Respostas metabólicas durante e após sessões de exercício aeróbio de baixa intensidade com restrição de fluxo sanguíneo e intervalado de alta intensidade

Abstract

Introduction: aerobic exercise combined with blood flow restriction (AR+BFR) is being used as an alternative to the traditional high intensity training methods, however, regarding metabolic responses, it was verified that the lack of a standardized protocols on the researches with AR+BFR leads to limited conclusions on the excess post-exercise oxygen consumption (EPOC), energy expenditure and the use of energy subtract during and after training sessions. Aim: analyze the aerobic responses during and after exercise sessions of low intensity aerobic exercise (AE) with blood flow restriction (BFR) and high intensity interval training. Materials and methods: it is a quasi-experimental research with a cross over and randomized design, the sample was composed by twentytwo recreational athletes (age: 24.2 ± 2.8 years; body weight: 75.2 ± 8.2 kg; height: 176.6 ± 5.6 cm; body mass index: 24.1±1.9 kg/m²; e body fat: 15.6± 5.1 %), they underwent four experimental conditions with a seven-day washout between them: 1) CW+BFR – continuous walking at 40% of oxygen consumption peak (VO2peak) with 50% of BFR; 2) CW - continuous walking at 40% of VO2peak; 3) HIIT – high intensity interval training with six series of 90 seconds at 80% of VO2peak and active interval of 90 seconds of walking at 40% of VO2peak; and BFR – only the application of BFR technique without performing exercise. The experimental protocols had a time length of 18 minutes. The air was collected for 5 minutes before the sessions (rest), during protocols (18 minutes) and until 60 minutes after the end of the session. The aerobic energy expenditure of the session was measured by indirect calorimetry and the EPOC by the VO2, the QR during and after sessions was assessed by the relation between carbon dioxide production and oxygen consumption. Results: it was verified that aerobic energy expenditure on the HIIT protocol was significantly higher than the CW+BFR, CW and BFR (p<0.05) during exercise sessions (18 minutes), however, after exercise there were not significant differences between the HIIT and CW+BFR protocols (p>0.05). It was observed significant interaction between protocol x time, on the protocol and time (p<0.001) for the HR, VO2, QR and EPOC, after post-hoc analysis it was verified that the higher mean values were observed on the HIIT and CW+BFR protocols. Conclusion: the CW+BFR protocol promoted a higher energy expenditure than a session with the same intensity without BFR and a similar EPOC magnitude to the high intensity interval training.