The association between ischemic preconditioning and exercise performance: a systematic review and meta-analysis
Authors: Gorman Ellen , Senefeld Jonathon , Ovrom Erik , Clayburn Andrew , Joyner Michael , Burr Jamie , Wiggins Chad 
Published: May 2023

Purpose: The present work was performed to provide an updated and comprehensive systematic review and meta-analysis on the potential ergogenic effects associated with ischemic preconditioning (IPC). In this context, this systematic review and meta-analysis aimed to determine the magnitude of the potential ergogenic effect of IPC and the influence of descriptive factors that contribute to the variability of its potential ergogenic effect. We hypothesized that IPC would be associated with improved exercise performance, and putative factors would modulate this association. Methods: On October 17, 2022, a systematic search of three databases (PubMed, Scopus, and Web of Science) was performed. The electronic search yielded 2,876 unique records, of which 79 were included in analyses after abstract and full-text screening. Eligible study designs included within subjects cross-over, sham controlled study, with a randomized or counter balanced study design. Prespecified analyses aimed to determine whether the ergogenic effect of IPC is influenced by: 1) exercise parameters (type of exercise, fraction of inspired oxygen, and muscle group(s) involved in exercise) and 2) IPC parameters (dosage, duration, and timing before onset of exercise). Results: The meta-analysis model demonstrated that exercise performance was improved with IPC compared to the sham control (pooled standard paired difference (SPD), 0.156; 95% confidence interval (CI), 0.084 to 0.227; Z = 4.258; P < 0.001; n = 105). Both remote IPC (pooled SPD, 0.219; 95% CI, 0.071 to 0.368; Z = 2.894; P = 0.004) and local IPC (pooled SPD, 0.159; 95% CI, 0.088 to 0.231; Z = 4.386; P < 0.001) demonstrated ergogenic effects on performance. Subgroup analyses based on the fraction of inspired oxygen level revealed improved exercise performance in normoxic (pooled SPD, 0.169; 95% CI, 0.100 to 0.237; Z = 4.805; P < 0.001) but not hypoxic (pooled SPD, 0.160; 95% CI, -0.029 to 0.349; Z = 1.659; P = 0.097) conditions. The most notable improvement in exercise performance following IPC was demonstrated during cycling (pooled SPD, 0.116; 95% CI, 0.023 to 0.209; Z = 2.454; P = 0.014), running (pooled SPD, 0.180; 95% CI, 0.056 to 0.303; Z = 2.847; P = 0.004), and leg press (pooled SPD, 0.421; 95% CI, 0.034 to 0.808; Z = 2.131; P = 0.033) performance tests. Conclusion: Overall, IPC demonstrated a clear ergogenic effect on exercise performance across various exercise modalities under normoxic environmental conditions. The enhanced exercise performance following IPC was most pronounced in aerobic tests of performance which predominantly recruited large muscle groups in the lower extremities: cycling, running, and leg press. This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.