OBJECTIVE: To evaluate the effects of a low-carbohydrate diet associated with strength training on the clinical signs of polycystic ovary syndrome (PCOS). RESEARCH METHODS AND PROCEDURES: A randomized clinical trial was carried out including 29 women over 18 years old diagnosed with PCOS, randomized into two groups, with follow-up for 12 weeks: the low-carbohydrate diet group associated with strength exercise (LCDE)
and the standard diet group associated with strength exercise (SDE). We evaluated manifestations of acne, hirsutism by the Ferriman-Gallwey scale and alopecia by the Ludwig-Savin scale, and assessed laboratory tests for total and free testosterone, dehydroepiandrosterone, follicle-stimulating hormone, and luteinizing hormone. The collected data were analyzed using IBM-SPSS software version 21. RESULTS: The study showed statistically significant differences in the hormonal levels of dehydroepiandrosterone (P = 0.045), luteinizing hormone (P = 0.017) and follicle-stimulating hormone (P = 0.014) when comparing the LCDE and SDE groups. CONCLUSIONS: the intervention used can promote an improvement in the clinical presentation of PCOS, especially in hormonal parameters. The clinical trial was registered on the REBEC platform (Brazilian Registry of Clinical Trials) under number RBR4wjqxcv (Carbohydrate Reduction and Exercise in Women with PCOS) and is available on the website: https://ensaiosclinicos.gov.br/rg/RBR-4wjqxcv.