RESUMEN
Foam rolling (FR) has recently become very popular among athletes and recreational exercisers and is often used during warm up prior to strength training (ST) to induce self-myofascial release. The purpose was to examine the acute effects of ST and FR performed in isolation or in combination on blood pressure (BP) responses during recovery in normotensive women. Sixteen normotensive and strength trained women completed four interventions: 1) rest control (CON), 2) ST only, 3) FR only, and 4) ST immediately followed by FR (ST + FR). ST consisted of three sets of bench press, back squat, front pull-down, and leg press exercises at 80% of 10RM. FR was applied unilaterally in two sets of 120 s to each of the quadriceps, hamstring, and calf regions. Systolic (SBP) and diastolic (DBP) BP were measured before (rest) and every 10 min, for 60 min, following (Post 10-60) each intervention. Cohen's d effect sizes were calculated to indicate the magnitude effect by the formula d = Md/Sd, where Md is the mean difference and Sd is the standard deviation of differences. Cohen's d effect-sizes were defined as small (≥0.2), medium (≥0.5), and large (≥0.8). There were significant reductions in SBP for ST at Post-50 (p < 0.001; d = -2.14) and Post-60 (p < 0.001; d = -4.43), for FR at Post-60 (p = 0.020; d = -2.14), and for ST + FR at Post-50 (p = 0.001; d = -2.03) and Post-60 (p < 0.001; d = -2.38). No change in DBP was observed. The current findings suggest that ST and FR performed in isolation can acutely reduce SBP but without an additive effect. Thus, ST and FR can both be used to acutely reduce SBP and, importantly, FR can be added to a ST regimen without furthering the SBP reduction during recovery.
Asunto(s)
Hipotensión Posejercicio , Entrenamiento de Fuerza , Humanos , Femenino , Presión Sanguínea/fisiología , Estudios Cruzados , Músculo Cuádriceps/fisiologíaRESUMEN
Increases in joint range-of-motion may be beneficial for improving performance and reducing injury risk. This study investigated the effects of different self-massage volumes and modalities on passive hip range-of-motion. Twenty-five recreationally resistance-trained men performed four experimental protocols using a counterbalanced, randomized, and within-subjects design; foam rolling (FR) or roller massage (RM) for 60 or 120-s. Passive hip flexion and extension range-of-motion were measured in a counterbalanced and randomized order via manual goniometry before self-massage (baseline) and immediately, 10-, 20-, and 30-min following each self-massage intervention. Following FR or RM of quadriceps, there was an increase in hip flexion range-of-motion at Post-0 (FR: Δâ¯=â¯19.28°; RM: Δâ¯=â¯14.96°), Post-10 (FR: Δâ¯=â¯13.03°; RM: Δâ¯=â¯10.40°), and Post-20 (FR: Δâ¯=â¯6.00°; RM: Δâ¯=â¯4.64°) for all protocols, but these did not exceed the minimum detectable change at Post-10 for RM60 and RM120, and Post-20 for FR60, FR120, RM60, and RM120. Similarly, hip extension range-of-motion increased at Post-0 (FR: Δâ¯=â¯8.56°; RM: Δâ¯=â¯6.56°), Post-10 (FR: Δâ¯=â¯4.64°; RM: Δâ¯=â¯3.92°), and Post-20 (FR: Δâ¯=â¯2.80°; RM: Δâ¯=â¯1.92°), but did not exceed the minimum detectable change at Post-10 for FR60, RM60, and RM120, and Post-20 for FR60, FR120, RM60, and RM120. In conclusion, both FR and RM increased hip range-of-motion but larger volumes (120- vs. 60-second) and FR produced the greatest increases. These findings have implications for self-massage prescription and implementation, in both rehabilitation and athletic populations.
Asunto(s)
Articulación de la Cadera/fisiología , Masaje/métodos , Músculo Cuádriceps/fisiología , Rango del Movimiento Articular/fisiología , Adulto , Humanos , Masculino , Método Simple Ciego , Adulto JovenRESUMEN
CONTEXT: Cold-water immersion is the criterion standard for treatment of exertional heat illness. Cryotherapy and water immersion also have been explored as ergogenic or recovery aids. The kinetics of inflammatory markers, such as interleukin-6 (IL-6), during cold-water immersion have not been characterized. OBJECTIVE: To characterize serum IL-6 responses to water immersion at 2 temperatures and, therefore, to initiate further research into the multidimensional benefits of immersion and the evidence-based selection of specific, optimal immersion conditions by athletic trainers. DESIGN: Controlled laboratory study. SETTING: Human performance laboratory Patients or Other Participants: Eight college-aged men (age = 22 ± 3 years, height = 1.76 ± 0.08 m, mass = 77.14 ± 9.77 kg, body fat = 10% ± 3%, and maximal oxygen consumption = 50.48 ± 4.75 mL·kg(-1) min(-1)). MAIN OUTCOME MEASURES: Participants were assigned randomly to receive either cold (11.70°C ± 2.02°C, n = 4) or warm (23.50°C ± 1.00°C, n = 4) water-bath conditions after exercise in the heat (temperature = 37°C, relative humidity = 52%) for 90 minutes or until volitional cessation. RESULTS: Whole-body cooling rates were greater in the cold water-bath condition for the first 6 minutes of water immersion, but during the 90-minute, postexercise recovery, participants in the warm and cold water-bath conditions experienced similar overall whole-body cooling. Heart rate responses were similar for both groups. Participants in the cold water-bath condition experienced an overall slight increase (30.54% ± 77.37%) in IL-6 concentration, and participants in the warm water-bath condition experienced an overall decrease (-69.76% ± 15.23%). CONCLUSIONS: We have provided seed evidence that cold-water immersion is related to subtle IL-6 increases from postexercise values and that warmer water-bath temperatures might dampen this increase. Further research will elucidate any anti-inflammatory benefit associated with water-immersion treatment and possible multidimensional uses of cooling therapies.
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Trastornos de Estrés por Calor/terapia , Hidroterapia , Hipertermia Inducida , Hipotermia Inducida , Interleucina-6/sangre , Temperatura Corporal/fisiología , Regulación de la Temperatura Corporal/fisiología , Frío , Crioterapia , Ejercicio Físico , Frecuencia Cardíaca , Humanos , Inmersión , Masculino , Agua , Adulto JovenRESUMEN
INTRODUCTION: Previous research has demonstrated that ingestion of essential amino acids and their metabolites induce anabolic effects with the potential to augment gains in lean body mass and strength after resistance exercise training. PURPOSE: The purpose of the present study was to examine the effects of an essential amino acid-based formula (Muscle Armor (MA); Abbott Laboratories, Abbott Park, IL) containing beta-hydroxy-beta-methylbutyrate (HMB) on hormonal and muscle damage markers in response to 12 wk of resistance exercise. METHODS: Seventeen healthy men (mean body mass: 77.9 +/- 7.2 kg; mean height: 174.3 +/- 12.4 cm; mean age: 22.9 +/- 3.8 yr) were matched and randomized into two groups and performed 12 wk of periodized heavy resistance training while supplementing with either MA or an isocaloric, isonitrogenous placebo (CON). Every 2 wk during the 12-wk intervention, resting blood draws were obtained, and muscle strength and power were measured. In addition, blood draws were obtained before, during, and after a standardized resistance exercise challenge performed pre-, mid-, and posttraining. RESULTS: Lean body mass, muscle strength, and muscle power significantly (P Asunto(s)
Adaptación Fisiológica/efectos de los fármacos
, Aminoácidos/metabolismo
, Suplementos Dietéticos
, Entrenamiento de Fuerza
, Adulto
, Aminoácidos/administración & dosificación
, Método Doble Ciego
, Humanos
, Masculino
, Fuerza Muscular/efectos de los fármacos
, Fuerza Muscular/fisiología
, Adulto Joven
RESUMEN
The influence of a proprietary blend of modified cellulose and cetylated fatty acids (Trisynextrade mark, Imagenetix, Inc., San Diego, CA 92127, USA) on adipocytokine and regional body composition responses to a weight loss program was examined. Twenty-two women (Supplement group (S) (n = 11): age = 36.8 +/- 7.2 years; weight = 87.1 +/- 6.2 kg; % body fat = 43.4 +/- 4.1; Placebo group (P) (n = 11): age = 38.3 +/- 6.8 years; weight = 86.9 +/- 4.7 kg; % body fat = 44.3 +/- 2.0) completed an 8-week placebo-controlled, double-blind study consisting of a caloric restricted diet and cardiovascular exercise. Body composition and serum insulin, leptin, and adiponectin were assessed at pre-, mid-, and post-intervention. From pre- to post-intervention, significant decreases (P < 0.05) were observed for body weight (S: 87.1 +/- 6.2-77.9 +/- 5.1 kg; P: 86.9 +/- 4.7-82.7 +/- 3.8 kg) (P < 0.05 S vs. P), % body fat (S: 43.4 +/- 4.1-36.1 +/- 3.6; P: 44.3 +/- 2.0-40.6 +/- 1.2) (P < 0.05 S vs. P), leptin (S: 28.3 +/- 3.5-16.2 +/- 2.6 ng ml(-1); P: 29.4 +/- 3.2-19.9 +/- 1.1 ng ml(-1)) (P < 0.05 S vs. P), and insulin (S: 7.3 +/- 0.8-5.1 +/- 0.2 mU l(-1); P: 7.7 +/- 0.9-5.1 +/- 0.3 mU l(-1)). Serum adiponectin increased (P < 0.05) (S: 12.2 +/- 2.4-26.3 +/- 3.0 microg ml(-1): 12.6 +/- 2.0-21.8 +/- 3.1 microg ml(-1)) (P < 0.05 for S vs. P). Supplementation with a proprietary blend of modified cellulose and cetylated fatty acids during an 8-week weight loss program exhibited favorable effects on adipocytokines and regional body composition.
Asunto(s)
Adipoquinas/sangre , Adiposidad/fisiología , Celulosa/uso terapéutico , Suplementos Dietéticos , Terapia por Ejercicio , Ácidos Grasos/uso terapéutico , Sobrepeso/terapia , Adulto , Composición Corporal/fisiología , Terapia Combinada , Método Doble Ciego , Femenino , Humanos , Obesidad/terapia , Sobrepeso/sangre , Sobrepeso/dietoterapiaRESUMEN
Because carnitine has been shown to decrease oxidative stress and improve endothelial cell functioning, we examined the effects of carnitine supplementation on postprandial flow-mediated dilation (FMD) and circulating biomarkers of inflammation and oxidative stress after a high-fat meal. A randomized, double-blind, placebo-controlled, crossover study design was used. Thirty men and women (age 30 +/- 8 year, body mass 72.9 +/- 17.1 kg, body fat 13.0 +/- 6.4%) participated in 2 vascular testing days, each preceded by 3 weeks of supplementation with either 2 g/day of L-Carnitine (L-Carnitine L-Tartrate) or placebo with a 3- to 5-week washout period between trials. Brachial artery FMD in response to 5 minutes of upper arm occlusion and circulating markers of oxidative stress and inflammation were measured in the fasting state and after a standardized high-fat meal. After 3 weeks of supplementation, peak FMD in the fasting state was similar between the carnitine and placebo trials, averaging 6.6%. Peak FMD during the postprandial period decreased to 5.8% at 1.5 hours during placebo and increased to 7.7% during the carnitine trial (n = 30: p = 0.043 for supplement by time interaction effect). This improvement in postprandial vascular function was most dramatic in subjects who showed a decrease in peak FMD in response to the meal (n = 15: p = 0.003 for supplement by time interaction effect). There was a significant increase in postprandial lipemia and plasma interleukin-6 but no effect of supplementation. There were no significant postprandial changes or supplement effects for plasma tumor necrosis factor-alpha and malondialdehyde. In conclusion, consistent with other work showing a beneficial effect of carnitine on vascular function, these findings indicate that carnitine supplementation in healthy individuals improves postprandial FMD after a high-fat meal.
Asunto(s)
Vasos Sanguíneos/inmunología , Carnitina/administración & dosificación , Grasas de la Dieta , Suplementos Dietéticos , Alimentos , Interleucina-6/sangre , Vasodilatación , Adulto , Estudios Cruzados , Método Doble Ciego , Femenino , Humanos , Inflamación , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
Previous research has shown that L-carnitine L-tartrate (LCLT) supplementation beneficially affects markers of hypoxic stress following resistance exercise. However, the mechanism of this response is unclear. Therefore, the primary purpose of this study was to determine the effects of LCLT supplementation on muscle tissue oxygenation during and after multiple sets of squat exercise. Nine healthy, previously resistance-trained men (25.2 +/- 6.years, 91.2 +/- 10.2 kg, 180.2 +/- 6.3 cm) ingested 2 g.d of LCLT or an identical placebo for 23 days in a randomized, balanced, crossover, double-blind, placebo-controlled, repeated-measures study design. On day 21, forearm muscle oxygenation was measured during and after an upper arm occlusion protocol using near infrared spectroscopy (NIRS), which measures the balance of oxygen delivery in relation to oxygen consumption. On day 22, subjects performed 5 sets of 15 to 20 repetitions of squat exercise with corresponding measures of thigh muscle oxygenation, via NIRS, and serial blood draws. Compared to the placebo trial, muscle oxygenation was reduced in the LCLT trial during upper arm occlusion and following each set of resistance exercise. Despite reduced oxygenation, plasma malondealdehyde, a marker of membrane damage, was attenuated during the LCLT trial. There were no differences between trials in the vasoactive substance prostacyclin. In conclusion, because oxygen delivery was occluded during the forearm protocol, it is proposed that enhanced oxygen consumption mediated the reduced muscle oxygenation during the LCLT trial. Enhanced oxygen consumption would explain why hypoxic stress was attenuated with LCLT supplementation.
Asunto(s)
Carnitina/administración & dosificación , Ejercicio Físico , Músculo Esquelético/metabolismo , Oxígeno/metabolismo , Tartratos/administración & dosificación , Complejo Vitamínico B/administración & dosificación , Adulto , Estudios Cruzados , Suplementos Dietéticos , Método Doble Ciego , Humanos , Masculino , Malondialdehído/sangre , Consumo de Oxígeno , Espectroscopía Infrarroja CortaRESUMEN
Muscle power and strength decrease with age leading to reduced independence and increased health risk from falls. Creatine supplementation can increase muscle power and strength. The purpose of this study was to examine the effects of 7 days of creatine supplementation on body composition, muscular strength, and lower-body motor functional performance in older women. Thirty 58-71 year old women performed three test sessions (T1-T3) each separated by one week. Each session consisted of one repetition maximum tests for bench press and leg press, and isometric hand-grip, tandem gait, upper-body ergometer, and lower-body ergometer tests. Following T2, subjects were assigned to a creatine monohydrate (0.3 g kg body mass(-1) for 7 days) (CR: 63.31 +/- 1.22 year, 160.00 +/- 1.58 cm, 67.11 +/- 4.38 kg) or a placebo (PL: 62.98 +/- 1.11 year, 162.25 +/- 2.09 cm, 67.84 +/- 3.90 kg) supplementation group. CR significantly (P < 0.05) increased bench press (1.7 +/- 0.4 kg), leg press (5.2 +/- 1.8 kg), body mass (0.49 +/- 0.04 kg) and fat free mass (0.52 +/- 0.05) and decreased completion time on the functional tandem gait tests from T2-T3. No significant changes were found for PL on any of the measured variables. No adverse side-effects were reported by either group. Short-term creatine supplementation resulted in an increase in strength, power, and lower-body motor functional performance in older women without any adverse side effects.
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Creatina/administración & dosificación , Suplementos Dietéticos , Contracción Muscular/fisiología , Músculo Esquelético/fisiología , Esfuerzo Físico/fisiología , Análisis y Desempeño de Tareas , Administración Oral , Factores de Edad , Femenino , Humanos , Persona de Mediana Edad , Contracción Muscular/efectos de los fármacos , Músculo Esquelético/efectos de los fármacos , Esfuerzo Físico/efectos de los fármacosRESUMEN
The purpose of this study was to determine the influence of a comprehensive multi-component nutritional supplement on performance, hormonal, and metabolic responses to an acute bout of resistance exercise. Nine healthy subjects ingested either Muscle Fuel (MF) or a matched placebo (PL) for 7 days. Subjects then reported to the laboratory, ingested the corresponding supplement, and performed two consecutive days of heavy resistance exercise testing with associated blood draws. MF supplementation improved vertical jump (VJ) power output and the number of repetitions performed at 80% of one repetition maximum (1RM). Additionally, MF supplementation potentiated growth hormone (GH), testosterone, and insulin-like growth factor-1 responses to exercise. Concentrations of circulating myoglobin and creatine kinase (CK) were attenuated immediately following resistance exercise during the MF trial, indicating that MF partially mediated some form of exercise-induced muscle tissue damage. In summary MF enhanced performance and hormonal responses associated with an acute bout of resistance exercise. These responses indicate that MF supplementation augments the quality of an acute bout of resistance exercise thereby increasing the endocrine signaling and recovery following heavy resistance exercise.
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Suplementos Dietéticos , Ejercicio Físico/fisiología , Hormonas/sangre , Adulto , Aminoácidos/sangre , Biomarcadores/sangre , Glucemia/metabolismo , Composición Corporal/fisiología , Creatina Quinasa/metabolismo , Estudios Cruzados , Dieta , Método Doble Ciego , Frecuencia Cardíaca/fisiología , Hormona de Crecimiento Humana/sangre , Humanos , Insulina/sangre , Factor I del Crecimiento Similar a la Insulina/metabolismo , Ácido Láctico/sangre , Masculino , Actividad Motora/fisiología , Fatiga Muscular/fisiología , Fuerza Muscular/fisiología , Mioglobina/metabolismo , Testosterona/sangreRESUMEN
L-carnitine L-tartrate (LCLT) supplementation beneficially affects markers of postexercise metabolic stress and muscle damage. However, to date, no study has determined the dose response of LCLT to elicit such responses. Therefore, the purpose of this study was to determine the effects of different doses of LCLT on criterion variables previously shown to be responsive to LCLT supplementation. Eight healthy men (22 +/- 3 y, 174 +/- 5 cm, 83.0 +/- 15.3 kg) were supplemented with 0 g, 1 g, and 2 g of LCLT for 3 weeks and then performed a bout of resistance exercise (5 sets of 15-20 repetition maximum with a 2-min rest between sets) with associated blood draws. This procedure was performed in a balanced, randomized, repeated measures design. Serum carnitine concentrations increased (p < or = 0.05) following the 1 g and 2 g doses, with the 2-g dose providing the highest carnitine concentrations. The 1- and 2-g doses reduced postexercise serum hypoxanthine, serum xanthine oxidase, serum myoglobin, and perceived muscle soreness. In conclusion, both the 1- and 2-g doses were effective in mediating various markers of metabolic stress and of muscle soreness. Use of LCLT appears to attenuate metabolic stress and the hypoxic chain of events leading to muscle damage after exercise.
Asunto(s)
Biomarcadores/sangre , Carnitina/farmacología , Suplementos Dietéticos , Tartratos/farmacología , Adulto , Análisis de Varianza , Área Bajo la Curva , Glucemia/análisis , Carnitina/sangre , Estudios Cruzados , Relación Dosis-Respuesta a Droga , Prueba de Esfuerzo , Fuerza de la Mano , Humanos , Hipoxantina/sangre , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/sangre , Lactatos/sangre , Masculino , Mioglobina/sangre , Dolor/fisiopatología , Educación y Entrenamiento Físico , Tartratos/sangre , Xantina Oxidasa/sangreRESUMEN
PURPOSE: Chromium enhances insulin signaling and insulin-mediated glucose uptake in cultured cells. We investigated the effect of chromium on glycogen synthesis and insulin signaling in humans. METHODS: Sixteen overweight men (BMI = 31.1 +/- 3.0 kg.m) were randomly assigned to supplement with 600 microg.d chromium as picolinate (Cr; N = 8) or a placebo (Pl; N = 8). After 4 wk of supplementation, subjects performed a supramaximal bout of cycling exercise to deplete muscle glycogen, which was followed by high-glycemic carbohydrate feedings for the next 24 h. Muscle biopsies were obtained at rest, immediately after exercise, and 2 and 24 h after exercise. RESULTS: Elevations in glucose and insulin during recovery were not different, but the lactate response was significantly higher in Cr. There was a significant depletion in glycogen immediately after exercise, an increase at 2 h, and a further increase above rest at 24 h (P < 0.05). The rate of glycogen synthesis during the 2 h after exercise was not different between groups (Cr: 25.8 +/- 8.0 and Pl: 17.1 +/- 4.7 mmol.kg.h). Glycogen synthase activity was significantly increased immediately after exercise in both groups. Muscle phosphatidylinositol 3-kinase (PI 3-kinase) activity decreased immediately after exercise and increased at 2 h (P < 0.05), with a trend for a lower PI 3-kinase response in Cr (P = 0.08). CONCLUSIONS: Chromium supplementation did not augment glycogen synthesis during recovery from high-intensity exercise and high-carbohydrate feeding, although there was a trend for lower PI 3-kinase activity.
Asunto(s)
Suplementos Dietéticos , Prueba de Esfuerzo , Glucógeno/biosíntesis , Quelantes del Hierro/farmacología , Resistencia Física , Ácidos Picolínicos/farmacología , Adulto , Biopsia con Aguja , Dieta Baja en Carbohidratos , Método Doble Ciego , Humanos , Ácido Láctico/sangre , Masculino , Músculo Esquelético/metabolismo , Músculo Esquelético/patología , Sobrepeso , Fosfatidilinositol 3-Quinasas/metabolismo , Factores de TiempoRESUMEN
PURPOSE: The purpose of this investigation was to determine the effects of 3 wk of L-carnitine L-tartrate (LCLT) supplementation and post-resistance-exercise (RE) feeding on hormonal and androgen receptor (AR) responses. METHODS: Ten resistance-trained men (mean+/-SD: age, 22+/-1 yr; mass, 86.3+/-15.3 kg; height, 181+/-11 cm) supplemented with LCLT (equivalent to 2 g of L-carnitine per day) or placebo (PL) for 21 d, provided muscle biopsies for AR determinations, then performed two RE protocols: one followed by water intake, and one followed by feeding (8 kcal.kg body mass, consisting of 56% carbohydrate, 16% protein, and 28% fat). RE protocols were randomized and included serial blood draws and a 1-h post-RE biopsy. After a 7-d washout period, subjects crossed over, and all experimental procedures were repeated. RESULTS: LCLT supplementation upregulated (P<0.05) preexercise AR content compared with PL (12.9+/-5.9 vs 11.2+/-4.0 au, respectively). RE increased (P<0.05) AR content compared with pre-RE values in the PL trial only. Post-RE feeding significantly increased AR content compared with baseline and water trials for both LCLT and PL. Serum total testosterone concentrations were suppressed (P<0.05) during feeding trials with respect to corresponding water and pre-RE values. Luteinizing hormone demonstrated subtle, yet significant changes in response to feeding and LCLT. CONCLUSION: In summary, these data demonstrated that: 1) feeding after RE increased AR content, which may result in increased testosterone uptake, and thus enhanced luteinizing hormone secretion via feedback mechanisms; and 2) LCLT supplementation upregulated AR content, which may promote recovery from RE.