RESUMEN
To determine the underlying mechanisms after 1 session of (intense) whole-body electromyostimulation (WB-EMS) on total energy expenditure (TEE) and resting metabolic rate (RMR), 16 subjects followed a standardized protocol of indirect calorimetry for up to 72 h in 12-h intervals. The single session significantly increased RMR by approximately 25% ± 10% (p < 0.001) and TEE by approximately 9.5% ± 1%, a net effect of â¼460 ± 50 kcal (WB-EMS vs. control group).
Asunto(s)
Composición Corporal , Estimulación Eléctrica , Metabolismo Energético , Metabolismo de los Lípidos , Adulto , Metabolismo Basal , Índice de Masa Corporal , Peso Corporal , Calorimetría Indirecta , Estudios Cruzados , Femenino , Humanos , Masculino , Persona de Mediana Edad , Músculo Esquelético/fisiología , Adulto JovenRESUMEN
The purpose of this study was to determine the effect of below-knee compression stockings on running performance in men runners. Using a within-group study design, 21 moderately trained athletes (39.3 +/- 10.9 years) without lower-leg abnormities were randomly assigned to perform a stepwise treadmill test up to a voluntary maximum with and without below-knee compressive stockings. The second treadmill test was completed within 10 days of recovery. Maximum running performance was determined by time under load (minutes), work (kJ), and aerobic capacity (ml.kg.min). Velocity (kmxh) and time under load were assessed at different metabolic thresholds using the Dickhuth et al. lactate threshold model. Time under load (36.44 vs. 35.03 minutes, effect size [ES]: 0.40) and total work (422 vs. 399 kJ, ES: 0.30) were significantly higher with compression stockings compared with running socks. However, only slight, nonsignificant differences were observed for VO2max (53.3 vs. 52.2 mlxkgxmin, ES: 0.18). Running performance at the anaerobic (minimum lactate + 1.5 mmolxL) threshold (14.11 vs. 13.90 kmxh, ES: 0.22) and aerobic (minimum lactate + 0.5 mmolxL) thresholds (13.02 vs. 12.74 kmxh, ES: 0.28) was significantly higher using compression stockings. Therefore, stockings with constant compression in the area of the calf muscle significantly improved running performance at different metabolic thresholds. However, the underlying mechanism was only partially explained by a slightly higher aerobic capacity.
Asunto(s)
Umbral Anaerobio/fisiología , Rendimiento Atlético , Resistencia Física/fisiología , Carrera/fisiología , Medias de Compresión , Análisis de Varianza , Antropometría , Estudios Cruzados , Prueba de Esfuerzo/métodos , Humanos , Masculino , Probabilidad , Valores de Referencia , Adulto JovenRESUMEN
The purpose of this study was to present an equation that accurately predicts 1 repetition maximum (RM) over a wide range of repetitions to fatigue (RTF) for 4 different machine resistance exercises in postmenopausal women. Seventy trained women (age = 57.4 +/- 3.1 years) performed maximal and submaximal repetitions on leg press, bench press, rowing, and leg adduction machines at the conclusion of a 2-year training program. Maximal repetitions were performed on each exercise in the following ranges: 3-5RM, 6-10RM, 11-15RM, and 16-20RM. Special regard was taken to maintain the identical execution of each test (i.e., range of motion, starting angle, speed of movement). One cubic polynomial (w(i) [0.988-0.0000584 r(i)(3) + 0.00190 r(i)(2) + 0.0104 r(i),] where w(i) is the load of measurement I, and r(i) is the number of repetitions) accurately predicted 1RM from RTF with mean absolute differences between actual 1RM and predicted 1RM for the 4 exercises of 1.5-3.1% and with coefficients of variation of <3.3%. Equation accuracy was independent of the exercise type or the number of RTF. Thus, this study supported the validity of RTF to adequately estimate 1RM over a wide range of repetitions and within different exercises in trained, older female subjects.