Comparison of the load-velocity relationship between bilateral and unilateral variants of the prone bench pull and leg press exercises

This study aimed to compare the load-velocity profiles (LVP) derived from bilateral and unilateral variations of the prone bench pull (PBP) and leg press (LP) exercises, considering the self-reported preferred (SP) and non-preferred (NP) sides. Eighteen competitive male rowers (16.5 ± 1.0 years) completed incremental loading tests to determine the LVP during the PBP and LP exercises, performed in separate testing sessions. Linear and second-order polynomial regression models were used to assess the LVP. The goodness-of-fit for both generalized and individualized LVPs was strong and consistent across exercise variants and models ( R² ≥ 0.753 and 0.903, respectively). Mean velocity significantly differed between exercise variations (40–50% of one-repetition maximum [1RM] for PBP [ P ≤ 0.038] and 90–100%1RM for LP [ P ≤ 0.043]) and between regression models (40–90%1RM for PBP [ P ≤ 0.044]). Specifically, i) velocity was generally higher in the bilateral variant compared to the unilateral NP variant of the PBP exercise ( P ≤ 0.106; ES = 0.49), and in the unilateral NP variant compared to the bilateral variant of the LP exercise ( P ≤ 0.088; ES ≥ 1.04), and ii) polynomial models produced slightly higher velocities than linear models (ES ≤ 0.12). These findings suggest that LVPs can be applied interchangeably between unilateral SP and NP variants of the PBP and LP exercises, regardless of the regression model used. However, a mode-specific approach may be needed for the bilateral variants to optimize load prescription accuracy.