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1.
J Int Soc Sports Nutr ; 20(1): 2237952, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37498180

RESUMEN

Based on review and critical analysis of the literature regarding the contents and physiological effects of coffee related to physical and cognitive performance conducted by experts in the field and selected members of the International Society of Sports Nutrition (ISSN), the following conclusions represent the official Position of the Society:(1) Coffee is a complex matrix of hundreds of compounds. These are consumed with broad variability based upon serving size, bean type (e.g. common Arabica vs. Robusta), and brew method (water temperature, roasting method, grind size, time, and equipment).(2) Coffee's constituents, including but not limited to caffeine, have neuromuscular, antioxidant, endocrine, cognitive, and metabolic (e.g. glucose disposal and vasodilation) effects that impact exercise performance and recovery.(3) Coffee's physiologic effects are influenced by dose, timing, habituation to a small degree (to coffee or caffeine), nutrigenetics, and potentially by gut microbiota differences, sex, and training status.(4) Coffee and/or its components improve performance across a temporal range of activities from reaction time, through brief power exercises, and into the aerobic time frame in most but not all studies. These broad and varied effects have been demonstrated in men (mostly) and in women, with effects that can differ from caffeine ingestion, per se. More research is needed.(5) Optimal dosing and timing are approximately two to four cups (approximately 473-946 ml or 16-32 oz.) of typical hot-brewed or reconstituted instant coffee (depending on individual sensitivity and body size), providing a caffeine equivalent of 3-6 mg/kg (among other components such as chlorogenic acids at approximately 100-400 mg per cup) 60 min prior to exercise.(6) Coffee has a history of controversy regarding side effects but is generally considered safe and beneficial for healthy, exercising individuals in the dose range above.(7) Coffee can serve as a vehicle for other dietary supplements, and it can interact with nutrients in other foods.(8) A dearth of literature exists examining coffee-specific ergogenic and recovery effects, as well as variability in the operational definition of "coffee," making conclusions more challenging than when examining caffeine in its many other forms of delivery (capsules, energy drinks, "pre-workout" powders, gum, etc.).


Asunto(s)
Rendimiento Atlético , Café , Masculino , Femenino , Humanos , Cafeína/farmacología , Rendimiento Atlético/fisiología , Ácido Clorogénico/análisis , Ejercicio Físico
2.
J Strength Cond Res ; 37(8): e444-e454, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37184967

RESUMEN

ABSTRACT: Escalante, G, Barakat, C, Tinsley, GM, and Schoenfeld, BJ. Nutrition, training, supplementation, and performance-enhancing drug practices of male and female physique athletes peaking for competition. J Strength Cond Res 37(8): e444-e454, 2023-The purpose of this descriptive investigation was threefold: (a) to assess the nutrition, training, supplement, and performance-enhancement drug practices of male and female physique competitors 30 days before competition; (b) to examine the specific water and macronutrient manipulation performed by competitors during the last 3 days before competition; and (c) to assess physiological responses to precontest preparation including body composition, body fluids, resting heart rate, and blood pressure. Competitors reported performing moderately high volume, moderate to high repetition, split-body resistance training programs performed on most days of the week; the programs included the use of a variety of advanced training methods. A majority of competitors included cardio to expedite fat loss, and most reported performing cardio in a fasted state despite a lack of objective evidentiary support for the practice. Competitors substantially restricted calories and consumed protein in amounts well above research-based guidelines (>3 g·kg -1 ·d -1 ); carbohydrate and lipid intake were highly variable. Water was substantially reduced in the final 3 days before competition. Competitors used a variety of dietary supplements throughout the study period, many of which are not supported by research. Both male and female competitors reported using performance enhancing drugs (∼48 and ∼38%, respectively) including testosterone derivatives, selective androgen receptor modulators, and human growth hormone. More research is warranted to elucidate safer and more effective peak week practices for physique competitors.


Asunto(s)
Sustancias para Mejorar el Rendimiento , Humanos , Masculino , Femenino , Estado Nutricional , Atletas , Suplementos Dietéticos , Agua
4.
J Int Soc Sports Nutr ; 17(1): 45, 2020 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-32831109

RESUMEN

BACKGROUND: Energy drinks are often consumed by the general population, as well as by active individuals seeking to enhance exercise performance and augment training adaptations. However, limited information is available regarding the efficacy of these products. Thus, the purpose of this study was to determine the effects of a commercially available caffeine- and protein-containing energy drink on metabolism and muscular performance. METHODS: Sixteen resistance-trained males (n = 8; mean ± SD; age: 22.4 ± 4.9 years; body mass: 78.8 ± 14.0 kg; body fat: 15.3 ± 6.4%) and females (n = 8; age: 24.5 ± 4.8 years; body mass: 67.5 ± 11.9 kg; body fat: 26.6 ± 7.1%) participated in this randomized, double-blind, placebo-controlled, crossover study. Following a familiarization visit, participants completed two identical visits to the laboratory separated by 5-10 days, each of which consisted of indirect calorimetry energy expenditure (EE) assessments before and after consumption of the beverage (Bang® Keto Coffee; 130 kcal, 300 mg caffeine, 20 g protein) or placebo (30 kcal, 11 mg caffeine, 1 g protein) as well as after exercise testing. In addition, participants' subjective feelings of energy, fatigue, and focus as well as muscular performance (leg press one-repetition maximum and repetitions to fatigue, maximal isometric and isokinetic squat testing) were assessed. Multiple repeated measures ANOVAs with Tukey post-hoc tests were used to analyze data. Estimates of effect size were quantified via partial eta squared (ηP2) and Hedge's g. RESULTS: A significant interaction effect was identified for EE (p < 0.001, ηP2 = 0.52) but not respiratory exchange ratio (p = 0.17, ηP2 = 0.11). Following consumption of the beverage, EE was 0.18 [corrected] kcal·min- 1 greater than placebo at the post-beverage time point (p < 0.001) and 0.08 [corrected] kcal·min- 1 greater than placebo at the post-exercise time point (p = 0.011). However, no between-condition differences were detected for any subjective or muscular performance outcomes. CONCLUSIONS: The results of this study suggest that consumption of the energy drink had minimal effects on lower-body muscular performance and subjective factors in the context of a laboratory setting. However, the beverage was found to significantly increase energy expenditure compared to placebo immediately following ingestion as well as during the recovery period after an exercise bout, suggesting that active individuals may improve acute metabolic outcomes via consumption of a caffeine- and protein-containing energy drink. TRIAL REGISTRATION: This trial was prospectively registered at ClinicalTrials.gov (Identifier: NCT04180787 ; Registered 29 November 2019).


Asunto(s)
Café , Bebidas Energéticas , Metabolismo Energético/fisiología , Ejercicio Físico/fisiología , Músculo Esquelético/fisiología , Entrenamiento de Fuerza , Adolescente , Adulto , Cafeína/farmacología , Calorimetría Indirecta , Estudios Cruzados , Método Doble Ciego , Metabolismo Energético/efectos de los fármacos , Prueba de Esfuerzo/métodos , Femenino , Humanos , Pierna/fisiología , Masculino , Músculo Esquelético/efectos de los fármacos , Sustancias para Mejorar el Rendimiento/farmacología , Intercambio Gaseoso Pulmonar/efectos de los fármacos , Entrenamiento de Fuerza/métodos , Levantamiento de Peso/fisiología , Adulto Joven
5.
J Cosmet Dermatol ; 18(4): 1037-1043, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30456780

RESUMEN

BACKGROUND AND OBJECTIVE: Topical aminophylline, caffeine, yohimbe, l-carnitine, and gotu kola (Centella asiatica) may aid in reducing body fat. Lipoxyderm™ contains these ingredients and was used to test if fat loss of the thigh, in conjunction with a low intensity exercise program and restricted calorie intake, was enhanced via the topical application of this lotion. METHODS: This was a double-blind, placebo-controlled, within-group study that investigated the effects of Lipoxyderm™ on thigh fat mass, circumference, and skinfold thickness. Seven participants underwent pre/post-exercise testing for weight, bilateral thigh circumference/skinfold thickness, and body composition/thigh fat mass assessment via dual-energy X-ray absorptiometry. Participants followed a hypocaloric diet, walked 150 minutes/wk, and were randomly assigned to apply a placebo to one leg and Lipoxyderm™ to their other leg for 28 days. Separate two-way mixed factorial repeated measures ANOVAs were used to compare the effects of Lipoxyderm™ to the placebo on thigh circumference, skinfold thickness, and fat mass. RESULTS: A significant time x group interaction was found for thigh circumference (F1,6  = 18.2, P = 0.005), skinfold thickness (F1,6  = 14.6, P = 0.009), and fat mass (F1,6  = 37.1, P = 0.001). CONCLUSIONS: A twice-daily topical application of Lipoxyderm™ for 28 days compared to a placebo combined with a walking program and a restricted caloric intake is more effective at reducing thigh circumference (1.2 vs 0.8 cm), thigh skinfold thickness (3.7 vs 2.0 mm), and thigh fat mass (100.0 g vs 57.3 g).


Asunto(s)
Dieta Reductora , Obesidad/prevención & control , Conducta Sedentaria , Crema para la Piel/administración & dosificación , Caminata , Adiposidad/efectos de los fármacos , Administración Cutánea , Adolescente , Adulto , Aminofilina/administración & dosificación , Cafeína/administración & dosificación , Carnitina/administración & dosificación , Centella/química , Terapia Combinada/métodos , Método Doble Ciego , Femenino , Humanos , Obesidad/etiología , Pausinystalia/química , Placebos/administración & dosificación , Extractos Vegetales/administración & dosificación , Crema para la Piel/química , Grosor de los Pliegues Cutáneos , Muslo , Resultado del Tratamiento , Adulto Joven
6.
J Int Soc Sports Nutr ; 13: 24, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27274715

RESUMEN

BACKGROUND: Phosphatidic acid (PA) is a lipid messenger that has been shown to increase muscle protein synthesis via signaling stimulation of the mammalian target of rapamycin (mTOR). MaxxTOR® (MT) is a supplement that contains PA as the main active ingredient but also contains other synergistic mTOR signaling substances including L-Leucine, Beta-Hydroxy-Beta-Methylbutyrate (HMB), and Vitamin D3. METHODS: Eighteen healthy strength-trained males were randomly assigned to a group that either consumed MT (n = 8, 22.0 +/- 2.5 years; 175.8 +/- 11.5 cm; 80.3 +/- 15.1 kg) or a placebo (PLA) (n = 10, 25.6 +/- 4.2 years; 174.8 +/- 9.0 cm; 88.6 +/- 16.6 kg) as part of a double-blind, placebo controlled pre/post experimental design. All participants volunteered to complete the three day per week resistance training protocol for the eight week study duration. To determine the effects of MT, participants were tested on one repetition maximum (1RM) leg press strength (LP), 1RM bench press strength (BP), push-ups to failure (PU), vertical jump (VJ), pro-agility shuttle time (AG), peak power output (P), lean body mass (LBM), fat mass (FM), and thigh muscle mass (TMM). Subjects were placed and monitored on an isocaloric diet consisting of 25 protein, 50 carbohydrates, and 25 % fat by a registered dietitian. Separate two-way mixed factorial repeated measures ANOVA's (time [Pre, Post] x group [MT and PLA] were used to investigate strength, body composition, and other performance changes. Post-hoc tests were applied as appropriate. Analysis were performed via SPSS with significance at (p ≤ 0.05). RESULTS: There was a significant main effect (F(1,16) = 33.30, p < 0.001) for LBM where MT significantly increased LBM when compared to the PLA group (p < 0.001). Additionally, there was a significant main effect for LP (F(1,16) = 666.74, p < 0.001) and BP (F(1,16) = 126.36, p < 0.001) where both increased significantly more in MT than PLA group (p < 0.001). No significant differences between MT and PLA were noted for FM, TMM, VJ, AG, P, or PU. CONCLUSION: The results of this eight week trial suggest that the addition of MaxxTOR® to a 3-day per week resistance training program can positively impact LBM and strength beyond the results found with exercise alone.


Asunto(s)
Umbral Anaerobio/efectos de los fármacos , Composición Corporal/efectos de los fármacos , Suplementos Dietéticos , Fuerza Muscular/efectos de los fármacos , Ácidos Fosfatidicos/farmacología , Resistencia Física/efectos de los fármacos , Entrenamiento de Fuerza , Adulto , Umbral Anaerobio/fisiología , Composición Corporal/fisiología , Método Doble Ciego , Alimentos Formulados , Humanos , Masculino , Fuerza Muscular/fisiología , Músculo Esquelético/fisiología , Fenómenos Fisiológicos en la Nutrición Deportiva , Serina-Treonina Quinasas TOR/metabolismo , Resultado del Tratamiento , Levantamiento de Peso
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