Impact of systemic hypoxia and blood flow restriction on mechanical, cardiorespiratory, and neuromuscular responses to a multiple-set repeated sprint exercise

Robert Solsona; Roméo Dériaz; Simon Albert; Maxime Chamoux; Jaume Lloria-Varella; Fabio Borrani; Anthony M J Sanchez

doi:10.3389/fphys.2024.1339284

Impact of systemic hypoxia and blood flow restriction on mechanical, cardiorespiratory, and neuromuscular responses to a multiple-set repeated sprint exercise

Front Physiol. 2024 Jan 31:15:1339284. doi: 10.3389/fphys.2024.1339284. eCollection 2024.

Authors

Robert Solsona^{1

2}, Roméo Dériaz^{1

2}, Simon Albert³, Maxime Chamoux², Jaume Lloria-Varella², Fabio Borrani^#¹, Anthony M J Sanchez^#^{1

2}

Affiliations

¹ Institute of Sport Sciences, University of Lausanne, Lausanne, Switzerland.
² University of Perpignan Via Domitia, Laboratoire Interdisciplinaire Performance Santé Environnement de Montagne, Font-Romeu, France.
³ University of Rennes, Faculty of Sports Sciences, Rennes, France.

^# Contributed equally.

Abstract

Introduction: Repeated sprint cycling exercises (RSE) performed under systemic normobaric hypoxia (HYP) or with blood flow restriction (BFR) are of growing interest. To the best of our knowledge, there is no stringent consensus on the cardiorespiratory and neuromuscular responses between systemic HYP and BFR during RSE. Thus, this study assessed cardiorespiratory and neuromuscular responses to multiple sets of RSE under HYP or with BFR. Methods: According to a crossover design, fifteen men completed RSE (three sets of five 10-s sprints with 20 s of recovery) in normoxia (NOR), HYP, and with bilaterally-cuffed BFR at 45% of resting arterial occlusive pressure during sets in NOR. Power output, cardiorespiratory and neuromuscular responses were assessed. Results: Average peak and mean powers were lower in BFR (dz = 0.87 and dz = 1.23, respectively) and HYP (dz = 0.65 and dz = 1.21, respectively) compared to NOR (p < 0.001). The percentage decrement of power output was greater in BFR (dz = 0.94) and HYP (dz = 0.64) compared to NOR (p < 0.001), as well as in BFR compared to NOR (p = 0.037, dz = 0.30). The percentage decrease of maximal voluntary contraction of the knee extensors after the session was greater in BFR compared to NOR and HYP (p = 0.011, dz = 0.78 and p = 0.027, dz = 0.75, respectively). Accumulated ventilation during exercise was higher in HYP and lower in BFR (p = 0.002, dz = 0.51, and p < 0.001, dz = 0.71, respectively). Peak oxygen consumption was reduced in HYP (p < 0.001, dz = 1.47). Heart rate was lower in BFR during exercise and recovery (p < 0.001, dz = 0.82 and p = 0.012, dz = 0.43, respectively). Finally, aerobic contribution was reduced in HYP compared to NOR (p = 0.002, dz = 0.46) and BFR (p = 0.005, dz = 0.33). Discussion: Thus, this study indicates that power output during RSE is impaired in HYP and BFR and that BFR amplifies neuromuscular fatigue. In contrast, HYP did not impair neuromuscular function but enhanced the ventilatory response along with reduced oxygen consumption.

Keywords: high intensity exercise; hypoxic training; neuromuscular fatigue; recovery; skeletal muscle; vascular occlusion.

Grants and funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article. This project was funded by the University of Lausanne and the University of Perpignan Via Domitia (Bonus Qualité Recherche). Open access funding was provided by the University of Lausanne.