Effects of blood flow restricted staircase sprint snacks on body composition, anaerobic power, and muscle strength in physically inactive students

The purpose of this study was to examine the effects of a 6-week "staircase sprinting" (SS) with or without blood flow restriction (BFR) on body composition, anaerobic power, and leg muscle strength in physically inactive college students. Twenty-two physically inactive college students (11 males and 11 females) were randomly assigned to an experimental group (SS-BFR, n = 12) and a control group (SS, n = 10). Participants in both groups received SS snacks 3 days per week (3 times per day) for 6 weeks. The interval between each SS was greater than two hours. The SS-BFR group wore the BFR device during SS, which was measured using the estimated Arterial Occlusion Pressure(AOP). A 40% AOP was used in weeks 1-3 and increased to 50% AOP in weeks 4-6. Normal data were analyzed using one-way covariance analysis (ANCOVA), and non-normal data were analyzed using nonparametric ANCOVA (Quade's test). After the 6-week intervention, no intra- or inter-group differences in body composition were observed between the two groups (p > 0.05). Anaerobic power showed a significantly lower decrease in fatigue index (Pi) in the SS-BFR group than in the SS group (p = 0.047, ƞ²P = 0.191, 95% CI [0.075, 11.739]). However, no significant main effects were observed for peak power (PP), mean power (MP), and minimum power (MinP) between the groups (p > 0.05). The results of the isokinetic muscle strength test showed that, except for the right knee extensor muscle strength at 60 °/s, which exhibited a significant between-group difference (p = 0.033, F = 5.273), no other results demonstrated significant between-group main effects (p > 0.05). Surface electromyography (sEMG) results showed no significant between-group main effects for changes in vastus medialis (p = 0.093, ƞ²P = 0.141, 95% CI [-0.838, 9.965]) and vastus lateralis (p = 0.527, ƞ²P = 0.021, 95% CI [-5.629, 10.663]). Applying BFR during the SS period seems to enhance the participants' leg muscle strength and their ability to resist fatigue during anaerobic exercise. However, the effectiveness of this intervention must be determined in future studies, considering factors such as cuff pressure, gender and sample size.