Repetições em Reserva (RIR)

Cross-sectional validity study (n=29: 15 experienced, 14 novice squatters) testing whether a repetitions-in-reserve (RIR) based RPE scale tracks bar velocity during a 1RM squat test and an 8-rep set at 70% 1RM. Strong inverse correlations between average velocity and RPE were found in both experienced (r=-0.88) and novice (r=-0.77) lifters, and experienced lifters reported higher RPE at 1RM than novices despite similar velocities at submaximal loads. This supports RIR-based RPE as a practical, velocity-correlated intensity-monitoring tool, but the study is a single acute cross-sectional comparison, not a longitudinal training trial, so it speaks to concurrent/construct validity rather than training outcomes.

Applied/narrative article (not a primary data study) explaining how to implement the repetitions-in-reserve (RIR) based RPE scale to autoregulate resistance-training loads on a set-by-set basis, arguing it can more precisely gauge near-limit intensity than session-level RPE and adjust loads to daily athlete capability. As a practical-application piece it synthesizes prior validity work (e.g., Zourdos et al. 2016) into coaching guidance rather than presenting new empirical findings.

Exploratory multilevel meta-regression series estimating repetitions-in-reserve (RIR) at set termination (estimated from training-intervention descriptions, a stated limitation) and its association with strength and hypertrophy, adjusting for load, volume-equating method, duration, and training status. In all best-fit models for strength, RIR's marginal slope confidence intervals contained zero (negligible relationship); for hypertrophy, slopes were consistently negative with CIs excluding zero, indicating greater hypertrophy as sets were taken closer to failure while strength gains were similar across a wide RIR range. The authors explicitly describe the models as exploratory with only modest overall fit and caution that exact RIR-outcome relationships remain unclear given the estimation procedure.

Systematic review/meta-analysis of 15 studies comparing resistance training to momentary muscular failure vs non-failure, 'set failure' (any definition) vs non-failure, or different velocity-loss thresholds, for muscle hypertrophy. A small, borderline-significant advantage was found for training to any definition of set failure over non-failure (ES=0.19, p=0.045), but no significant advantage emerged specifically for momentary muscular failure vs non-failure (ES=0.12, p=0.343), nor for high (>25%) vs moderate (20-25%) velocity-loss thresholds (ES=0.08, p=0.529) — suggesting a potentially non-linear relationship between proximity-to-failure and hypertrophy rather than a simple 'closer is always better' pattern.