(65) PERFORMING HIGH LOAD BENCH PRESS WITH BLOOD FLOW RESTRICTION DOES NOT SIGNIFICANTLY AFFECT BAR VELOCITY

Previous research has shown that using blood blow restriction (BFR) cuffs can increase peak velocity and power during high load (>65% one repetition maximum (1RM)) bench press exercise. Those previous studies, however, utilized high occlusion pressures i.e., greater than 80% arterial occlusion pressure (AOP). These higher occlusion pressures are typically applied to the lower body and may be too uncomfortable or painful during extended usage with the upper limbs.

Purpose: The purpose of this study therefore was to investigate the effects on power and velocity of a more moderate 50%AOP applied continuously during an acute high load bench press exercise.

Methods: 11 resistance trained males (age: 26.2 ± 6.6 yrs., wt.: 85.2 ± 10.5 kg, ht.: 177.9 ± 9.3 cm) participated in this study. This study employed a repeated measures design involving three visits. The first visit was to measure the 1RM for each participant in the bench press, with grip distance set to 150% biacromial distance for each participant. During the second and third visits, participants completed 4 sets of 4 reps of the barbell bench press with 75%1RM. Each visit was separated by 7-14 days, allowing participants to maintain their regular resistance training programs. During one of the visits, participants completed the bench press exercise with BFR cuffs applied to both arms and inflated to 50%AOP (‘BFR’), while the other session was completed without BFR (‘Control’). Mean and peak velocity (m/s) and power (W) were calculated by a GymAware Power Tool attached to one end of the barbell. The average value of the mean power (MP) and velocity (MV) for each set was recorded, while for peak power (PP) and velocity (PV) the highest value among the four reps was recorded. A series of two-way repeated measures ANOVAs (condition x set) with Bonferroni post hoc corrections were run for each of the four power and velocity variables.

Results: There were no significant (p>0.05) main effects for ‘Condition’ for any of the four variables (η_p² range: 0.004-0.06) nor were there any significant simple main effects for the interaction ‘Condition x Set’ (p>0.05) for all four variables (η_p² range: 0.06-0.11). There were no significant main effects for ‘Set’ (p>0.05) for MP (η_p²=0.20) or PP (η_p²=0.24); however, there were significant main effects for ‘Set’ for MV (p=0.017, η_p²=0.20) and PV (p=0.013, η_p²=0.297). Further analysis of the pairwise comparisons for both MV and PV variables revealed no significant differences between estimated marginal means of each set. For both conditions power and velocity increased from set to set.

Conclusions: Based on current data it appears that although BFR can increase power and velocity during high load bench press, this increase is not sufficiently large enough to be statistically different from high load bench press without BFR. PRACTICAL APPLICATIONS: Application of BFR at 50%AOP is not capable of producing significantly greater bar velocity or power during high load bench press. As such, coaches and athletes should look to other potential means or use higher, and potentially less comfortable, pressures of BFR to increase bar velocity and power during the bench press exercise.

Acknowledgements: None.