Author(s): FITAS, A., GIGGLINGER, S., PEZARAT-CORREIA, P., MENDONCA, G.V., Institution: UNIVERSITY OF LISBON FACULTY OF HUMAN KINETICS, Country: PORTUGAL, Abstract-ID: 416

INTRODUCTION:
The autoregulation of resistance training load is highly relevant for the field of strength and conditioning. Of all the regulation strategies presented in the literature, monitoring movement velocity and accessing the load-velocity relationship seems to be among the most reliable and objective [1,2]. Additionally, the individual load-velocity relationship can be attained through the two-point method, without the necessity of directly determining the one-repetition maximum (1RM) [3]. However, whether adjustments of load solely based on daily fluctuations of the load at zero velocity (LD0: y-intercept of the relationship) allow for a similar training stimulus - similar number of repetitions performed after the load adjustment, is unknown.
METHODS:
15 participants were evaluated on 3 distinct sessions. On all sessions, submaximal load-velocity relationships were obtained using the two-point method and participants performed a set of the free-weight back squat to failure. Training load was set at 80%1RM on one session, and on the subsequent sessions load was adjusted according to the magnitude of LD0 change. This training intensity was selected as it translates to a load compatible with hypertrophy, strength and power training. The validity of this methodology was examined via repeated measures ANOVAs, absolute mean differences, absolute-percent errors and Bland-Altman plots addressing the load adjustments (kg) and the number of repetitions performed on each session [4].
RESULTS:
Similar load adjustments and repetitions were performed on both subsequent sessions (mean absolute differences of ~1.5 kg and 1 repetition, respectively). The absolute mean differences in the number of repetitions performed was significantly inferior to 2. The Bland-Altman analysis revealed homoscedasticity for the load adjustments but not for the difference in number of repetitions performed for one of the testing sessions, revealing a lack of validation when a larger number of repetitions was performed.
CONCLUSION:
Overall, this methodology accommodates daily changes in maximal neuromuscular capacities and allows for resistance training practitioners to undergo a similar training stimulus. Regardless, some between subject variability was identified and, on some individual cases, the load adjustments may lead to an excessively different number of repetitions to be performed.

1. Suchomel et al. (2021) 2. Guppy et al. (2022) 3. García-Ramos (2023) 4. Bland & Altman (1999)