Hypertrophic effects of low-load blood flow restriction training with different repetition schemes: a systematic review and meta-analysis

Objective . This systematic review and meta -analysis analyzed the effect of lowload resistance training (LL-RT) with blood flow restriction (BFR) versus high -load resistance training (HL-RT) on muscle hypertrophy focusing on the repetition scheme adopted. Methods . Four databases were searched to identify randomized controlled trials that compared the effect of LL-RT with BFR versus HL-RT on muscle hypertrophy. Standardized mean differences (SMD) were pooled in a random effects meta -analysis. Results . The overall analysis did not demonstrate significant differences between conditions (SMD = 0.046; p = 0 .14). A similar result was observed when we separately analyzed studies that used sets to momentary muscle failure (SMD = 0.033; p = 0 .520), sets of 15 repetitions (SMD = 0.005; p = 0 .937) and a fixed repetition scheme composed of 75 repetitions (SMD = 0.088; p = 0 .177). The analysis considering body region indicates no difference in lower limb exercise between HL-RT and LL-RT with BFR (SMD = 0.00066; p = 0 .795) while upper limb exercise favors HL-RT (SMD = 0.231; p = 0 .005). Conclusion . LL-RT with BFR elicits muscle hypertrophy similar to HL-RT regardless of the employed repetition scheme, although there appears to be a small beneficial effect in favor of HL-RT in upper limb exercise.