HONOLULU – An hour of vigorous exercise per week decreased the risk for metabolic syndrome in women with polycystic ovary syndrome by 22%, a retrospective study of 326 women found.
Moderate-intensity exercise for at least 150 minutes per week also was beneficial, compared with inactivity, but vigorous exercise produced added benefits in risk for metabolic syndrome, body mass index (BMI), cholesterol levels, glucose tolerance, and insulin resistance, Dr. Eleni A. Greenwood said at the annual meeting of the American Society for Reproductive Medicine.
The results point to “the power of sweat” when recommending exercise to women with polycystic ovary syndrome (PCOS), she said.
Dr. Eleni A. Greenwood
The observational study of women seen at a single PCOS clinic in 2006-2013 compared three groups: those who reported exercising vigorously for at least 75 minutes per week; those who reported moderate-intensity exercise for at least 150 minutes per week but not vigorous exercise, or “inactive” women who reported neither of these activity levels, which are recommended by the U.S. Department of Health & Human Services.
Patients reported activity on the self-administered International Physical Activity Questionnaire, which defines vigorous exercise as hard physical effort that makes you breathe much harder than normal and moderate-intensity exercise as moderate physical effort that makes you breathe somewhat harder than normal. They were evaluated systematically for evidence of metabolic dysfunction.
Among the 56% of women who reported activity that met HHS recommendations, 83% reported vigorous activity and 17% reported moderate activity. The other 44% were classified as inactive.
The proportion of women with metabolic syndrome was lowest in the vigorous activity group (33%), higher in the moderate activity group (36%), and highest in the inactive group (47%), reported Dr. Greenwood of the University of California, San Francisco, and her associates.
Doing 60 minutes of vigorous exercise per week decreased the odds of metabolic syndrome by 22% after adjusting for the influence of age, BMI, and total volume of exercise as measured by metabolic equivalents, she said.
There was a significant trend toward lower BMI with more intense activity. The mean BMI was 27 kg/m2 in the vigorous activity group, 30 kg/m2 in the moderate activity group, and 31 kg/m2 in the inactive group, she said. The mean HDL cholesterol level was significantly higher in the vigorous exercise group (56 mg/dL), compared with the moderate exercise group (46 mg/dL) or the inactive group (51 mg/dL).
Measures of glucose tolerance using the 2-hour oral glucose tolerance test trended significantly better in the vigorous exercise group – a mean of 93 mg/dL with vigorous exercise, 104 mg/dL with moderate exercise, or 106 mg/dL in the inactive group. Fasting glucose measurements did not differ significantly between groups.
Significant trends toward better measures of insulin resistance were seen with more vigorous activity. Fasting insulin levels were 6.9 mU/L in the vigorous exercise group, 9.8 mU/L with moderate exercise, and 11 mU/L in the inactive group. Scores on the homeostatic model assessment of estimated insulin resistance were 1.5 in the vigorous exercise group, 2.2 in the moderate exercise group, and 2.4 in the inactive group.
Significant trends toward smaller waist circumference and rate of acanthosis nigricans were seen with more vigorous activity. The mean waist circumference was 33 inches in the vigorous exercise group and 35 inches in the other two groups. In the vigorous exercise group, 24% had acanthosis nigricans, compared with 30% in the moderate exercise group and 40% in the inactive group.
The mean age in each group was 28 years.
“Vigorous activity is associated with additional benefits, compared to moderate activity,” Dr. Greenwood said. “Women with PCOS should strive to meet HHS guidelines through vigorous physical activity.”
She reported having no financial disclosures. Her associates reported associations with Nora Therapeutics, Ferring Pharmaceuticals, and Ziva Medical.
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