Effects of a 12-Week Moderate-Intensity Aerobic Exercise Program on Cardiometabolic Biomarkers in Sedentary Middle-Aged Adults: A Randomized Controlled Trial

Abstract

Background: Sedentary behavior is a well-established contributor to cardiometabolic disease risk in middle-aged adults, yet the comparative efficacy of moderate-intensity continuous aerobic training on multiple biomarkers simultaneously remains incompletely characterized. Objective: This study examined the effects of a 12-week moderate-intensity aerobic exercise program on fasting glucose, lipid profile, resting blood pressure, and cardiorespiratory fitness in previously sedentary middle-aged adults. Methods: Eighty-four sedentary adults (mean age 47.6 ± 6.2 years) were randomized to a supervised aerobic exercise group (n = 42, three 40-minute sessions per week at 60-70% heart rate reserve) or a non-exercising control group (n = 42). Outcomes were assessed at baseline and week 12. Results: The exercise group demonstrated significant improvements relative to control in fasting glucose (-6.8 mg/dL, p < 0.001), low-density lipoprotein cholesterol (-9.4 mg/dL, p = 0.002), systolic blood pressure (-5.1 mmHg, p = 0.004), and estimated VO2max (+3.9 mL/kg/min, p < 0.001). No significant between-group change was observed for high-density lipoprotein cholesterol (p = 0.21). Conclusion: A structured 12-week moderate-intensity aerobic exercise program produced clinically meaningful improvements across multiple cardiometabolic risk markers in sedentary middle-aged adults, supporting its use as a first-line, low-cost intervention in preventive health programs.