Exercise in PCOS

PCOS can be a difficult and complex disorder to manage. Lifestyle change incorporating exercise remains the first-line treatment.

Introduction

RECOGNISED as the leading cause of anovulatory infertility, polycystic ovary syndrome (PCOS) affects 12–18% of reproductive-aged women.1

PCOS is a complex disorder with complications extending beyond infertility to include metabolic and psychological manifestations. 

Diagnosis requires at least two of the following characteristics: clinical or biochemical hyperandrogenism, anovulatory menstrual dysfunction and polycystic ovaries on ultrasound, in the absence of secondary causes. 

Although not required for diagnosis, insulin resistance is strongly implicated in the aetiology of PCOS underpinning both reproductive and cardiometabolic disturbances and is present independent of obesity. Obesity affects 30% of women with PCOS and increases complications.2, 3 Lifestyle change with or without weight loss improves clinical features, including insulin resistance. 

For this reason, lifestyle modification, incorporating exercise, remains the first-line treatment for PCOS. 

Exercise, Diet or a combination

Diet and exercise, alone or in combination, have been shown to improve health outcomes in PCOS and therefore ideally they should be used together as part of a healthy lifestyle program to prevent weight gain in all those with a body mass index ≥ 20kg/m2 and for weight loss in those who are overweight.

When combined with dietary intervention, exercise has been shown to potentiate the effects of diet on reproductive and metabolic outcomes. Alone, exercise therapy has also been shown to improve reproductive and metabolic features independent of change in diet and without any change in weight.4

Maintaining a specific diet is difficult for many women over time and recent evidence suggests that caloric restriction appears to be more effective in reducing weight and improving clinical features in PCOS than modifying specific macronutrient content (i.e. increased protein, reduced carbohydrate, low glycaemic index, etc). 

Therefore, a healthy lifestyle incorporating a low-fat diet and regular exercise should be promoted.

Reproductive and Metabolic health

Previous research incorporating regular exercise at least three times per week (30–60 minutes) for 3–6 months’ duration has been effective in improving reproductive features, including menstrual regularity and ovulation rate.5,6

Results from a six-month study reported significantly higher menses frequency and cumulative ovulation rate following exercise in comparison to a low-caloric, high-protein diet alone5 further highlighting the importance of exercise therapy in PCOS. 

This research also reported a higher pregnancy rate with exercise (35% compared to 10% with diet).

The most consistent metabolic improvement with regular exercise in PCOS appears to be insulin resistance with either neutral or small changes noted to weight, body fat, waist-to-hip ratio, triglycerides and blood pressure. 

With insulin resistance underlying many of the complications in PCOS and impacting on progression to complications including type 2 diabetes, improvement is an important target for long-term health and should be emphasised to women with PCOS. 

Type of exercise 

Previous research has incorporated a variety of exercise interventions in PCOS and most have been effective in improving clinical features regardless of type, including moderate or vigorous aerobic exercise or resistance (weight bearing) exercise.  

Many women, including those with PCOS, may believe they need to partake in a variety of different exercise programs in order to achieve benefits. While variety is beneficial for motivation, it is not essential, and can include simple exercises such as walking for moderate activity. Intermittent vigorous activity is also recommended. 

The key to maintaining health benefits is ensuring sustainability of exercise over time and setting realistic goals.

Key recommendations

THE recently released Evidence Based Guideline for the Assessment and Management of PCOS, available at www.managingpcos.org.au and also in the September edition of The Medical Journal of Australia, evaluates exercise in PCOS and provides health professionals with key exercise recommendations for women. Essentially, the recommendation is to exercise for at least 150 minutes per week (e.g. five 30-minute sessions), and at least 90 minutes of this should incorporate moderate to vigorous aerobic activity (60–90% of maximum heart rate).

It is important to share with women that this degree of exercise assists in the prevention of weight gain but may not induce weight loss. Women should be encouraged to understand that the health benefits of exercise far exceed those of weight management to optimise motivation and sustainability.