A randomised controlled trial on the effect of ultrasound cavitation on insulin resistance, abdominal skinfold thickness, and waist-to-hip ratio in women with central obesity

Introduction This study aimed to evaluate the effects of ultrasound cavitation on insulin resistance, waist-to-hip ratio (WHR), and abdominal skinfold thickness in women with central obesity. Methods A total of 52 women aged 25–40 years with the mean age of 32.9 ± 4.2 years with central obesity were randomly assigned to either an experimental group (ultrasound cavitation, aerobic exercise, and a low-calorie diet) or a control group (aerobic exercise and a low-calorie diet). Randomisation was computer-generated; outcome assessors were blinded. The intervention occurred twice weekly for 6 weeks. Outcomes were assessed pre- and post-treatment. Insulin resistance was measured using the Homeostatic Model Assessment for Insulin Resistance (HOMA-IR), abdominal skinfold thickness with Lange callipers, and WHR with a non-elastic tape. Normality was confirmed via the Shapiro–Wilk test, and homoscedasticity was verified. Parametric tests including paired t-tests and multivariate analysis of variance (MANOVA) were applied, with Bonferroni correction used for multiple comparisons. Results The experimental group showed reductions of 23% in HOMA-IR (mean change: −0.64 ± 0.2), 7% in abdominal skinfold thickness (2.4 ± 0.5 mm), and 8% in waist-to-hip ratio (7.5 ± 1.2). In contrast, the control group demonstrated smaller reductions of 5% (0.13 ± 0.2), 0.5% (0.16 ± 0.1 mm), and 0.7% (0.63 ± 0.2), respectively. Between-group differences in all three obesity markers were statistically significant (p < 0.05), favouring the experimental group. Conclusions Ultrasound cavitation, combined with exercise and dietary interventions, significantly improves insulin resistance and central obesity markers. This finding supports its use as a non-invasive metabolic intervention.