Study Preview
Study Title and Description
Low-dose caffeine administered in chewing gum does not enhance cycling to exhaustion.
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? |
|
Primary Publication Information
-
Comments (0) | - Post/View
| Title | Low-dose caffeine administered in chewing gum does not enhance cycling to exhaustion. |
| Author | EJ Ryan,CH Kim,MD Muller,DM Bellar,JE Barkley,MV Bliss,A Jankowski-Wilkinson,M Russell,R Otterstetter,D Macander,EL Glickman,GH Kamimori, |
| Country | |
| Year | 2012 |
| Numbers |
Secondary Publication Information
There are currently no secondary publications defined for this study.
Extraction Form: Cardiovascular Design
| Question... Follow Up | Answer | Follow-up Answer | |
|---|---|---|---|
| What outcome is being evaluated in this paper? | Cardiovascular |
|
|
| What is the objective of the study (as reported by the authors)? | The purpose of the current investigation was to examine the effect of low-dose caffeine (CAF) administered in chewing gum at 3 different time points during submaximal cycling exercise to exhaustion. |
|
|
| 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) | Caffeine was administered at 1 time point in 3 trials and placebo was administered at all time points in a control trial to allow for comparisons between trials. Stay AlertTM chewing gum (Mastix Medica LLC) was used in the current investigation as previous studies conducted to determine the pharmacokinetics of caffeine administered in chewing gum used this product. To control for possible sources of error variance, caffeine was administered in a double-blind manner, and the order in which subjects completed the trials was randomized. This study employed a placebo controlled, randomized, double-blind, within-subjects design. The subjects participated in 4 experimental trials with a 1-week washout period between trials. During each of the trials, 2 pieces of chewing gum (CAFor PLA) were administered at 3 time points, 35 minutes pre-exercise, 5 minutes pre-exercise, and 15 minutes after the initiation of exercise. These time points were selected based on the pharmacokinetics ofCAFadministered in chewing gum (27,38) and an anticipated mean cycle time of approximately 30 minutes. The subjects chewed for 5minutes, and then the gum was expectorated. In 3 of the 4 experimental trials, CAF was administered at 1 of the 3 time points (235 minutes [trial A], 25 minutes [trial B], 15 minutes into exercise [trial C]) and PLA at the other 2 time points. During the control trial (trial D), PLA gum was administered at all 3 time points. One piece of Stay AlertTM chewing gum (Mastix Medica LLC) contains 100 mg of CAF, and it has been reported that 85% of the dose is released and absorbed during the first 5minutes of chewing (27). Thus, it was speculated that the subjects ingested approximately 170mg of CAF. The PLA and CAF gum were virtually identical in shape, texture, flavor, and color. Figure 1 provides an overview of the experimental protocol. Heart rate measures were obtained using a Polar HR monitor (Accurex Plus, Polar Electro, Inc., Woodbury, NY, USA). HR was obtained at baseline and every 10 minutes during cycling. |
|
|
| How many outcome-specific endpoints are evaluated? | 1 |
|
|
| What is the (or one of the) endpoint(s) evaluated? (Each endpoint listed separately) | Heart rate |
|
|
| List additional health endpoints (separately). 2 |
|
||
| List additional health endpoints (separately).3 |
|
||
| List additional health endpoints (separately).4 |
|
||
| List additional health endpoints (separately).5 |
|
||
| List additional health endpoints (separately).6 |
|
||
| Clinical, physiological, other | Physiological |
|
|
| What is the study design? | Controlled Trial |
|
|
| Randomized or Non-Randomized? | RCT |
|
|
| What were the diagnostics or methods used to measure the outcome? | Objective |
|
|
| Optional: Name of Method or short description | Heart rate measures were obtained using a Polar HR monitor (Accurex Plus, Polar Electro, Inc., Woodbury, NY, USA). HR was obtained at baseline and every 10 minutes during cycling. |
|
|
| Caffeine (general) |
|
||
| Coffee, Chocolate, energy drink, gum, medicine/supplement, soda, tea, other? |
|
||
| Measured or self reported? | Measured |
|
|
| Children, adolescents, adults, or pregnant included? | Adults |
|
|
| What was the reference, comparison, or control group(s)? (e.g. high vs low consumption, number of cups, etc.) | Placebo gum with no caffeine. |
|
|
| What were the listed confounders or modifying factors as stated by the authors? (e.g. multi-variable components of models. Copy from methods) | Potential volunteers were excluded from the study if they had a history of smoking; had signs or symptoms of cardiovascular, metabolic, or respiratory disease; or if they had any cardiovascular, metabolic, or respiratory disease as determined via a health history questionnaire. Time-to-exhaustion data were evaluated using a repeated measures analysis of variance (ANOVA). Serum FFA and plasma EPI and NE data were analyzed using a trial (A, B, C, D) by time (240, 210, post) ANOVA with repeated measures on both variables. Oxygen consumption, RER, HR, GLU, LA, RPE, and LP data were also analyzed using a trial (A, B, C, D) by time (245, +10, +20, +30) ANOVA with repeated measures on both variables. Significant main effects were further explored via paired samples t-tests corrected with Bonferroni adjustments. |
|
|
| What conflicts of interest were reported? | Not discussed. |
|
|
| Refid | 22293680 |
|
|
| What were the sources of funding? | Not discussed. |
|
Results & Comparisons
No Results found.
, means that you are leaving this Federal Government Web site and entering a non-Federal Web site.