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AIM: Both an acute bout of resistance exercise (RE) and caffeine consumption can significantly alter hemodynamics, autonomic modulation, and arterial stiffness, which may correlate with adverse cardiovascular events. However, effects of an acute bout of RE and caffeine are unclear in resistance-trained women. PURPOSE: The purpose of this study was to compare the effects of an acute bout of RE with repetitions to failure on squat and bench press, with or without caffeine, on performance, resting and recovery measures of hemodynamics, autonomic modulation, as well as arterial stiffness in resistance-trained women. METHODS: Eleven women participated in a double-blind, placebo controlled cross-over design in which they consumed caffeine (4 mg/kg) or placebo at least 72 h apart. Sixty minutes following ingestion, participants performed two sets of 10 repetitions followed by a third set to failure on squat and bench press. Hemodynamics, autonomic modulation, and arterial stiffness were measured at rest, 60 min post-ingestion, and three minutes and 10 min following RE. RESULTS: Data demonstrated caffeine has no additive effects on performance, hemodynamics, autonomic modulation, or arterial stiffness (p > 0.05) before or following an acute bout of RE in resistance-trained women compared to a placebo. CONCLUSIONS: Resistance-trained women may not observe any alteration to RE performance on the squat and bench press in terms of repetitions to failure following caffeine ingestion. In addition, the data from the present study suggests that there may also not be any further negative effects on the cardiovasculature if caffeine is consumed prior to the RE bout.
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Entrenamiento de Fuerza , Rigidez Vascular , Humanos , Femenino , Cafeína/farmacología , Resistencia Física , Hemodinámica , Estudios Cruzados , Método Doble CiegoRESUMEN
INTRODUCTION: Blood flow restriction (BFR) exercise has emerged as a method of increasing muscle size and strength with low intensity resistance training. While the cuff pressures used during BFR are typically a percentage of resting arterial occlusion pressure (AOP), the impact these cuff pressures have on blood flow during lower body exercise is unknown. PURPOSE: To determine how various cuff pressures impact blood flow and tissue perfusion during exercise. METHODS: Eleven healthy male participants completed four sets of knee extension (30 reps per set at 30% max torque) with 0%, 60%, 80%, and 100% of arterial occlusion pressure (AOP) was applied to the proximal portion of the thigh. Femoral artery blood flow, tissue oxygenation, and central hemodynamics were continuously recorded before, during, and after exercise. Electromyography (EMG) amplitude was recorded from the vastus lateralis during exercise. RESULTS: Blood flow increased during exercise compared to rest across all cuff pressures (p < 0.001), however compared to 0%, the absolute blood flow was reduced by 34 ± 17%, 45 ± 22%, and 72 ± 19% for 60, 80, and 100% AOP, respectively. Furthermore, each cuff pressure resulted in similar relative changes in blood flow before, during, and after exercise. During exercise, tissue saturation index (TSI) decreased as cuff pressure increased (p ≤ 0.005) with the exception of 80 to 100% AOP. Deoxyhemoglobin increased (p ≤ 0.001) with cuff pressure. CONCLUSION: Our data indicate that while BFR knee extension elicits an absolute hyperemic response at cuff pressures up to 100% resting AOP, the relative reductions in blood flow are consistent across rest, exercise and recovery.
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Hemodinámica , Precondicionamiento Isquémico/métodos , Rodilla/fisiología , Flujo Sanguíneo Regional , Entrenamiento de Fuerza/métodos , Adulto , Vendajes de Compresión/normas , Humanos , Precondicionamiento Isquémico/instrumentación , Rodilla/irrigación sanguínea , Masculino , Contracción Muscular , Músculo Esquelético/irrigación sanguínea , Músculo Esquelético/fisiología , Presión , Entrenamiento de Fuerza/instrumentaciónRESUMEN
BACKGROUND: Cannabis use, be it either cannabidiol (CBD) use and/or delta-9-tetrahydrocannabinol (THC) use, shows promise to enhance exercise recovery. The present study aimed to determine if individuals are using CBD and/or THC as a means of recovery from aerobic and/or resistance exercise, as well as additional modalities that might be used to aid in recovery. METHODS: Following consent, 111 participants (Mean ± SD: Age: 31 ± 13 years) completed an anonymous survey. All participants were regularly using cannabis (CBD and/or THC) as well as were currently exercising. Questions pertained to level of cannabis use, methods used for consumption of cannabis, exercise habits, exercise recovery strategies, and demographics. RESULTS: Eighty-five percent of participants reported participating in aerobic training. In addition, 85% of participants also reported regular participation in resistance exercise. Seventy-two percent of participants participated in both aerobic and resistance exercise. Ninety-three percent of participants felt that CBD use assisted them with recovery from exercise, while 87% of participants felt the same regarding THC use. CONCLUSIONS: Individuals who habitually use cannabis, CBD or THC, and regularly engage in exercise do feel that cannabis assists them with exercise recovery. More data are necessary to understand the role of cannabis in exercise recovery as well as perceived ergogenic benefits of cannabis by individuals who both regularly participate in exercise and habitually use cannabis.
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While it has been demonstrated that acute resistance exercise (RE) alters measures of wave reflection and aortic arterial stiffness in young, healthy individuals, limited research has evaluated sex differences. Accordingly, we recruited moderately active, resistance-trained men (Age: 22 ± 3yrs, n=12) and women (23 ± 3yrs, n=10) to perform two randomized conditions consisting of an acute bout of weight machine RE or a quiet control (CON). Measures of aortic wave reflection and aortic stiffness were taken at baseline and 15 minutes following the RE (Recovery). At baseline, women had significantly higher heart rate (p = 0.05) and lower brachial systolic blood pressure (p = 0.009) compared to men. There were no significant three-way interactions for any variable. Significant condition by time interactions were noted for heart rate (Baseline: 65 ± 10bpm, Recovery: 87 ± 13bpm, p = 0.001), brachial systolic blood pressure (Baseline: 116 ± 9mmHg, Recovery: 123 ± 10mmHg, p = 0.014), and the augmentation index (AIx) normalized at 75bpm (Baseline: 7.7 ± 12.8%, Recovery: 15.5 ± 9.5%, p = 0.002) such that Recovery was augmented compared to Baseline following RE but not CON. There was also a significant main effect of time for augmentation pressure (Baseline: 4.1 ± 4.0mmHg, Recovery: 4.0 ± 3.6mmHg, p = 0.04) such that it decreased from Baseline to Recovery following RE but not the CON. There were no significant effects of sex, condition, or time on aortic arterial stiffness. Men and women have similar responses in measures of aortic wave reflection and aortic arterial stiffness following acute RE using weight machines.
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Objective: This study assessed the oxygen consumption [VO2 mL/(kg·min)], liking, and relative reinforcing (motivating) value (RRV) of a moderately physiologically challenging exergame [Nintendo Wii-Sports Boxing (Boxing)] versus a minimally challenging exergame [Nintendo Wii Lego Star Wars (Lego)]. Materials and Methods: VO2 and liking were recorded in children(N = 28, 7.8 ± 1.3 years old) during three 10-minute conditions: recumbent resting (Resting), and playing Wii Boxing or Wii Lego. Resting was completed first, and the order of exergames was randomized. Next, children performed an operant button pressing task using a progressive fixed ratio to assess the RRV of the two videogame conditions. Children worked to earn up to 11 minutes for Boxing, Lego, or a combination of the two. The output maximum (Omax) performed to earn access to each game was the measure of RRV. Results: There was a significant (P ≤ 0.03 for all conditions) step-wise increase in VO2 from Resting [4.3 ± 1.2 mL/(kg·min)] to Lego [5.3 ± 0.5 mL/(kg·min)] and from Lego to Boxing [11.7 ± 4.2 mL/(kg·min)]. Liking was significantly greater for Boxing (P = 0.003) and Lego (P < 0.0001, 7.1 ± 2.9 cm; 7.1 ± 2.7 cm, respectively) versus Resting (4.6 ± 3.8 cm), with no significant difference between Boxing and Lego (P = 0.358). Lastly, Omax was significantly (P = 0.021) greater for Lego (257.7 ± 390.6 presses) than for Boxing (51.7 ± 131.0 presses). Conclusion: Oxygen consumption during Wii Boxing was significantly greater than during Wii Lego. Despite this greater physiological challenge, liking was similar for both Lego and Boxing. However, children were more motivated to play Lego than Boxing.