Variability in the Relationship Between Velocity Loss and Percentage of Completed Repetitions During Horizontal Leg Press and Bench Press in Postmenopausal Women

Iglesias-Soler, E, Rial-Vázquez, J, Nine, I, Fariñas, J, Revuelta-Lera, B, and García-Ramos, A. Variability in the relationship between velocity loss and percentage of completed repetitions during horizontal leg press and bench press in postmenopausal women. J Strength Cond Res XX(X): 000-000, 2024-This study aimed to analyze the intersubject variability in the relationship between percentage of velocity loss (%VL) and percentage of repetitions performed out of maximum possible (%MNR) in postmenopausal women. Thirty-five postmenopausal active women (58 ± 3 years) performed sets leading to muscular failure, completing 10-13 repetitions, in both leg press (LP) and bench press (BP). Mean lift velocity of each repetition was expressed as a percentage of the fastest repetition, and repetitions were quantified as a percentage of the maximum number of repetitions completed in the set. Given the hierarchical structure of the data, %VL-%MNR relationships were fitted by linear mixed model regressions. A significant intersubject variability in the intercept (i.e., %MNR associated with 0%VL) was detected (p < 0.001 in both LP and BP), even when centered values of the completed repetitions were included in the models. The estimated variance in the intercept for LP (117.39; SE: 45.41) was almost double that for BP (67.47; SE: 20.27). The variability observed in the intercept entailed variability in the estimated %MNR for specific %VL values. The use of velocity loss thresholds for estimating the intensity of effort in active postmenopausal women does not overcome uncertainty of more traditional methods.