Efectos del ejercicio de resistencia continuo e intermitente sobre el balance autonómico, la escala de esfuerzo percibido y los niveles de lactato en sangre en sujetos sanos / Effects of continuous and intermittent endurance exercise in autonomic balance, rating perceived exertion and blood lactate levels in healthy subjects

RESUMEN

Objetivo: La finalidad de este estudio fue determinar los cambios en el balance autónomo, la percepción subjetiva del esfuerzo (PSE), y el lactato sanguíneo después de un protocolo de ejercicio aeróbico continuo y uno intermitente. Resultados: El balance autónomo no reflejó diferencias significativas entre ambos protocolos (p = 0,60). La RPE durante el ejercicio INTT fue considerablemente superior al ejercicio CONT (p = 0,01). Los niveles de lactato en sangre no reflejaron diferencias significativas (p = 0,68). Los parámetros de variabilidad de la frecuencia cardiaca en el dominio del tiempo (RR medio y pNN50) no reflejaron diferencias estadísticas entre ambos protocolos, con mediciones previas y a las 24 h del ejercicio (p = 0,24 y p = 0,61, respectivamente). Conclusiones: Los datos sugieren que el ejercicio intermitente se percibe más intenso que el continuo, aunque ambos protocolos reflejaron cargas internas similares en cuanto a balance autónomo y niveles de lactato en sangre. The data suggest that intermittent exercise is perceived more intense than continuous, although both protocols showed similar internal loads in autonomic balance and blood lactate levels

ABSTRACT

Purpose: The aim of this study was to determinate the changes in the Autonomic Balance, Rating Perceived Exertion (RPE) and blood lactate after continuous versus intermittent exercise protocols. Methods: Seven active and healthy male (33 ± 5.1 years) participated in the study. Each subject performed two exercise protocols: (i) a continuous exercise at 110% of the lactate threshold (CONT); the CONT protocol consisted in continuous running, and the distance covered was the same in meters as it was in the intermittent session, and (ii) an intermittent exercise at 100% of the Peak Treadmill Velocity (INTT). The protocol consisted of 30 min of 15 s running, interspersed with 15 s of passive rest. Autonomic balance was assessed through the LF/HF ratio, before beginning the exercises, immediately finishing the exercises and 24 h post-exercise; RPE was evaluated every 5 min in each exercise protocol; and blood lactate was measured immediately after both protocols. Alpha level was set at P ≤ .05. Results: Autonomic balance did not show significant differences between protocols (P = .60). RPE during INTT exercise was significantly higher than CONT exercise (P = .01). Blood lactate levels after exercise did not show significant differences (P = .68). Heart rate variability parameters in the time domain (mean RR and pNN50) show no statistical differences between both protocols pre and 24 h post exercise (P = .24 and P = .61, respectively). Conclusions: The data suggest that intermittent exercise is perceived more intense than continuous, although both protocols showed similar internal loads in autonomic balance and blood lactate levels