The acute effects of the administration of normobaric hypoxia during active recovery intervals of high-intensity interval running sessions

• Grant number: 23/11755-4
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: February 01, 2024
• End date: December 31, 2024
• Field of knowledge: Health Sciences - Physical Education
• Principal Investigator: Leonardo Coelho Rabello de Lima
• Grantee: Alexandre Souza de Oliveira
• Host Institution: Escola de Educação Física e Esporte de Ribeirão Preto (EEFERP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

Our aim is to investigate the acute effects of the administration of normobarid hypoxia (NH) during active recovery intervals of high-intensity interval training (HIIT) sessions in experienced runners. Participants will perform four HIIT sessions (six sets of four minutes of effort followed by three minutes of recovery) in different days in a randomized order. During two of these sessions, recovery will be passive (standing rest) and in the other two, recovery will be active (running at 90% of the speed associated with the ventilatory threshold [VT]). The efforts of all sessions will consist of running at a speed equivalent to 50% of the differences between the speeds associated with the respiratory compensation point (RCP) and maximal oxygen uptake (VO2max). NH (FiO2 - 12.6%) will be administered in a double-blind fashion during recovery intervals in one session with active recovery and one session with passive recovery. Our hypotheses are that: 1) the administration of NH during active recovery will increase total training load as a consequence of the incrise in the internal load during recovery, and 2) the reduction in oxygen suply during active recovery will result in the exacerbation of the physiological responses during the efforts but this will not compromise performance during the session. The dependent variables will be the internal load, perceived effort, mean heart rate and effort duration, and they will be compared among sesssions by one-way ANOVAs followed by Bonferroni post hoc tests, when appropriate. Significance level will be set as p < 0.05.