Sánchez-Valdepeñas, JuanCornejo-Daza, Pedro J.Rodiles-Guerrero, LuisPaéz-Maldonado, Jose A.Sánchez-Moreno, MiguelBachero-Mena, BeatrizSáez de Villarreal Sáez, EduardoPareja Blanco, Fernando2026-03-022026-03-022024-06Sánchez-Valdepeñas, J., Cornejo-Daza, P. J., Rodiles-Guerrero, L., Páez-Maldonado, J. A., Sánchez-Moreno, M., Bachero-Mena, B., Saez de Villarreal, E., & Pareja-Blanco, F. (2024). Acute Responses to Different Velocity Loss Thresholds during Squat Exercise with Blood-Flow Restriction in Strength-Trained Men. Sports (Basel, Switzerland), 12(6), 171. https://doi.org/10.3390/sports1206017110.3390/sports12060171https://hdl.handle.net/10433/26324(1) Background: The aim of this paper is to analyze the acute effects of different velocity loss (VL) thresholds during a full squat (SQ) with blood-flow restriction (BFR) on strength performance, neuromuscular activity, metabolic response, and muscle contractile properties. (2) Methods: Twenty strength-trained men performed four protocols that differed in the VL achieved within the set (BFR0: 0% VL; BFR10: 10% VL; BFR20: 20% VL; and BFR40: 40% VL). The relative intensity (60% 1RM), recovery between sets (2 min), number of sets (3), and level of BFR (50% of arterial occlusion pressure) were matched between protocols. Tensiomyography (TMG), blood lactate, countermovement jump (CMJ), maximal voluntary isometric SQ contraction (MVIC), and performance with the absolute load required to achieve 1 m·s-1 at baseline measurements in SQ were assessed before and after the protocols. (3) Results: BFR40 resulted in higher EMG alterations during and after exercise than the other protocols (p < 0.05). BFR40 also induced greater impairments in TMG-derived variables and BFR10 decreased contraction time. Higher blood lactate concentrations were found as the VL within the set increased. BFR0 and BFR10 showed significantly increased median frequencies in post-exercise MVIC. (4) Conclusions: High VL thresholds (BFR40) accentuated metabolic and neuromuscular stress, and produced increased alterations in muscles' mechanical properties. Low VL could potentiate post-exercise neuromuscular activity and muscle contractile properties.application/pdfenAttribution-NonCommercial-NoDerivatives 4.0 Internationalhttp://creativecommons.org/licenses/by-nc-nd/4.0/FatigueMetabolic ResponseNeuromuscularResistance trainingTensiomyographyjournal articleopen access