Does baseline strength influence adaptations to velocity loss threshold-based resistance training?

OBJECTIVE

This study examined whether baseline strength moderates the magnitude of adaptations to velocity loss (VL) threshold-based resistance training across different training populations.

METHODS

A systematic search was conducted in PubMed, Web of Science, SPORTDiscus (EBSCO), and Embase up to January 2026. Randomized controlled trials were included if they implemented resistance training prescribed using predefined VL thresholds, lasted at least 3 weeks, reported quantifiable baseline strength data, and provided pre- and post-intervention measures of strength and/or power outcomes. Effect sizes were calculated as standardized within-group pre-post changes (Hedges' g). A three-level random-effects meta-regression model was applied to account for statistical dependence among multiple effect sizes within studies. Baseline strength (standardized 1RM) was examined as the primary moderator, with training status and VL threshold entered as additional moderators.

RESULTS

Sixteen studies providing 89 effect sizes were included. VL threshold-based resistance training produced a moderate overall within-group improvement in strength and power outcomes (g = 0.59, 95% CI [0.40, 0.77], p < 0.001). The omnibus test of moderators was not statistically significant (QM(4) = 1.09, p = 0.896). Baseline strength was not significantly associated with adaptation magnitude (β = -0.076, p = 0.355), and the interaction between baseline strength and training status was also not statistically significant (β = 0.045, p = 0.775).

CONCLUSION

VL threshold-based resistance training elicits moderate improvements in neuromuscular performance. Within the limitations of the available evidence, no statistically detectable moderation by baseline strength or categorical training status was observed. These findings suggest that current evidence does not clearly support modifying VL prescriptions solely on the basis of baseline strength; however, equivalence across populations cannot be definitively established.