RESUMO
BACKGROUND: Several investigations suggest that high-intensity interval training (HIIT) provokes larger changes in VO2max compared to moderate-intensity continuous training (MICT); other studies associate HIIT with significant decreases in total, abdominal and visceral fat mass. However, some meta-analyses express that the enhancements with HIIT on VO2max are slightly higher concerning MICT. These studies had low-to-moderate methodological quality, and the exercise protocols were completed mostly on treadmills or cycle ergometers. Thus, the objective of this study was to compare the effect of a low-volume HIIT versus a MICT program on VO2max, body fat percentage (BFP), and health-related quality of life (HRQoL) in overweight women. It followed a research protocol with high methodological rigor and good reporting quality. METHODS: After two physical adaptation weeks (run-in period), thirty-five volunteers were randomized to HIIT (n = 16) or MICT (n = 19). Both groups performed 24 sessions on a grass sports field (walking, jogging or running). The HIIT group completed 15 bouts of 30 s [90-95%, maximal heart rate (HRmax)], while the MICT group completed 30 min of continuous exercise (65-75% HRmax). RESULTS: The difference between HIIT and MICT post-intervention on VO2max was not statistically significant (0.8 ml/kg/min. CI 95%, -1.0 to 2.7, p = 0.37). Similarly, no statistically significant differences were found between groups for BFP and HRQoL. CONCLUSIONS: Low-volume HIIT program has no quantitative advantage compared with that resulting from MICT, in VO2max, BFP, and HRQoL. ClinicalTrials.gov Identifier: NCT03300895.
RESUMO
Abstract Background: Although the benefits of exercise and changes in lifestyle on components of the metabolic syndrome (MS) have been described, little is known about the effect of dancing and nutritional changes on the cardiovascular system. Objective: Evaluate the effect of an intervention based on dancing and nutrition education on hemodynamic and autonomic status in adults with MS. Methods: A randomized controlled clinical trial was conducted involving 59 adults with MS. The intervention lasted 12 weeks and consisted of an aerobic exercise program (dancing) at an intensity of 60-75% of heart rate reserve, 60 minutes 3 times a week, and muscle strength training at an intensity of 50% of a maximum repetition, 30 minutes twice a week. The nutrition education program consisted of 2-hour workshops each week. Assessment of impedance cardiography and function of nervous system with analysis of heart rate variability (HRV) were made before and after the intervention. Results: In the intervention group, a decrease in mean arterial pressure of -7.8 mmHg (95% CI, -12.84 to -2.75; P = 0.004) was found as well as in the systemic vascular resistance (SVR) index of -864.29 dyn·s·m2/cm5 (95% CI, -1506.31 to -222.26; P = 0.010). Increase was observed in the cardiac output index of 0.48 L/min/m2 (95% CI, 0.14 to 0.83; P = 0.007). In the spectral analysis of HRV a reduction in LF/HF ratio of -0.52 (95% CI, -1.02 to -0.02; P = 0.040) was also found.
Resumen Antecedentes: Aunque se describieron los beneficios del ejercicio y cambios en el estilo de vida sobre los componentes del síndrome metabólico (SM), poco se sabe del efecto del baile y la nutrición en el sistema cardiovascular. Objetivo: Evaluar el efecto de una intervención de baile y educación nutricional sobre el estado hemodinámico y autonómico en adultos con SM. Materiales y métodos: Ensayo clínico controlado que incluyó 59 adultos con SM. La intervención duró 12 semanas y consistió en un programa de baile a una intensidad del 60 a 75% de la frecuencia cardiaca de reserva, 60 minutos, 3 veces a la semana, y entrenamiento de la fuerza a una intensidad del 50%, 30 minutos dos veces a la semana. El programa nutricional consistió en talleres de 2 horas cada semana. La cardiografía de impedancia y el análisis de la variabilidad de la frecuencia cardiaca (VFC) fueron realizados antes y después de la intervención. Resultados: El grupo de intervención disminuyó la presión arterial media en -7,8 mmHg (IC 95%, -12,84 a -2,75; p = 0,004) y el índice de resistencia vascular sistémica (RVS) en -864,29 dyn·s·m2/cm5 (IC 95%, -1506,31 a -222,26; p = 0,010); y aumentó, el índice de gasto cardiaco en 0,48 L/min/m2 (IC 95%, 0,14 a 0,83; p = 0,007). En la VFC se reportó una reducción en la relación LF/HF de -0,52 (IC 95%, -1,02 a -0,02; p = 0,040). Conclusiones: Una intervención de baile y educación nutricional disminuye la presión arterial y la RVS y tiene efectos favorables en el balance simpático-vagal en pacientes con SM.