Acute autonomic and cardiovascular responses of eccentric resistance training in different intensities associated with blood flow restriction: a controlled randomized clinical trial

• Grant number: 20/12239-1
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): February 01, 2021
• Effective date (End): December 31, 2021
• Field of knowledge: Health Sciences - Physiotherapy and Occupational Therapy
• Principal Investigator: Franciele Marques Vanderlei
• Grantee: Fernanda Santana dos Santos
• Host Institution: Faculdade de Ciências e Tecnologia (FCT). Universidade Estadual Paulista (UNESP). Campus de Presidente Prudente. Presidente Prudente , SP, Brazil

Abstract

Researchers on resistance training (RT) associated with blood flow restriction (BFR) have been suggested that this is an alternative method to gain strength and hypertrophy, however, the cardiovascular and autonomic repercussions of BFR associated with different intensities is not been elucidated. Thus, the investigation of the effects of this type of training on post-exercise recovery becomes relevant. Objective: investigate and compare acute autonomic and cardiovascular responses of eccentric exercise of different intensities associated or not with BFR in healthy young people. Methods: this is a randomized controlled clinical trial including 60 healthy men, aged between 18 and 35 years old, divided into four groups according to the intensity of exercise and BFR: 80% without BRF, 40% without BFR, 80% with BFR and 40% with BFR. The intensity of the exercise will be determined by the peak eccentric torque assessed by the Isokinetic dynamometry and the BFR will be determined as 40% of the pressure necessary for the complete restriction of blood flow assessed by vascular Doppler. The participants will perform a single session of eccentric exercise of the quadriceps femoris on the isokinetic dynamometer according to the previously randomized group. For recovery analyzes, cardiovascular parameters (heart rate, systolic and diastolic blood pressure, respiratory rate and partial oxygen saturation) and heart rate variability (HRV) indexes analyzed in the time domain (mean HR, rMSSD and SDNN), frequency domain (LF and HF [nu and ms2]) and Poincaré plot (SD1 and SD2). The analyzes will be performed at baseline, immediately after the exercise and in the post 60 minutes of the exercise. The descriptive statistical method will be used and the comparison of HRV indices and cardiovascular parameters between moments and groups will be performed using the technique of analysis of variance for a model of repeated measures in the two-factor scheme followed by post hoc tests. The level of significance will be p <0.05.