostics or methods used to measure the outcome? Objective
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Optional: Name of Method or short description A Polar heart-rate monitor (Polar Electro, Finland) was worn by the participants to measure heart rate during each test.
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Caffeine (general) Caffeine (general)
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Coffee, Chocolate, energy drink, gum, medicine/supplement, soda, tea, other?
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Measured or self reported? Measured
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Children, adolescents, adults, or pregnant included? Adults
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What was the reference, comparison, or control group(s)? (e.g. high vs low consumption, number of cups, etc.) Placebo.
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What were the listed confounders or modifying factors as stated by the authors? (e.g. multi-variable components of models.  Copy from methods) Measures of centrality and spread are shown as M ± SD. Uncertainties in the estimates of effects are expressed as 90% confidence limits and as chances that the true value of the effect is practically beneficial, trivial, or harmful in relation to performance (Batterham & Hopkins, 2005). To calculate these chances, we assumed that the smallest worthwhile change in time-trial performance for a competitive cyclist is 1.0%. Thresholds for assigning qualitative terms to chances were as follows: <1%, almost certainly not; <5%, very unlikely; <25%, unlikely or probably not; <50%, possibly not; >50%, possibly; >75%, likely or probable; >95%, very likely; and >99%, almost certain. In addition, two-way analyses of variance were used to determine significant differences between variables at an alpha level of .05.
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What conflicts of interest were reported? Not discussed.
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Refid 20175431
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What were the sources of funding? The authors of this article would like to acknowledge the support of the Wintec Research Fund and DSM Nutritionals, Auckland, New Zealand, for supplying TEAVIGO.
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Results & Comparisons

No Results found.