Effects of different velocity loss thresholds on passive contractile properties and muscle oxygenation in the squat exercise using free weights

The current study assessed the impact between different velocity loss thresholds on changes in the muscle contractile properties and muscle oxygenation after a single resistance training session. 30 physically-active men participated in a cross-over study performing three sets of the squat exercise...

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Detalles Bibliográficos
Autores: Muñoz López, Alejandro, Marín Galindo, Alberto, Corral Pérez, Juan, Costilla, Manuel, Sánchez Sixto, Alberto, Sañudo Corrales, Francisco de Borja, Casals, Cristina, Ponce González, Jesús G.
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2022
País:España
Institución:Universidad de Sevilla (US)
Repositorio:idUS. Depósito de Investigación de la Universidad de Sevilla
OAI Identifier:oai:idus.us.es:11441/166607
Acceso en línea:https://hdl.handle.net/11441/166607
https://doi.org/0.1519/JSC.0000000000004048
Access Level:acceso abierto
Palabra clave:Fatigue
Velocity-based training
Muscle recovery
Neuromuscular properties
Strength training
Descripción
Sumario:The current study assessed the impact between different velocity loss thresholds on changes in the muscle contractile properties and muscle oxygenation after a single resistance training session. 30 physically-active men participated in a cross-over study performing three sets of the squat exercise at a lifted speed of ≈ 0.75 m·s -1, with two different velocity loss thresholds: 20% (VL20) vs 40% (VL40) in a randomized order. Contractile properties of the knee extensor muscles were tested using Tensiomyography. In addition, muscle oxygenation was continuously measured from baseline until the end of the exercise session. The Vastus Lateralis showed a significant Moment by Condition interaction in Time Delay (p=0.044), Muscle Displacement (p=0.001), and Contraction Velocity (p=0.007), with greater reductions in VL40. During the execution, the oxygenated haemoglobin and the tissue oxygen index decreased, while the deoxygenated haemoglobin increased (Moment as the main effect, p<0.05), but without a Moment by Condition interaction. In addition, VL40 showed a lower deoxygenation slope in Set 1 (-0.468 %·s-1, p= 0.001) and Set 3 (-0.474 %·s-1, p= 0.037) as well as higher losses in Set 1 (-41.50%, p=0.003), Set 2 (-41.84%, p= 0.002), and Set 3 (-62.51%, p<0.001). Finally, the recovery slope and increment during the first minute after each set were not significantly different between conditions. In conclusion, using a velocity loss of ≈ 40% resulted in higher neuromuscular impairment and more time under a lower oxygen supply compared to using a velocity loss of ≈ 20% in the squat exercise after a single resistance training session.