Effect of blood flow restriction and electrical muscle stimulation on human glycemic response to a glucose challenge

Abstract

Purpose: To determine whether reduced tissue oxygen availability through blood flow restriction (BFR) alone, or in combination with electrically induced muscle contractions, can improve glucose clearance after an acute glucose challenge.

Methods: In a randomized crossover design, 21 young participants (females: 12) were allocated to perform 1) electrical muscle stimulation (EMS), 2) BFR, 3) EMS + BFR or 4) no treatment (control). Participants completed each condition immediately preceding a 2 h oral glucose tolerance test (100 g). Primary analyses were performed on the glucose area under the curve (AUC) at time points 0-30, 30-120, and 0-120 min. Secondary analyses were performed on glycemic responses based on biological sex and estimated muscle phenotype.

Results: Compared to the control (322±25 mM∙min), the 0-30 min AUC was reduced following EMS (293±22 mM∙min, p = 0.0004), and EMS + BFR (298±36 mM∙min., p = 0.006), whereas BFR in isolation did not differ (306±30 mM∙min, p = 0.1). The 30-120 and 0-120 min glucose AUCs were similar across conditions. Based on effect size from the control conditions, our secondary analysis suggests different 0-30 min glycemic responses after EMS + BFR between females (d_z = 0.206) vs. males (d_z = 1.461) and/or slow (d_z = 0.426) vs. fast (d_z = 1.075) muscle phenotype.

Conclusion: Reducing tissue oxygen availability with BFR did not augment the effects of EMS in the overall group; however, we provide preliminary data to suggest possible sex and/or muscle phenotypic responses in glycemic regulation with these modalities.

Keywords: Glucose uptake; Glycemic regulation; Ischemia; Muscle contractions; Tissue oxygen availability.