Bench Press With and Without Blood Flow Restriction on Hemodynamics and Pulse Wave Reflection

Hemodynamic and pulse wave reflection responses to upper-body resistance exercise (RE) with and without blood flow restriction (BFR) are unclear. PURPOSE: To evaluate the differences between bench press with and without BFR on hemodynamics and pulse wave reflection in resistance-trained men. METHODS: Sixteen resistance-trained men participated in the study. Hemodynamics and pulse wave reflection were assessed before and after low-intensity bench press with BFR (LI-BFR), traditional high-intensity bench press without BFR (HI), and control (CON). The LI-BFR utilized of 4 sets with repetitions of 30, 15, 15, and 15 at 30% 1-repetition maximum (1RM) and 30 seconds rest between sets. The HI consisted of 4 sets of 8 repetitions at 70% 1RM and 60 seconds rest between sets. The CON consisted of supine rest for 10 minutes. A repeated measures ANOVA was used to evaluate the conditions (LI-BFR, HI, CON) across time (rest, recovery) on hemodynamics and pulse wave reflection. RESULTS: There were significant (p≤0.05) increases in heart rate after LI-BFR (Rest: 57±10bpm; Rec: 62±11bpm) and HI (Rest: 57±14bpm; Rec: 69±13bpm) compared to rest and CON. There were no changes in aortic and brachial systolic blood pressure (BP) after any condition. However, there were significant (p≤0.05) reductions after HI-BFR in aortic (Rest: 66±9 mmHg; Rec: 61±6 mmHg) and brachial (Rest: 60±5 mmHg; Rec: 65±9 mmHg) diastolic BP compared to rest. There were significant (p≤0.05) condition by time interactions after LI-BFR and HI for augmentation index (AIx) (LI-BFR: Rest: 10.0±5.6%, Rec: 27.2±12.1%; HI: Rest: 12.2±9.0%, Rec: 22.3±8.1%), AIx at 75bpm (LI-BFR: Rest: 1.1±7.6%, Rec: 21.6±14.5%; HI: Rest: 4.5±12.7%; Rec: 19.5±10.4%), augmentation pressure (LI-BFR: Rest: 3.9±2.2 mmHg, Rec: 13.3±6.9 mmHg; HI: Rest: 5.2±3.9 mmHg, Rec: 9.6±3.7 mmHg) and wasted left ventricular energy (LI-BFR: Rest: 838±513dynes s/cm2, Rec: 2961±1743dynes s/cm2; HI: Rest: 1116±849dynes s/cm2, Rec: 1983±904dynes s/cm2) such that they were augmented compared to rest and CON, with no differences between LI-BFR and HI. CONCLUSION: These data suggest that LI-BFR significantly decreases aortic and brachial diastolic BP. In addition, LI-BFR and HI significantly alter pulse wave reflection in a similar fashion.