AUTHOR=Slysz Joshua T. , Burr Jamie F. 

TITLE=Enhanced Metabolic Stress Augments Ischemic Preconditioning for Exercise Performance

JOURNAL=Frontiers in Physiology

VOLUME=9

YEAR=2018

URL=https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2018.01621

DOI=10.3389/fphys.2018.01621

ISSN=1664-042X

ABSTRACT=<p><bold>Purpose:</bold> To identify the combined effect of increasing tissue level oxygen consumption and metabolite accumulation on the ergogenic efficacy of ischemic preconditioning (IPC) during both maximal aerobic and maximal anaerobic exercise.</p><p><bold>Methods:</bold> Twelve healthy males (22 ± 2 years, 179 ± 2 cm, 80 ± 10 kg, 48 ± 4 ml.kg<sup>−1.</sup>min<sup>−1</sup>) underwent four experimental conditions: (i) no IPC control, (ii) traditional IPC, (iii) IPC with EMS, and (iv) IPC with treadmill walking. IPC involved bilateral leg occlusion at 220 mmHg for 5 min, repeated three times, separated by 5 min of reperfusion. Within 10 min following the IPC procedures, a 30 s Wingate test and subsequent (after 25 min rest) incremental maximal aerobic test were performed on a cycle ergometer.</p><p><bold>Results:</bold> There was no statistical difference in anaerobic peak power between the no IPC control (1211 ± 290 W), traditional IPC (1209 ± 300 W), IPC + EMS (1206 ± 311 W), and IPC + Walk (1220 ± 288 W; <italic>P</italic> = 0.7); nor did VO<sub>2</sub>max change between no IPC control (48 ± 2 ml.kg<sup>−1</sup>.min<sup>−1</sup>), traditional IPC (48 ± 6 ml.kg<sup>−1</sup>.min<sup>−1</sup>), IPC + EMS (49 ± 4 ml.kg<sup>−1</sup>.min<sup>−1</sup>) and IPC + Walk (48 ± 6 ml.kg<sup>−1</sup>.min<sup>−1</sup>; <italic>P</italic> = 0.3). However, the maximal watts during the VO<sub>2</sub>max increased when IPC was combined with both EMS (304 ± 38 W) and walking (308 ± 40 W) compared to traditional IPC (296 ± 39 W) and no IPC control (293 ± 48 W; <italic>P</italic> = 0.02).</p><p><bold>Conclusion:</bold> This study shows that in a group of participants for whom a traditional IPC stimulus was not effective, the magnification of the IPC stress through muscle contractions while under occlusion led to a subsequent exercise performance response. These findings support that amplification of the ischemic preconditioning stimulus augments the effect for exercise capacity.</p>