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Florez CM, Prather J, Miller D, Vargas A, Soto B, Harrison A, Tinsley G, Taylor L. The Effects of Two Servings of a Thermogenic Supplement on Metabolism, Hemodynamic Variables, and Mood State Outcomes in Young Overweight Adults. Cureus 2024; 16:e54484. [PMID: 38516475 PMCID: PMC10954375 DOI: 10.7759/cureus.54484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/19/2024] [Indexed: 03/23/2024] Open
Abstract
Introduction We examined if acute ingestion of a novel thermogenic supplement influences resting energy expenditure (REE), mood, and hemodynamic function. Methods Forty-six adults completed this randomized, placebo-controlled, double-blind, crossover study. Participants underwent two conditions: placebo (PL) and treatment (TX) containing 300 mg of caffeine and 3 g of acetyl-L-carnitine. REE, systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR), and mood states were assessed at baseline and 30, 60, and 120 minutes post-ingestion. Data were analyzed using repeated measures analysis of variance. Results A significant condition-by-time interaction was observed for REE. At the 30-, 60-, and 120-minute post-ingestion timepoints, REE was 202 ± 26, 238 ± 40, and 209 ± 29 kcal/d greater in the TX condition compared to PL. No significant differences were observed for SBP and HR but a significant interaction indicated that DBP was elevated at 30 minutes in the TX vs. PL, though values remained within normal ranges. Significant interactions were observed for perceived alertness, concentration, energy, and focus, with increases in TX. Conclusion These data provide evidence that acute consumption of the thermogenic dietary supplement OxyShred (EHPlabs, Salt Lake City, Utah, USA) stimulates increases in REE that are sustained for ≥ two hours, along with increasing perceived alertness, concentration, energy, and focus. Changes in hemodynamic function are minimal and within normal ranges.
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Affiliation(s)
| | - Jessica Prather
- Human Performance Lab, University of Mary Hardin-Baylor, Belton, USA
| | - Dylon Miller
- Human Performance Lab, University of Mary Hardin-Baylor, Belton, USA
| | - Amie Vargas
- Human Performance Lab, University of Mary Hardin-Baylor, Belton, USA
| | - Bella Soto
- Human Performance Lab, University of Mary Hardin-Baylor, Belton, USA
| | - Abby Harrison
- Human Performance Lab, University of Mary Hardin-Baylor, Belton, USA
| | - Grant Tinsley
- Kinesiology & Sport Management, Texas Tech University, Lubbock, USA
| | - Lem Taylor
- Physiology and Nutrition, University of Mary Hardin-Baylor, Belton, USA
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Prather JM, Florez CM, Vargas A, Soto B, Harrison A, Willoughby D, Tinsley G, Taylor L. The effects of a thermogenic supplement on metabolic and hemodynamic variables and subjective mood states. J Int Soc Sports Nutr 2023; 20:2185538. [PMID: 36862833 PMCID: PMC9987759 DOI: 10.1080/15502783.2023.2185538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/04/2023] Open
Abstract
BACKGROUND Thermogenic supplements are widely used in the general population to support attempted fat loss; however, the efficacy and safety of these supplements are questioned. PURPOSE To determine whether a thermogenic supplement affects metabolic rate, hemodynamic responses, and mood states. METHODS In a randomized double-blind crossover design, 23 females (22.2 ± 3.5 years; 164.8 ± 6.4 cm; 73.5 ± 6.9 kg) who were moderate caffeine consumers (<150 mg/day) reported to the lab after a 12 h fast for baseline assessments of resting energy expenditure (REE) via indirect calorimetry, heart rate (HR), blood pressure (SBP and DBP), blood variables, and hunger, satiety, and mood states. Thereafter, subjects ingested the assigned treatment (active treatment containing caffeine, micronutrients, and phytochemicals [TR] or placebo [PL]). All variables were reassessed at 30-, 60-, 120-, and 180 min post-ingestion. Subjects repeated the same protocol with ingestion of the opposite treatment on a separate day. All data were analyzed using a 2 × 5 ANOVA with repeated measures and significance was accepted a priori at p < 0.05. RESULTS In the TR group, mean increases in REE of 121 to 166 kcal/d were observed at 30-, 60-, and 180 min post-ingestion (p < 0.01 for all). PL group mean decreases in REE of 72 to 91 kcal/day were observed at 60-, 120-, and 180 min (p < 0.05 for all). Respiratory quotient decreased at 120 and 180 min in both treatments. Slight increases in SBP of 3-4 mmHg were observed at 30, 120, and 180 min (p < 0.05 for all) post-ingestion of TR, while no effects were observed for DBP. Observed increases in SBP were within normal blood pressure ranges. TR decreased subjective fatigue with no other significant changes in mood states. Glycerol was maintained in TR, while there was a decrease at 30, 60, and 180 min (p < 0.05 for all) post-ingestion of PLA. Free fatty acids increased in TR at 60 and 180 min (p < 0.05) post-ingestion as well as a significant difference between treatments at 30 min post-ingestion indicating greater circulating free fatty acids levels in TR vs. PL (p < 0.01). CONCLUSION These findings indicate that ingestion of a specific thermogenic supplement formulation produces a sustained increase in metabolic rate and caloric expenditure and reduces fatigue over 3 h without producing adverse hemodynamic responses.
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Affiliation(s)
- Jessica M Prather
- University of Mary Hardin-Baylor, Human Performance Lab, School of Exercise and Sport Science, Belton, TX, USA
| | - Christine M Florez
- University of Mary Hardin-Baylor, Human Performance Lab, School of Exercise and Sport Science, Belton, TX, USA
| | - Amie Vargas
- University of Mary Hardin-Baylor, Human Performance Lab, School of Exercise and Sport Science, Belton, TX, USA
| | - Bella Soto
- University of Mary Hardin-Baylor, Human Performance Lab, School of Exercise and Sport Science, Belton, TX, USA
| | - Abby Harrison
- University of Mary Hardin-Baylor, Human Performance Lab, School of Exercise and Sport Science, Belton, TX, USA
| | - Darryn Willoughby
- University of Mary Hardin-Baylor, Human Performance Lab, School of Exercise and Sport Science, Belton, TX, USA
| | - Grant Tinsley
- Texas Tech University, Energy Balance & Body Composition Lab; Department of Kinesiology & Sport Management, Lubbock, TX, USA
| | - Lem Taylor
- University of Mary Hardin-Baylor, Human Performance Lab, School of Exercise and Sport Science, Belton, TX, USA
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Rodriguez C, Stratton MT, Harty PS, Siedler MR, Boykin JR, Green JJ, Keith DS, White SJ, DeHaven B, Brojanac A, Tinoco E, Taylor LW, Tinsley GM. Effects of a ready-to-drink thermogenic beverage on resting energy expenditure, hemodynamic function, and subjective outcomes. J Int Soc Sports Nutr 2023; 20:2211958. [PMID: 37162193 PMCID: PMC10173796 DOI: 10.1080/15502783.2023.2211958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/11/2023] Open
Abstract
BACKGROUND Thermogenic supplements are often consumed by individuals seeking to improve energy levels and reduce body fat. These supplements are sold in powdered or ready-to-drink (RTD) forms and consist of a blend of ingredients such as caffeine, green tea extract, and other botanical compounds. While there is evidence that thermogenic supplements can positively affect resting energy expenditure (REE), the effect varies based on the combination of active ingredients. Additionally, there is some concern that thermogenic supplements may cause unwanted side effects on hemodynamic variables, like heart rate (HR) and blood pressure (BP). Therefore, further investigation into the efficacy and safety of commercially available products is warranted. METHODS Twenty-eight individuals (14 F, 14 M; age: 23.3 ± 3.9 yrs; height: 169.4 ± 8.6 cm; body mass: 73.3 ± 13.1 kg) completed two visits in a randomized, double-blind, crossover fashion. Each visit began with baseline REE, HR, and BP assessments, which were followed by ingestion of an active RTD thermogenic beverage (RTD; OxyShred Ultra Energy) or placebo (PL). Assessments were repeated at the intervals of 35-50- and 85-100-minutes post-ingestion. In addition, subjective outcomes of energy, focus, concentration, alertness, and mood were collected five times throughout each visit. Repeated-measures analysis of variance was performed with condition and time specified as within-subjects factors and sex and resistance training (RT) status as between-subjects factors. Statistical significance was accepted at p < 0.05. RESULTS A significant condition × time interaction was observed for REE (p < 0.001). Higher REE values were demonstrated at 35-50 min (0.08 ± 0.02 kcal/min; p = 0.001; 5.2% difference) and 85-100 min (0.08 ± 0.02 kcal/min; p = 0.001; 5.5% difference) after RTD ingestion as compared to PL. No significant condition × time interactions were observed for respiratory quotient, HR, or BP. Condition main effects indicated lower HR (3.0 ± 0.9 bpm; p = 0.003), higher SBP (3.5 ± 1.1 mm Hg; p = 0.003) and higher DBP (3.5 ± 0.9 mm Hg; p < 0.001) in RTD as compared to PL, irrespective of time. Condition × time interactions were observed for all subjective outcomes (p ≤ 0.02). Post hoc tests indicated statistically significant benefits of the RTD over PL for energy, focus, concentration, and alertness, without significant differences for mood after correction for multiple comparisons. Sex and RT status were not involved in interactions for any outcomes, except for a Sex × RT status interaction for energy, indicating higher energy ratings in non-resistance-trained vs. resistance-trained males. CONCLUSIONS These data suggest that acute ingestion of a thermogenic RTD beverage significantly increases REE, and this elevated caloric expenditure is sustained for at least 100 minutes following ingestion. Furthermore, the RTD beverage increased measures of energy, focus, concentration, and alertness as compared to placebo. While minor differences in hemodynamic variables were observed between conditions, all values stayed within normal ranges. Individuals aiming to increase energy expenditure may benefit from acute ingestion of an RTD thermogenic supplement.
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Affiliation(s)
- Christian Rodriguez
- Texas Tech University, Energy Balance & Body Composition Laboratory; Department of Kinesiology & Sport Management, Lubbock, TX, USA
| | - Matthew T Stratton
- Texas Tech University, Energy Balance & Body Composition Laboratory; Department of Kinesiology & Sport Management, Lubbock, TX, USA
| | - Patrick S Harty
- Texas Tech University, Energy Balance & Body Composition Laboratory; Department of Kinesiology & Sport Management, Lubbock, TX, USA
| | - Madelin R Siedler
- Texas Tech University, Energy Balance & Body Composition Laboratory; Department of Kinesiology & Sport Management, Lubbock, TX, USA
| | - Jake R Boykin
- Texas Tech University, Energy Balance & Body Composition Laboratory; Department of Kinesiology & Sport Management, Lubbock, TX, USA
| | - Jacob J Green
- Texas Tech University, Energy Balance & Body Composition Laboratory; Department of Kinesiology & Sport Management, Lubbock, TX, USA
| | - Dale S Keith
- Texas Tech University, Energy Balance & Body Composition Laboratory; Department of Kinesiology & Sport Management, Lubbock, TX, USA
| | - Sarah J White
- Texas Tech University, Energy Balance & Body Composition Laboratory; Department of Kinesiology & Sport Management, Lubbock, TX, USA
| | - Brielle DeHaven
- Texas Tech University, Energy Balance & Body Composition Laboratory; Department of Kinesiology & Sport Management, Lubbock, TX, USA
| | - Alexandra Brojanac
- Texas Tech University, Energy Balance & Body Composition Laboratory; Department of Kinesiology & Sport Management, Lubbock, TX, USA
| | - Ethan Tinoco
- Texas Tech University, Energy Balance & Body Composition Laboratory; Department of Kinesiology & Sport Management, Lubbock, TX, USA
| | - Lem W Taylor
- University of Mary Hardin-Baylor, Human Performance Laboratory, School of Exercise and Sport Science, Belton, TX, USA
| | - Grant M Tinsley
- Texas Tech University, Energy Balance & Body Composition Laboratory; Department of Kinesiology & Sport Management, Lubbock, TX, USA
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Campbell BI, Perry R, Horsley J, Aguilar D, Shimshock T, Fox C, Vargas A, Colenso-Semple L. A Commercially Available Thermogenic Dietary Supplement Increases Resting Metabolic Rate in Physically Active Males: A Randomized, Double-Blind, Placebo-Controlled Investigation. J Diet Suppl 2018; 17:150-160. [DOI: 10.1080/19390211.2018.1494660] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
- Bill I. Campbell
- Performance and Physique Enhancement Laboratory, University of South Florida, Tampa, FL, USA
| | - Ross Perry
- Performance and Physique Enhancement Laboratory, University of South Florida, Tampa, FL, USA
| | - John Horsley
- Performance and Physique Enhancement Laboratory, University of South Florida, Tampa, FL, USA
| | - Danielle Aguilar
- Performance and Physique Enhancement Laboratory, University of South Florida, Tampa, FL, USA
| | - Taylor Shimshock
- Performance and Physique Enhancement Laboratory, University of South Florida, Tampa, FL, USA
| | - Carl Fox
- Performance and Physique Enhancement Laboratory, University of South Florida, Tampa, FL, USA
| | - Andres Vargas
- Performance and Physique Enhancement Laboratory, University of South Florida, Tampa, FL, USA
| | - Lauren Colenso-Semple
- Performance and Physique Enhancement Laboratory, University of South Florida, Tampa, FL, USA
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Kendall KL, Hyde PN, Fairman CM, Hollaway KM, Mumford PW, Haun CT, Mobley B, Kephart WC, Tribby AC, Kimber D, Moon JR, Beck DT, Roberts MD, Young KC. A Randomized, Double-Blind, Placebo-Controlled Trial to Determine the Effectiveness and Safety of a Thermogenic Supplement in Addition to an Energy-Restricted Diet in Apparently Healthy Females. J Diet Suppl 2017; 14:653-666. [DOI: 10.1080/19390211.2017.1304484] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
| | - Parker N. Hyde
- Department of Human Sciences, College of Education and Human Ecology, The Ohio State University, Columbus, OH, USA
| | - Ciaran M. Fairman
- Department of Human Sciences, College of Education and Human Ecology, The Ohio State University, Columbus, OH, USA
| | - Kaitlyn M. Hollaway
- Clinical Trials Unit, University of Kansas Medical Center - Wichita Campus, Wichita, KS, USA
| | - Petey W. Mumford
- Molecular and Applied Sciences Laboratory, School of Kinesiology, Auburn University, Auburn, AL, USA
| | - Cody T. Haun
- Molecular and Applied Sciences Laboratory, School of Kinesiology, Auburn University, Auburn, AL, USA
| | - Brooks Mobley
- Molecular and Applied Sciences Laboratory, School of Kinesiology, Auburn University, Auburn, AL, USA
| | - Wesley C. Kephart
- Molecular and Applied Sciences Laboratory, School of Kinesiology, Auburn University, Auburn, AL, USA
| | | | | | - Jordan R. Moon
- School of Health Sciences, American Public University System, Charles Town, WV, USA
| | - Darren T. Beck
- Department of Cell Biology and Physiology, Edward Via College of Osteopathic Medicine - Auburn Campus, Auburn, AL, USA
| | - Michael D. Roberts
- Molecular and Applied Sciences Laboratory, School of Kinesiology, Auburn University, Auburn, AL, USA
- Department of Cell Biology and Physiology, Edward Via College of Osteopathic Medicine - Auburn Campus, Auburn, AL, USA
| | - Kaelin C. Young
- Molecular and Applied Sciences Laboratory, School of Kinesiology, Auburn University, Auburn, AL, USA
- Department of Cell Biology and Physiology, Edward Via College of Osteopathic Medicine - Auburn Campus, Auburn, AL, USA
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Jung YP, Earnest CP, Koozehchian M, Galvan E, Dalton R, Walker D, Rasmussen C, Murano PS, Greenwood M, Kreider RB. Effects of acute ingestion of a pre-workout dietary supplement with and without p-synephrine on resting energy expenditure, cognitive function and exercise performance. J Int Soc Sports Nutr 2017; 14:3. [PMID: 28096758 PMCID: PMC5234109 DOI: 10.1186/s12970-016-0159-2] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Accepted: 12/16/2016] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND The purpose of this study was to examine the effects of acute ingestion of a pre-workout dietary supplement (PWS) with and without p-synephrine (S) on perceptions of readiness to perform, cognitive function, exercise performance, and markers of safety. METHODS In a randomized, double-blind, and counterbalanced manner; 25 healthy and recreationally active male and female participants ingested a flavored maltodextrin placebo (PLA), a PWS containing beta-alanine (3 g), creatine nitrate as a salt (2 g), arginine alpha-ketoglutarate (2 g), N-Acetyl-L-Tyrosine (300 mg), caffeine (284 mg), Mucuna pruiriens extract standardized for 15% L-Dopa (15 mg), Vitamin C as Ascorbic Acid (500 mg), niacin (60 mg), folate as folic acid (50 mg), and Vitamin B12 as Methylcobalamin (70 mg) with 2 g of maltodextrin and flavoring; or, the PWS with Citrus aurantium (PWS + S) extract standardized for 30% p-synephrine (20 mg). Participants had heart rate (HR), blood pressure, resting energy expenditure (REE), 12-lead electrocardiograms (ECG), perceptions about readiness to perform, cognitive function (Stroop Color-Word test), bench and leg press performance (2 sets of 10 repetitions at 70% of 1RM and 1 set to failure), and Wingate anaerobic capacity (WAC) sprint performance determined as well as donated blood samples prior to and/or following exercise/supplementation. Data were analyzed by MANOVA with repeated measures as well as mean changes from baseline with 95% confidence intervals (CI). RESULTS No clinically significant differences were observed among treatments in HR, blood pressure, ECG, or general clinical blood panels. There was evidence that PWS and PWS + S ingestion promoted greater changes in REE responses. Participants reported higher perception of optimism about performance and vigor and energy with PWS and PWS + S ingestion and there was evidence that PWS and PWS + S improved changes in cognitive function scores from baseline to a greater degree than PLA after 1 or 2 h. However, the scores in the PWS + S treatment did not exceed PLA or PWS responses at any data point. No statistically significant differences were observed among treatments in total bench press lifting volume, leg press lifting volume or WAC sprint performance. CONCLUSIONS Within the confines of this study, ingestion of PWS and/or PWS + S prior to exercise appears to be well-tolerated when consumed by young, healthy individuals. The primary effects appear to be to increase REE responses and improve perceptions about readiness to perform and cognitive function with limited to no effects on muscular endurance and WAC. The addition of 20 mg of p-synephrine to the PWS provided limited to no additive benefits. TRIAL REGISTRATION This trial (NCT02952014) was retrospectively registered on September 13th 2016.
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Affiliation(s)
- Y. Peter Jung
- Exercise & Sport Nutrition Lab, Department of Health & Kinesiology, Texas A&M University, College Station, TX 77843-4243 USA
| | - Conrad P. Earnest
- Exercise & Sport Nutrition Lab, Department of Health & Kinesiology, Texas A&M University, College Station, TX 77843-4243 USA
- Nutrabolt, Bryan, TX 77807 USA
| | - Majid Koozehchian
- Exercise & Sport Nutrition Lab, Department of Health & Kinesiology, Texas A&M University, College Station, TX 77843-4243 USA
| | - Elfego Galvan
- Exercise & Sport Nutrition Lab, Department of Health & Kinesiology, Texas A&M University, College Station, TX 77843-4243 USA
| | - Ryan Dalton
- Exercise & Sport Nutrition Lab, Department of Health & Kinesiology, Texas A&M University, College Station, TX 77843-4243 USA
| | - Dillon Walker
- Center for Translational Research in Aging and Longevity, Department of Health & Kinesiology, Texas A&M University, College Station, TX 77843-4243 USA
| | - Christopher Rasmussen
- Exercise & Sport Nutrition Lab, Department of Health & Kinesiology, Texas A&M University, College Station, TX 77843-4243 USA
| | - Peter S. Murano
- Institute for Obesity Research & Program Evaluation, Department of Nutrition and Food Sciences, Texas A&M University, College Station, TX 77843 USA
| | - Mike Greenwood
- Exercise & Sport Nutrition Lab, Department of Health & Kinesiology, Texas A&M University, College Station, TX 77843-4243 USA
| | - Richard B. Kreider
- Exercise & Sport Nutrition Lab, Department of Health & Kinesiology, Texas A&M University, College Station, TX 77843-4243 USA
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Campbell BI, Colquhoun RJ, Zito G, Martinez N, Kendall K, Buchanan L, Lehn M, Johnson M, St Louis C, Smith Y, Cloer B. The effects of a fat loss supplement on resting metabolic rate and hemodynamic variables in resistance trained males: a randomized, double-blind, placebo-controlled, cross-over trial. J Int Soc Sports Nutr 2016; 13:14. [PMID: 27042166 PMCID: PMC4818444 DOI: 10.1186/s12970-016-0125-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Accepted: 03/24/2016] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND While it is known that dietary supplements containing a combination of thermogenic ingredients can increase resting metabolic rate (RMR), the magnitude can vary based on the active ingredient and/or combination of active ingredients. The purpose of this study was to examine the effects of a commercially available thermogenic fat loss supplement on RMR and hemodynamic variables in healthy, resistance trained males. METHODS Ten resistance-trained male participants (29 ± 9 years; 178 ± 4 cm; 85.7 ± 11 kg, and BMI = 26.8 ± 3.7) volunteered to participate in this randomized, double-blind, placebo controlled cross-over study. Participants underwent two testing sessions separated by at least 24 h. On their first visit, participants arrived to the laboratory after an overnight fast and a 24-h avoidance of exercise, and underwent a baseline RMR, HR, and BP assessment. Next, each participant ingested a thermogenic fat loss supplement (TFLS) or a placebo (PLA) and repeated the RMR, HR, and BP assessments at 60, 120, and 180 min post-ingestion. During the second visit the alternative supplement was ingested and the assessments were repeated in the exact same manner. Data were analyzed via a 2-factor [2x4] within-subjects repeated measures analysis of variance (ANOVA). Post-hoc tests were analyzed via paired samples t-tests. The criterion for significance was set at p ≤ 0.05. RESULTS A significant main effect for time relative to raw RMR data (p = 0.014) was observed. Post-hoc analysis revealed that the TFLS significantly increased RMR at 60-min, 120-min, and 180-min post ingestion (p < 0.05) as compared to baseline RMR values. No significant changes in RMR were observed for the PLA treatment (p > 0.05). Specifically, RMR was increased by 7.8 % (from 1,906 to 2,057 kcal), 6.9 % (from 1,906 to 2,037 kcal), and 9.1 % (from 1,906 to 2,081 kcal) in the TFLS, while the PLA treatment increased RMR by 3.3 % (from 1,919 to 1,981 kcal), 3.1 % (from 1,919 to 1,978 kcal), and 2.1 % (from 1,919 to 1,959 kcal) above baseline at 60, 120, and 180-min post ingestion, respectively. Additionally, the TFLS significantly elevated RMR at the 3-h time point as compared to the PLA treatment (2,081 vs 1,959 kcal, p = 0.034). A main effect for groups was observed for systolic blood pressure, and a significant interaction and main effect for time were observed for diastolic blood pressure. It should be noted that although changes in diastolic blood pressure were significant, all values stayed within normal clinical ranges (<80 mmHg). CONCLUSIONS The TFLS led to significant elevations in RMR as compared to baseline. These elevations came with no adverse effect relative to resting heart rate, but a slight increase in blood pressure values. Taken on a daily basis, this TFLS may increase an individual's overall energy expenditure, however; future studies should investigate if this leads to a reduction in fat mass loss over time.
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Affiliation(s)
- Bill I Campbell
- Exercise Science Program, Performance & Physique Enhancement Laboratory, College of Education, University of South Florida, Tampa, FL 33620 USA
| | - Ryan J Colquhoun
- Exercise Science Program, Performance & Physique Enhancement Laboratory, College of Education, University of South Florida, Tampa, FL 33620 USA
| | - Gina Zito
- Exercise Science Program, Performance & Physique Enhancement Laboratory, College of Education, University of South Florida, Tampa, FL 33620 USA
| | - Nic Martinez
- Exercise Science Program, Performance & Physique Enhancement Laboratory, College of Education, University of South Florida, Tampa, FL 33620 USA
| | | | - Laura Buchanan
- Exercise Science Program, Performance & Physique Enhancement Laboratory, College of Education, University of South Florida, Tampa, FL 33620 USA
| | - Matt Lehn
- Exercise Science Program, Performance & Physique Enhancement Laboratory, College of Education, University of South Florida, Tampa, FL 33620 USA
| | - Mallory Johnson
- Exercise Science Program, Performance & Physique Enhancement Laboratory, College of Education, University of South Florida, Tampa, FL 33620 USA
| | - Courtney St Louis
- Exercise Science Program, Performance & Physique Enhancement Laboratory, College of Education, University of South Florida, Tampa, FL 33620 USA
| | - Yasmin Smith
- Exercise Science Program, Performance & Physique Enhancement Laboratory, College of Education, University of South Florida, Tampa, FL 33620 USA
| | - Brad Cloer
- Exercise Science Program, Performance & Physique Enhancement Laboratory, College of Education, University of South Florida, Tampa, FL 33620 USA
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Campbell BI, Zito G, Colquhoun R, Martinez N, Kendall K, Buchanan L, Lehn M, Johnson M, St Louis C, Smith Y, Cloer B, Pingel A. The effects of a single-dose thermogenic supplement on resting metabolic rate and hemodynamic variables in healthy females--a randomized, double-blind, placebo-controlled, cross-over trial. J Int Soc Sports Nutr 2016; 13:13. [PMID: 27034624 PMCID: PMC4815210 DOI: 10.1186/s12970-016-0123-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Accepted: 03/15/2016] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Recent investigations have identified that commercially available dietary supplements, containing a combination of thermogenic ingredients, can increase resting metabolic rate (RMR). Thermogenic dietary supplements can have a positive influence on RMR, but the magnitude can vary based on the active ingredient and/or combination of active ingredients. Additionally, further safety evaluation is needed on multi-ingredient supplements that contain caffeine, due to its potential effect on heart rate (HR) and blood pressure (BP). The purpose of this study was to examine the effects of a commercially available dietary supplement on RMR and hemodynamic variables in healthy females. METHODS 13 female participants (26.1 ± 11.3 years; 163.4 ± 9.1 cm; 63.7 ± 8.0 kg, and 24 ± 5 BMI) volunteered to participate in this investigation. Participants underwent two testing sessions separated by approximately 7 days. On their first visit, participants arrived to the laboratory after an overnight fast and underwent a baseline RMR, HR, and BP assessment. Next, each participant ingested a thermogenic dietary supplement or placebo and repeated the RMR, HR, and BP assessments at 60, 120, and 180-minutes post-ingestion. Approximately 1-week later, the alternative supplement was ingested and the assessments were repeated in the exact same manner. Data were analyzed via a 2-factor [2x4] within-subjects repeated measures analysis of variance (ANOVA). Post-hoc tests were analyzed via paired samples t-tests. RESULTS Repeated measures ANOVA revealed a significant effect for time relative to raw RMR data. Post-hoc analysis revealed that the dietary supplement treatment significantly increased RMR at 60-minutes, 120-minutes, and 180-minutes post ingestion (p < 0.05) as compared to baseline RMR values. No changes in RMR were observed for the placebo treatment (p > 0.05). Heart rate was not significantly affected at any time point with either supplement; however, main effects of treatment and time were observed for both systolic and diastolic blood pressure (p < 0.05). CONCLUSIONS The thermogenic dietary supplement treatment experienced greater elevations in RMR as compared to baseline. Due to the slight elevations in blood pressure, caution should be taken for those with increased risk for hypertension or pre-hypertension. Taken on a daily basis, thermogenic dietary supplementation may increase overall energy expenditure, potentially leading to reductions in fat mass over time.
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Affiliation(s)
- Bill I Campbell
- Exercise Science Program, Performance & Physique Enhancement Laboratory, College of Education, University of South Florida, Tampa, FL 33620 USA
| | - Gina Zito
- Exercise Science Program, Performance & Physique Enhancement Laboratory, College of Education, University of South Florida, Tampa, FL 33620 USA
| | - Ryan Colquhoun
- Exercise Science Program, Performance & Physique Enhancement Laboratory, College of Education, University of South Florida, Tampa, FL 33620 USA
| | - Nic Martinez
- Exercise Science Program, Performance & Physique Enhancement Laboratory, College of Education, University of South Florida, Tampa, FL 33620 USA
| | | | - Laura Buchanan
- Exercise Science Program, Performance & Physique Enhancement Laboratory, College of Education, University of South Florida, Tampa, FL 33620 USA
| | - Matt Lehn
- Exercise Science Program, Performance & Physique Enhancement Laboratory, College of Education, University of South Florida, Tampa, FL 33620 USA
| | - Mallory Johnson
- Exercise Science Program, Performance & Physique Enhancement Laboratory, College of Education, University of South Florida, Tampa, FL 33620 USA
| | - Courtney St Louis
- Exercise Science Program, Performance & Physique Enhancement Laboratory, College of Education, University of South Florida, Tampa, FL 33620 USA
| | - Yasmin Smith
- Exercise Science Program, Performance & Physique Enhancement Laboratory, College of Education, University of South Florida, Tampa, FL 33620 USA
| | - Brad Cloer
- Exercise Science Program, Performance & Physique Enhancement Laboratory, College of Education, University of South Florida, Tampa, FL 33620 USA
| | - Allison Pingel
- Exercise Science Program, Performance & Physique Enhancement Laboratory, College of Education, University of South Florida, Tampa, FL 33620 USA
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Ratamess NA, Bush JA, Kang J, Kraemer WJ, Stohs SJ, Nocera VG, Leise MD, Diamond KB, Faigenbaum AD. The effects of supplementation with P-Synephrine alone and in combination with caffeine on resistance exercise performance. J Int Soc Sports Nutr 2015; 12:35. [PMID: 26388707 PMCID: PMC4573476 DOI: 10.1186/s12970-015-0096-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Accepted: 09/02/2015] [Indexed: 01/27/2023] Open
Abstract
BACKGROUND Little is known concerning the potential ergogenic effects of p-synephrine supplementation. Therefore, the purpose of the present study was to examine the effects of supplementation with p-synephrine alone and in combination with caffeine on free-weight resistance exercise performance. METHODS Twelve healthy, college-aged men performed a control (CT) resistance exercise protocol consisting of 6 sets of squats for up to 10 repetitions per set using 80% of their one repetition-maximum (1RM) with 2 min of rest in between sets. Each subject was randomly assigned (in double-blind, balanced manner) to a treatment sequence consisting of use of 3 supplements: p-synephrine (S; 100 mg), p-synephrine + caffeine (SCF; 100 mg of p-synephrine plus 100 mg of caffeine), or a placebo (P). For each supplement treatment (separated by 1 week), subjects consumed the supplement for 3 days prior to each protocol and the morning of each protocol, and subsequently did not consume any supplements for 3 days following (i.e. wash-out period). On each protocol day, subjects reported to the lab at a standard time, consumed a supplement, sat quietly for 45 min, performed the resistance exercise protocol, and sat quietly for 30 min post exercise. Performance (repetition number, force, velocity and power), blood lactate, and ratings of perceived exertion (RPE) data were collected during each protocol. RESULTS Supplements SCF and S produced a significantly (P < 0.05) greater number of repetitions performed than CT (by 11.0 ± 8.0%) and P (by 6.0 ± 7.0%) and a 10.6 ± 12.0% greater increase in volume load per protocol than CT and P. Most of the differences were seen during the last 3 sets. Mean power and velocity for all 6 sets were significantly higher in SCF compared to CT and P by ~6.2 ± 8.0%. No supplement effects were observed in RPE or blood lactate, and no adverse side effects were observed or reported. CONCLUSIONS S and SCF augmented resistance exercise performance (total repetitions, volume load) without increasing blood lactate or RPE. The addition of caffeine in SCF increased mean power and velocity of squat performance. These results indicate supplementation with S and SCF can enhance local muscle endurance during resistance exercise.
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Affiliation(s)
- Nicholas A. Ratamess
- />Department of Health and Exercise Science, The College of New Jersey, Ewing, NJ 08628 USA
| | - Jill A. Bush
- />Department of Health and Exercise Science, The College of New Jersey, Ewing, NJ 08628 USA
| | - Jie Kang
- />Department of Health and Exercise Science, The College of New Jersey, Ewing, NJ 08628 USA
| | - William J. Kraemer
- />Department of Human Sciences, The Ohio State University, Columbus, OH 43210 USA
| | - Sidney J. Stohs
- />School of Pharmacy and Health Professions, Creighton University, Omaha, NE 68178 USA
| | - Vincenzo G. Nocera
- />Department of Health and Exercise Science, The College of New Jersey, Ewing, NJ 08628 USA
| | - Megan D. Leise
- />Department of Health and Exercise Science, The College of New Jersey, Ewing, NJ 08628 USA
| | - Keith B. Diamond
- />Department of Health and Exercise Science, The College of New Jersey, Ewing, NJ 08628 USA
| | - Avery D. Faigenbaum
- />Department of Health and Exercise Science, The College of New Jersey, Ewing, NJ 08628 USA
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10
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Bergstrom HC, Housh TJ, Traylor DA, Lewis RW, Cochrane KC, Jenkins NDM, Schmidt RJ, Johnson GO, Housh DJ, Cramer JT. Metabolic, cardiovascular, and perceptual responses to a thermogenic nutritional supplement at rest, during exercise, and recovery in men. J Strength Cond Res 2014; 28:2154-63. [PMID: 24513614 DOI: 10.1519/jsc.0000000000000369] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Twenty-one men (mean ± SD; age = 23.5 ± 2.6 years, BMI = 26.0 ± 2.4 kg-1·m-2) completed this randomized, double-blinded, placebo-controlled, crossover study to examine acute responses to a thermogenic nutritional supplement. Each testing session included: (a) 30 minutes resting, followed by placebo or thermogenic nutritional supplementation, (b) 50 minutes postsupplementation resting, (c) 60 minutes walking, and (d) 50 minutes postexercise recovery. Gas exchange variables and heart rate (HR) were recorded during each phase. Blood pressure was recorded during all phases except exercise. Ratings of perceived exertion (RPE) were recorded only during exercise. There were no significant differences for any of the measures between the supplement and placebo during the initial resting or postsupplementation phases. During exercise, energy expenditure (EE) (placebo = 18.98-19.06 kJ·min-1 and supplement = 19.44-19.82 kJ·min-1) and VO2 (placebo = 11.27-11.35 ml·kg-1·min-1; supplement = 11.64-11.82 ml·kg-1·min-1) were greater for the supplement than placebo. There were no differences in respiratory exchange ratio (RER), HR, or RPE between the supplement and placebo during exercise. Postexercise, only VO2 (placebo = 3.53-3.63 ml·kg-1·min-1; supplement = 3.71-3.84 ml·kg-1·min-1) was greater for the supplement than placebo, but there were no differences in EE, RER, HR, or blood pressure. These findings suggested that the specific blend of ingredients in the thermogenic nutritional supplement, when combined with exercise, increased the metabolic rate with minimal changes in cardiovascular function and no effect on RPE.
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Affiliation(s)
- Haley C Bergstrom
- 1Department of Nutrition and Health Sciences, University of Nebraska-Lincoln, Lincoln, Nebraska; and 2College of Dentistry, University of Nebraska Medical Center, Lincoln, Nebraska
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11
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Effects of commercially available dietary supplements on resting energy expenditure: a brief report. ISRN NUTRITION 2014; 2014:650264. [PMID: 24967272 PMCID: PMC4045300 DOI: 10.1155/2014/650264] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/18/2013] [Accepted: 10/10/2013] [Indexed: 12/31/2022]
Abstract
Commercially available dietary products advertised to promote weight loss are an underresearched but heavily purchased commodity in the United States. Despite only limited evidence, interest in dietary supplements continues to increase. This work uniquely summarizes the current evidence evaluating the efficacy of several over-the-counter thermogenic products for their effects on resting energy expenditure. Currently, there is some evidence suggesting dietary products containing select ingredients can increase energy expenditure in healthy young people immediately following consumption (within 6 hours). It is unclear if supplement-induced increases in metabolic rate provide additional benefit beyond that provided by dietary constituents that contain similar ingredients. It is also unclear if dietary supplements are effective for weight loss in humans.
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12
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Bergstrom HC, Housh TJ, Traylor DA, Lewis RW, Jenkins NDM, Cochrane KC, Schmidt RJ, Johnson GO, Housh DJ. Physiologic responses to a thermogenic nutritional supplement at rest, during low-intensity exercise, and during recovery from exercise in college-aged women. Appl Physiol Nutr Metab 2013; 38:988-95. [PMID: 23905665 DOI: 10.1139/apnm-2013-0029] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This study examined acute physiologic responses to a thermogenic nutritional supplement at rest, during exercise, and during recovery from exercise in women. Twelve women (mean ± SD age, 22.9 ± 3.1 years) were recruited for this randomized, double-blinded, placebo-controlled, crossover study. Each testing session consisted of 4 phases: 30 min of presupplementation resting, followed by the ingestion of the placebo or thermogenic nutritional supplement; 50 min of postsupplementation resting; 60 min of walking (at 3.2-4.8 km·h(-1)); and 50 min of postexercise resting. Energy expenditure (EE), oxygen consumption, respiratory exchange ratio (RER), oxygen (O2) pulse, and heart rate (HR) values were recorded during all 4 phases. Systolic (SBP) and diastolic (DBP) blood pressure were recorded during the rest, postsupplementation, and postexercise recovery phases; ratings of perceived exertion (RPE) were recorded only during exercise. There were no significant differences for EE, oxygen consumption, O2 pulse, HR, SBP, or DBP between the supplement and placebo during the presupplementation resting or postsupplementation phases. The RER, however, was higher with the supplement at 30 min postsupplementation. During exercise, EE and O2 pulse were 3%-6% greater with the supplement than placebo; there were no significant differences in RPE. Postexercise, EE, oxygen consumption, and DBP were 3%-7% greater with the supplement than placebo. These findings suggest that a thermogenic nutritional supplement, when combined with exercise, increases metabolic rate but has no effect on the perception of effort and results in only minimal changes in cardiovascular function.
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Affiliation(s)
- Haley C Bergstrom
- a Human Performance Laboratory, Department of Nutrition and Health Sciences, University of Nebraska-Lincoln, 110 Ruth Leverton Hall, Lincoln, NE 68583-0806, USA
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13
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Outlaw J, Wilborn C, Smith A, Urbina S, Hayward S, Foster C, Wells S, Wildman R, Taylor L. Effects of ingestion of a commercially available thermogenic dietary supplement on resting energy expenditure, mood state and cardiovascular measures. J Int Soc Sports Nutr 2013; 10:25. [PMID: 23627832 PMCID: PMC3651299 DOI: 10.1186/1550-2783-10-25] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2013] [Accepted: 04/16/2013] [Indexed: 11/30/2022] Open
Abstract
Background Increasing metabolism is a primary focus of many commercially available dietary supplements marketed to support weight management. Caffeine (e.g. anhydrous and herbal) and green tea are key ingredients in such products, augmenting resting energy expenditure (REE) and improving reported mood states (alertness, fatigue, focus, etc.). The purpose of this study was to evaluate the effects of a thermogenic dietary supplement (DBX) on REE, respiratory exchange ratio (RER), reported measures of alertness, focus, energy, concentration, fatigue, and hunger, as well as the general safety of the product based on electrocardiogram (ECG) and hemodynamic responses in habitual caffeine consumers. Methods Six male and six female subjects (mean ± SD; 22.50 ± 3.22 years; 76.94 ± 14.78 kg; 22.7 ± 9.5% body fat), physically active (≥12 months), and moderate habitual caffeine consumers (<200 mg/day) received either two capsules of DBX containing 340 mg of total caffeine plus green tea extract, yerba mate extract, carnitine tartrate and other active ingredients or a placebo (PLC) in a double-blinded, crossover design. Heart rate (HR), blood pressure (BP), REE, RER and perceived mood states were measured at baseline and then hourly for four hours after ingesting either treatment. Results Resting energy expenditure was significantly increased at all four time points and significant increases were determined for perceived alertness (p = 0.026) and focus (p = 0.05) at hour 1 and for energy at 1 and 2 hours after treatment for the DBX group (p = 0.008 and p = 0.017, respectively). Additionally, perceived fatigue was decreased at the hour 1 assessment (p = 0.010). No significant differences were seen between DBX and placebo for hunger, anxiety, HR, BP, ECG patterns or RER. Conclusions The results of this investigation support that the proprietary blend of this thermogenic aid is capable of increasing REE for four hours post-ingestion while supporting increased focus, alertness, and energy as well as decreasing fatigue without promoting anxiety or causing significant changes in HR, BP, or ECG measurements in habitual caffeine consumers.
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Affiliation(s)
- Jordan Outlaw
- Human Performance Lab, Department of Exercise and Sport Science, University of Mary Hardin-Baylor, Human Performance Lab, Belton, TX, 76513, USA.
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14
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Campbell B, Wilborn C, La Bounty P, Taylor L, Nelson MT, Greenwood M, Ziegenfuss TN, Lopez HL, Hoffman JR, Stout JR, Schmitz S, Collins R, Kalman DS, Antonio J, Kreider RB. International Society of Sports Nutrition position stand: energy drinks. J Int Soc Sports Nutr 2013; 10:1. [PMID: 23281794 PMCID: PMC3538552 DOI: 10.1186/1550-2783-10-1] [Citation(s) in RCA: 114] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2012] [Accepted: 12/31/2012] [Indexed: 12/18/2022] Open
Abstract
Position Statement: The International Society of Sports Nutrition (ISSN) bases the following position stand on a critical analysis of the literature on the safety and efficacy of the use of energy drinks (ED) or energy shots (ES). The ISSN has concluded the following. 1. Although ED and ES contain a number of nutrients that are purported to affect mental and/or physical performance, the primary ergogenic nutrients in most ED and ES appear to be carbohydrate and/or caffeine. 2. The ergogenic value of caffeine on mental and physical performance has been well-established but the potential additive benefits of other nutrients contained in ED and ES remains to be determined. 3. Consuming ED 10-60 minutes before exercise can improve mental focus, alertness, anaerobic performance, and/or endurance performance. 4. Many ED and ES contain numerous ingredients; these products in particular merit further study to demonstrate their safety and potential effects on physical and mental performance. 5. There is some limited evidence that consumption of low-calorie ED during training and/or weight loss trials may provide ergogenic benefit and/or promote a small amount of additional fat loss. However, ingestion of higher calorie ED may promote weight gain if the energy intake from consumption of ED is not carefully considered as part of the total daily energy intake. 6. Athletes should consider the impact of ingesting high glycemic load carbohydrates on metabolic health, blood glucose and insulin levels, as well as the effects of caffeine and other stimulants on motor skill performance. 7. Children and adolescents should only consider use of ED or ES with parental approval after consideration of the amount of carbohydrate, caffeine, and other nutrients contained in the ED or ES and a thorough understanding of the potential side effects. 8. Indiscriminant use of ED or ES, especially if more than one serving per day is consumed, may lead to adverse events and harmful side effects. 9. Diabetics and individuals with pre-existing cardiovascular, metabolic, hepatorenal, and neurologic disease who are taking medications that may be affected by high glycemic load foods, caffeine, and/or other stimulants should avoid use of ED and/or ES unless approved by their physician.
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Affiliation(s)
- Bill Campbell
- Exercise and Performance Nutrition Laboratory, Dept. of Physical Education and Exercise Science, University of South Florida, 4202 E. Fowler Avenue, PED 214, Tampa, FL, 33620, USA
| | - Colin Wilborn
- Human Performance Laboratory, University of Mary Hardin-Baylor, Belton, TX, 76513, USA
| | - Paul La Bounty
- Department of Health, Human Performance, and Recreation, Baylor University, Box 97313, Waco, TX, 76798, USA
| | - Lem Taylor
- Human Performance Laboratory, University of Mary Hardin-Baylor, Belton, TX, 76513, USA
| | - Mike T Nelson
- Department of Health and Human Performance, University of St.Thomas, St. Paul, MN, 55105, USA
| | - Mike Greenwood
- Exercise & Sport Nutrition Lab, Department of Health & Kinesiology, Texas A&M University, College Station, Texas, TX, 77843-4243, USA
| | | | - Hector L Lopez
- The Center for Applied Health Sciences, Stow, OH, 44224, USA
| | - Jay R Hoffman
- Institute of Exercise Physiology and Wellness, Department of Sport and Exercise Science, University of Central Florida, Orlando, FL, 32816, USA
| | - Jeffrey R Stout
- Institute of Exercise Physiology and Wellness, Department of Sport and Exercise Science, University of Central Florida, Orlando, FL, 32816, USA
| | - Stephen Schmitz
- Medical Surveillance and Risk Management, Shire HGT, 300 Shire Way, Lexington, MA, 02421, USA
| | | | - Doug S Kalman
- Miami Research Associates, Endocrinology & Nutrition Department, 6141 Sunset Drive - Suite 301, Miami, FL, 33143, USA
| | - Jose Antonio
- Farquhar College of Arts and Sciences, Nova Southeastern University, Fort Lauderdale, FL, USA
| | - Richard B Kreider
- Exercise & Sport Nutrition Lab, Department of Health & Kinesiology, Texas A&M University, College Station, Texas, TX, 77843-4243, USA
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15
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The effect of a stimulation drink on metabolic rate and haemodynamic parameters in comparison to a caffeinated placebo: a randomised, crossover, double blinded study. Proc Nutr Soc 2012. [DOI: 10.1017/s0029665112001280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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