Comparison Between Concentric-Only and Eccentric-Concentric Load-Velocity Relationships and its Derived Parameters in the Jump Squat and Bench Press Throw Exercises

ABSTRACT: Hernandez-Davo, JL, Sabido, R, Asencio, P, and Boullosa, D. Comparison between concentric-only and eccentric-concentric load-velocity relationships and its derived parameters in the jump squat and bench press throw exercises. J Strength Cond Res XX(X): 000-000, 2026-The aim of this study was to analyze 2 different load-velocity (L-V) assessment protocols (concentric-only [CON] vs. maximal intended eccentric velocity [MAX]) on the L-V relationship in jump-squat (JS) and bench press throw (BPT) exercises, 18 men performed the L-V relationship assessments with loads representing 20, 40, 60, and 80% of one repetition maximum (1RM) on 2 different days. Reliability was assessed using intraclass correlation coefficient (ICC) and coefficient of variation (CV%). The mean propulsive velocity (MPV) was used to establish individual L-V profiles, their derived parameters (L0 and V0), and estimated 1RM values in back-squat and bench press exercises. Maximal intended eccentric velocity condition showed high reliability (ICC: 0.70-0.87: CV: 4.2-11.2%), whereas CON condition showed moderate-to-high scores (ICC: 0.61-0.86; CV: 4.8-10.4%). The mean propulsive velocity values were significantly higher in the MAX condition at all loads in the JS (8.9-10.9%) and at all loads except the 20% 1RM in the BPT exercise (6.1-23.3%). When using the MAX condition, L0 values were higher in the BPT exercise (5%), and V0 was greater in both the JS (9.0%) and BPT exercises (3.4%). The estimated 1RM value was higher in the MAX condition for both the squat (124.1 vs. 117.8 kg) and the bench press exercises (89.2 vs. 83.9 kg). High-velocity eccentric actions led to significantly higher MPV values, without compromising reliability values. The L-V profile and their derived parameters are substantially affected by eccentric velocity instructions. Standardized protocols using maximal eccentric velocities are suitable to assess athletes' maximal neuromuscular performances with reliable L-V profiles, which may complement the information obtained through the habitual CON protocol.