Impact of Ischemic Intra-Conditioning on Power Output and Bar Velocity of the Upper Limbs.

Michal Wilk,Pawel Krol,Petr Stastny,Michal Krzysztofik,Katarzyna Leznicka,Gregory C Bogdanis,Adam Zajac,Jakub Jarosz

doi:10.3389/fphys.2021.626915

Abstract

This study evaluated the effects of ischemic conditioning on power output and bar velocity in the bench press exercise. Ten healthy males (age: 25 ± 2 years; body mass: 92 ± 8 kg; bench press one repetition maximum −1RM: 145 ± 13 kg), took part in two experimental sessions (with and without ischemia), 1 week apart in random and counterbalanced order. In the ischemic condition, cuffs placed around the upper part of the arms were inflated to 80% of arterial occlusion pressure before each set, while in the control condition there was no blood flow restriction. The exercise protocol included 5 sets of three repetitions each, against a resistance equal to 60% 1RM, with 5 min recovery intervals between sets. There was a main effect of condition for mean power output (MP) and mean bar velocity (MV) (p = 0.01), with overall MP being higher in ischemia than in control by 5.6 ± 4.1% (mean ± 90% compatibility limits), a standardized effect size (ES) of 0.51. Overall MV was also higher by 5.5 ± 4.0%, ES = 0.63. Peak power output (PP) and peak bar velocity (PV) were similar in set 1 of the control and ischemia condition (1039 ± 105 vs. 1054 ± 82 W; 684 ± 74 vs. 696 ± 53 W; 1.09 ± 0.07 vs. 1.12 ± 0.09 m/s; 0.81 ± 0.05 vs. 0.82 ± 0.05 m/s, p = 0.67 to 0.99, mean ± standard deviation). However, from set 3 onward (p = 0.03 to 0.001), PP and PV were higher in ischemia compared with control, with the highest difference observed in set 5 (10.9 ± 5.9%, ES = 0.73 for PP and 8.6 ± 4.6%; ES = 0.89 for PV). These results indicate that ischemia used before each set of the bench press exercise increases power output and bar velocity and this may be used as performance-enhancing stimulus during explosive resistance training.

Highlights

Ischemia, referred to as blood flow restriction and occlusion, can be used in any form of physical activity and much attention has been devoted to the use of ischemia during resistance training (Wilk et al, 2018)
Since the bench press is a basic resistance exercise for developing upper body strength and power (Dunnick et al, 2015; Stastny et al, 2017; Wilk et al, 2019a, 2020d), the present study aimed to evaluate the effects of ischemia used during the rest interval between successive sets of the exercise on bar velocity and power output during the bench press exercise
There was a main effect of condition for mean power output (MP) and mean bar velocity (MV) (p = 0.01), with overall MP and MV being higher in ischemia

Summary

Introduction

Referred to as blood flow restriction and occlusion, can be used in any form of physical activity and much attention has been devoted to the use of ischemia during resistance training (Wilk et al, 2018). The ischemic preconditioning stimulate the release of nitric oxide (Kimura et al, 2007; Li et al, 2012), as well as the activation of the adenosine receptors (Liu et al, 1991; Schroeder et al, 1996), causing vasodilation after blood reperfusion (Kimura et al, 2007; Li et al, 2012), increasing O2 extraction by the muscle (Paradis-Deschênes et al, 2016; Tanaka et al, 2018), and opening of adenosine triphosphate (ATP)-dependent potassium (K+) channels which increase the energy stores after ischemia (Lawson and Downey, 1993; Pang et al, 1995)

Methods

Results

Discussion

Conclusion