• Gomes, Miguel
• Santos, Paulo
• Mendonca, Goncalo V.
• Fitas, Afonso
• Pezarat-Correia, Pedro

Abstract

<jats:title>Abstract</jats:title><jats:p>Gomes, M, Fitas, A, Santos, P, Pezarat-Correia, P, and Mendonca, GV. Validation of a single session protocol to determine the load-velocity profile and one-repetition maximum for the back squat exercise. <jats:italic toggle="yes">J Strength Cond Res</jats:italic> XX(X): 000–000, 2024—We investigated whether a single session of absolute incremental loading is valid to obtain the individual load-velocity profile (LVP) and 1 repetition maximum (1RM) for the free-weight parallel back squat. Twenty strength-trained male subjects completed 3 testing sessions, including a baseline 1RM session and 2 LVP sessions (LVP<jats:sub>rel</jats:sub> based on incremental relative loads and LVP<jats:sub>abs</jats:sub> based on absolute load increments until 1RM). The 1RM load was compared between the baseline and LVP<jats:sub>abs</jats:sub>. The load at zero velocity (load-axis intercept [L<jats:sub>0</jats:sub>]), maximal velocity capacity (velocity-axis intercept [V<jats:sub>0</jats:sub>]), slope, and area under the load-velocity relationship line (A<jats:sub>line</jats:sub>) were compared between the LVP<jats:sub>rel</jats:sub> and LVP<jats:sub>abs</jats:sub> using equivalence testing through 2 one-sided <jats:italic toggle="yes">t</jats:italic>-tests. Measurement accuracy was calculated using the absolute percent error. The 1RM measured at baseline and LVP<jats:sub>abs</jats:sub> was equivalent and presented a low absolute percent error (1.2%). The following LVP parameters were equivalent between LVP<jats:sub>rel</jats:sub> and LVP<jats:sub>abs</jats:sub>: 1RM, L<jats:sub>0</jats:sub>, and A<jats:sub>line</jats:sub> because the mean difference between sessions was close to zero and the Bland-Altman limits of agreement (1RM:5.3 kg; L<jats:sub>0</jats:sub>:6.8 kg; A<jats:sub>line</jats:sub>: 9.5 kg·m<jats:sup>−1</jats:sup>·s<jats:sup>−1</jats:sup>) were contained within the a priori defined ± equivalent margins (5% for 1RM and L<jats:sub>0</jats:sub> and 10% for A<jats:sub>line</jats:sub>). The aforementioned variables presented a low absolute percent error. However, slope and V<jats:sub>0</jats:sub> were not equivalent between sessions. In conclusion, a single session of absolute incremental loading is a valid approach to obtain the L<jats:sub>0</jats:sub> and A<jats:sub>line</jats:sub> of the individual LVP and 1RM, and can be used to efficiently track the magnitude of neuromuscular adaptations throughout the training cycles for the free-weight back squat.</jats:p>

Topics

• impedance spectroscopy
• strength