Polycystic Ovary Syndrome and Exercise

Polycystic Ovary Syndrome (PCOS) is a common hormonal disorder characterized by oligo-ovulatory menstrual dysfunction, androgen excess and polycystic ovaries. It affects ten to fifteen percent of reproductive-age women and has been associated with complications in reproductive, metabolic and cardiovascular health. Current Clinical Practice Guidelines suggest exercise and weight loss for PCOS, although their specific roles in improving PCOS-related symptoms are uncertain.

Non-pharmacological treatments are appealing to many reproductive age women. There is preliminary evidence that exercise in PCOS may increase menstrual regularity, ovulation, cardiorespiratory fitness, health-related quality of life (HRQOL) and self-esteem, and decrease body fat and insulin resistance. These studies have been limited by short durations and lack of randomization or appropriate control groups.

High-intensity interval training (HIIT), which involves brief intervals of near-maximal exercise alternating with lower-intensity exercise, is becoming increasingly popular in the exercise community. In some non-PCOS trials, HIIT resulted in improved cardiovascular fitness and greater fat loss compared with continuous aerobic exercise. No other trials are currently on-going that are comparing HIIT with continuous aerobic exercise training in women with PCOS (as confirmed by searches of the literature and the clinical trials registry maintained by the US NIH).


Eligibility Criteria:
Inclusion Criteria:

* Participants will be eligible for inclusion if they are females between the ages of 18 and 40 years with a diagnosis of PCOS according to the 2003 revised Rotterdam criteria, confirmed by a qualified member of our research team. Participants will have at least two of the three following criteria:

  1. Oligo-ovulation or anovulation. Oligo-ovulation is defined as menstrual cycles greater than 35 days or less than 8 menstrual cycles per year. Anovulation is defined as no ovulation in more than 90 days.
  2. Clinical and/or biochemical signs of hyperandrogenism. Clinical hyperandrogenism is defined as a modified Ferriman Gallwey score greater than or equal to 8. Biochemical hyperandrogenism is defined as a free androgen index greater than or equal to 5.1.
  3. Polycystic ovaries defined as the presence of 12 or more follicles in each ovary measuring 2-9 mm in diameter, and/or increased ovarian volume (\>10 mL).

Exclusion Criteria:

* Participants must not have a diagnosis of or clinical evidence of Cushing's syndrome, androgen-secreting tumours, congenital adrenal hyperplasia including classical and non-classical, uncontrolled thyroid dysfunction, diabetes, hemoglobin A1c greater than or equal to 6.5%, hypogonadotropic hypogonadism, premature ovarian insufficiency, or hyperprolactinemia.
* Participants must not be pregnant or breastfeeding within the three months prior to enrolment and must not be using or have used a hormonal contraceptive within three months of enrolment.
* Participants will be excluded if they are taking any medications to treat insulin resistance including metformin, medications likely to increase insulin resistance such as corticosteroids, or any medications that may affect ovulation including clomiphene citrate, letrozole, or gonadotropins. They must not be taking medications to treat hirsutism including spironolactone.
* Participants must not be habitually exercising more than two times per week for more than twenty minutes per session.
* Participants must be able to participate in the exercise intervention, therefore will be excluded if they have a physical injury, illness or disability that prevents them from doing so.