High intensity interval training versus strength training to improve insulin sensitivity in women with polycystic ovary syndrome - A randomized controlled trial

摘要

Background: Polycystic ovary syndrome (PCOS) is a common endocrine disorder affecting re-productive aged women. PCOS is associated with metabolic complications and an adverse cardiovascular disease (CVD) profile. Impaired insulin sensitivity is an important factor in the complex pathophysiology of PCOS. The prevalence of IR is higher in PCOS woman compared with weight-matched controls. Previous studies have shown a beneficial effect on IR after aerobic exercise with moderate intensity in women with PCOS. However, limited knowledge exists on the effect of high intensity interval training and strength training in this population. Objectives: The primary aim of the present study was to assess the possible effect of high intensity interval training (HIT) or strength training (ST) on insulin sensitivity among women with PCOS compared with a control group (CG). Fasting glucose and insulin c-peptide weremeasured as secondary outcomes. Methods: Thirty-one previously sedentary PCOS women were randomized to one of the following groups: high intensity interval training (HIT; n=10), strength training (ST; n=11) or control group (KG; n=10). The intervention period was ten weeks with exercise three times per week for HIT and ST. Insulin sensitivity calculated as «Homeostasis Model of Assessment - Insulin Resistance» (HOMA-IR), fasting plasma glucose and insulin c-peptide were evaluated and compared between groups. The mean changes in each group was reported as estimated marginal means (EMM), as assessed by 95 % confidence interval (CI) and considered significant if the 95 % CI did not include zero. Covariance analyses, with Bonferroni adjustment, were used to test difference between groups, with the difference as the dependent factor, group variable as the fixed factor, and baseline values as covariates. Results: Insulin sensitivity (HOMA-IR) was significantly improved by 21 % after HIT [EMM: -0.30, 95 % CI: -0.45 to -0.15] and by 17 % after ST [EMM: -0.23, 95 % CI: -0.43 to -0.02], and not in the CG. Fasting insulin c-peptide was reduced after HIT [EMM: - 0.11 nmol/l, 95 % CI: -0.19 to -0.04] and after ST [EMM: -0.11 nmol/l, 95 % CI: -0.20 to -0.02], and not in the CG. There were no significant changes in plasma glucose level in neither group. We found no between-group difference in the change in insulin sensitivity (p=0.41) or insulin c-peptide (p=0.61). Conclusion: These data indicate that ten weeks of regular HIT and ST have beneficial effect on insulin sensitivity in women with PCOS.