Low-Load Blood-Flow Restriction Exercise to Failure and Nonfailure and Myoelectric Activity: A Meta-Analysis

• Published in: Journal of athletic training Vol. 57; no. 4; pp. 402 - 417
• Main Authors: Cerqueira, Mikhail Santos, Maciel, Daniel Germano, Barboza, Jean Artur Mendonça, Centner, Christoph, Lira, Maria, Pereira, Rafael, De Brito Vieira, Wouber Hérickson
• Format: Journal Article
• Language: English
• Published: United States National Athletic Trainers Association 01.04.2022
• Subjects: Bias; Blood-Flow Restriction; Electromyography; Eligibility; Evaluators; Exercise; Exercise - physiology; Hemodynamics; Humans; Intervention; Meta Analysis; Metabolism; Muscle Strength - physiology; Muscle, Skeletal - physiology; Muscular Strength; Outcome Measures; Participant Characteristics; Physical Fitness; Randomized Controlled Trials; Regional Blood Flow - physiology; Repetition; Resistance Training - methods; Sample Size; Scientific Concepts; Software; Strength training; Systematic review; Variables; Vascular occlusion; vascular occlusion exercise; volitional failure; muscle fatigue; electromyography; Kaatsu training
• ISSN: 1062-6050; 1938-162X
• DOI: 10.4085/1062-6050-0603.20

To compare the short- and long-term effects of low-load resistance training with blood-flow restriction (LL-BFR) versus low- (LL-RT) or high- (HL-RT) load resistance training with free blood flow on myoelectric activity and investigate the differences between failure (exercise performed to volitional failure) and nonfailure (exercise not performed to volitional failure) protocols. We identified sources by searching the MEDLINE, PubMed, CINAHL, Web of Science, CENTRAL, Scopus, SPORTDiscus, and PEDro electronic databases. We screened the titles and abstracts of 1048 articles using our inclusion criteria. A total of 39 articles were selected for further analysis. Two reviewers independently assessed the methodologic quality of each study and extracted the data. A meta-analytic approach was used to compute standardized mean differences (SMDs) ± 95% CIs. Subgroup analyses were conducted for both failure and nonfailure protocols. The search identified 39 articles that met the inclusion criteria. Regarding the short-term effects, LL-BFR increased muscle excitability compared with LL-RT during nonfailure protocols (SMD = 0.61; 95% CI = 0.34, 0.88), whereas HL-RT increased muscle excitability compared with LL-BFR during failure (SMD = -0.61; 95% CI = -1.01, -0.21) and nonfailure (SMD = -1.13; 95% CI = -1.94, -0.33) protocols. Concerning the long-term effects, LL-BFR increased muscle excitability compared with LL-RT during exercises performed to failure (SMD = 1.09; 95% CI = 0.39, 1.79). Greater short-term muscle excitability levels were observed in LL-BFR than in LL-RT during nonfailure protocols. Conversely, greater muscle excitability was present during HL-RT than LL-BFR, regardless of volitional failure. Furthermore, LL-BFR performed to failure increased muscle excitability in the long term compared with LL-RT.