Neuromuscular Electrical Stimulation: A Novel Treatment Intervention for Improving Metabolic Health in an Overweight/obese Population
Background: Most U.S. adults (80%) do not meet minimum exercise recommendations by ACSM (CDC, 2015). Using an in vitro primary cell culture model, we and others have shown that muscle contraction induced by electrical stimulation results in increased glucose transporter 4 (GLUT4) protein, glucose uptake and mitochondrial content. Neuromuscular electrical stimulation (NMES) is a novel alternate strategy to induce muscle contraction, using electrical impulses. However, effectiveness of NMES induced muscle contraction to improve insulin sensitivity and energy expenditure is not clear. The purpose of this study was to investigate the effects of four weeks of NMES on insulin sensitivity in a sedentary overweight/obese population. Methods: Sedentary overweight/obese participants (n=10; age: 36.8 ± 3.8 years; BMI= 32 ± 1.3 kg/m2) were randomized into either a control or NMES group. All participants received bilateral quadriceps stimulation (12 sessions; 30 minutes/session; 3 times/week) either using low intensity sensory level (control) or at high intensity neuromuscular level (NMES) for four weeks (50Hz and 300μs pulse width). Insulin sensitivity was assessed by three-hour oral glucose tolerance test (OGTT), substrate utilization was measured by indirect calorimetry and body composition was measured by dual X-ray absorptiometry at baseline and after four weeks of NMES intervention. Results: Control and NMES group had comparable fasting blood glucose (p=0.42), glucose tolerance (p=0.49), substrate utilization (p=0.99), and muscle mass (p=0.86) at baseline. Four weeks of NMES resulted in a trend to improvement in insulin sensitivity measured by OGTT, whereas no change was observed in control group (Control 430.73 ± 20.23 to 494.68 ± 77.21 AU; p=0.76; NMES 455.55 ± 26.07 to 415.36 ± 25.89 AU; p=0.07). There was no change in substrate utilization in control (p=0.26) and NMES (p=0.85). In addition, there was no change in muscle mass in both control (p=0.14) and NMES (p=0.17) groups. Conclusion: NMES is a novel and effective strategy to improve insulin sensitivity in an at-risk overweight/obese sedentary population in the absence of substrate utilization and muscle mass improvement.
Galvan, Michelle Josie, "Neuromuscular Electrical Stimulation: A Novel Treatment Intervention for Improving Metabolic Health in an Overweight/obese Population" (2019). ETD Collection for University of Texas, El Paso. AAI27671533.