Mubarra Rao  ( Ziauddin College of Rehabilitation Sciences, Ziauddin University, Karachi, Pakistan. )
Amna Aamir Khan  ( Ziauddin College of Rehabilitation Sciences, Ziauddin University, Karachi, Pakistan. )
Qurat Ul Ain Adnan  ( Ziauddin College of Rehabilitation Sciences, Ziauddin University, Karachi, Pakistan. )

Objective: The current systematic review was planned to provide quality assessment of different exercise regimes and their outcomes on the symptoms of polycystic ovary syndrome, and to see if one exercise regime was better than the rest.

 

Methods: Search was conducted on PubMed and Google Scholar databases for studies published between 2001 and 2021 whose full text was available. The search yielded 28 studies that were reviewed.

 

Results: The current evidence suggests that exercise regimes, such as high-intensity interval training, progressive resistance training, aerobic exercises, and yoga may improve polycystic ovary syndrome conditions. This is accomplished through treating associated risk factors, like body morphology, insulin resistance, hyperandrogenism, lipid profile, reproductive hormones, menstrual cycle, and quality of life.

 

Conclusion: Exercise regimes improves several symptoms of polycystic ovary syndrome. However, selecting a specific exercise regime over others as the standardised treatment protocol remained inconclusive.

 

Key Words: Polycystic ovarian syndrome, Exercises, High-intensity interval training, Aerobic exercises.

 

DOI: 10.47391/JPMA.5187

 

Submission completion date: 03-01-2022

 

Acceptance date: 08-09-2022

 

Introduction

 

Polycystic ovary syndrome (PCOS) is a complex multifactorial disorder. It is a common endocrinopathy impacting females of reproductive age, globally affecting 20% of the women¹. Different diagnostic criteria define PCOS with the presence of clinical or/and biochemical hyperandrogenism, long-term anovulation, hirsutism, acne, oligomenorrhea and infertility. Rotterdam criterion 2003 is the standard used for diagnostics, while the Androgen Excess and PCOS Society Criterion 2006 (AE-PCOS) is another common criterion for PCOS^2,3.

PCOS is associated with several ailments, such as cardiometabolic, psychological and reproductive disorders⁴. The most common cardiometabolic conditions representing high risk for PCOS women are high blood pressure (BP), altered lipid profile, insulin resistance (IR), insulin-resistant diabetes, non-alcoholic fatty liver, and cardiovascular diseases⁵. PCOS is also associated with psychological distress that indicates a high risk of anxiety, depression, stressfulness and high sensitivity due to low self-esteem and negative body image. These risk factors, in turn, negatively affect the health-related quality of life (HRQOL) ⁶.

The recommended first line of management for PCOS is lifestyle modification which can effectively reduce IR, improve metabolism and reproductive functions, promote weight loss which further restores ovulation and menstrual cycle. Being physically active and losing weight are advised for managing PCOS symptoms^7,8. Different exercise interventions have been studied, evaluating the effects on improving PCOS features. Moderate exercises, resistance exercise, and aerobic exercise, as treatment of the clinical complication of PCOS, are considered to be beneficial due to their positive impact on other insulin-resistant populations in the absence of weight loss^9,10. Several reviews and analyses about the management of PCOS over the years have stated beneficial outcomes of exercise training, but the literature in support of one exercise regime over the other till date remains lacking and inconclusive⁸. Several review and analysis have focussed on one or two outcome measures have never entirely focussed on exercise alone. The current systematic review was planned to summarise the effects of different exercise regimes on body morphology, metabolic, reproductive, cardiovascular and psychological features among females with PCOS in the hope of proving one exercise regime to be superior to other regimes in managing PCOS.

 

Materials and Methods

 

The current systematic review was conducted as per the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines¹¹, and was registered with the international Prospective Register of Systematic Reviews (PROSPERO) reg no: CRD42021267721¹².

Sampling method: Literature was selected by thorough search on PubMed and Google Scholar databases for studies published from 2001 to 2021 and whose full text was available. The search strategy included key words, like PCOS, exercise, high-intensity interval training (HIIT), progressive resistance training (PRT), yoga, strength training, aerobic exercise, physical activity, etc. (Table 1). Inclusion and exclusion criteria were outlined in detail (Figure 1)

 

 

 

The data extracted from the studies included primary author's name, publication year, study arms, sample sizes, study design, demographic details, like body mass index (BMI), as well as clinical details, like the diagnostic criterion used for PCOS, the type of control group, type of intervention, duration, frequency of exercise, randomisation of subjects, and significant primary and secondary outcome pre- and post-intervention data. If available, p-value and confidence interval (CI) were also extracted.

Primary outcome measures: IR, body weight, BMI, waist circumference (WC), body fat percentage and mass (% or kg), free androgen index (FAI), testosterone, Modified Ferriman-Gallwey score, epiandrosterone/ Dehydroepiandrosterone- Sulfate (DHEA/DHEA-S), number of follicles, Luteinizing hormone (LH), follicular stimulating hormone (FSH) and sex hormone-binding globulin (SHBG).

Secondary outcome measure: Lipid profile, high-density lipoprotein (HDL), low-density lipoprotein (LDL), total cholesterol (TC), triglycerides (T), systolic blood pressure (SBP), diastolic blood pressure (DBP), maximal oxygen consumption (VO2max), HRQOL, Depression, Anxiety, Stress Scale-21 (DASS-21), Polycystic Ovary Syndrome Questionnaire (PCOSQ-50), Short Form-36 (SF-36), Beck anxiety inventory (BAI) score, and Beck’s depression inventory-II (BDI-II) score.

Assessment of RCT quality: The quality and internal validity, along with the risk of bias of all the included RCTs, were evaluated. For this purpose, the 15-point tool for the assessment of study quality and reporting in exercise scale (TESTEX scale) and the Modified Cochrane Collaboration tool were used to assess the risk of bias for RCTs¹³.

 

Results

 

Of the 311 RCTs found, 28(9%) were reviewed (14-41) (Figure 2).

 

 

Attributes of RCTs in the review:  The total number of participants was 1367 (range: 12-94).

Characteristics of interventions: Overall, 21(75%)studies reported a comparison between aerobic exercises with a control group (with/without intervention), 3(10.7%) studies compared HIIT with a control group, 3(10.7%) studies focussed on yoga with a control group (conventional physical therapy), and 1(3.6%) study focussed on PRT with a control group without intervention. The duration of intervention was 10 weeks, 12 weeks, 16 weeks, and 26 weeks (6 months), exercise intensity in most studies was either moderate or high, and aerobic exercises, HIIT, PRT, yoga and physical activity showed significant results post-intervention on a rage of parameters (Table 2).

 

 

On the basis of the TESTEX scale, it was noted among other things, that the eligibility criteria were described in all the studies, statistical data reported in the RCTs was constant, and the limitation of RCTs was primarily associated with lack of data or lack of blind allocation of groups, failure to evaluate the outcome measures, and failure to either mention or implement the intention-to-treat (ITT) analysis (Table 3).

 

 

Risk of bias: All the RCTs reviewed were evaluated for risk of bias. The majority of the RCTs demonstrated a high risk

of bias for blinding outcome assessment, and a low risk of bias for blinding participants or personnel (Table 4,  Figure 3).

 

 

 

Discussion

 

The current systematic review provides evidence from the last 20 years, with 1367 subjects, for the sole purpose of reinforcing the need to use exercise as an intervention option for managing PCOS. It is known that lifestyle modification, the first line of management of PCOS, includes exercise⁴². The RCTs in the current review included sample sizes ranging from 12 to 94 participants, where only one study had 94 participants. Six studies included 84-90 participants, while others ranged from 12-66 participants, while the study with the least number of participants had 12 subjects. The effectiveness of different exercise training among PCOS patients was evaluated, and mode, frequency, intensity, and duration of exercise regimes were studied. The effects of exercise on metabolic functions, cardiovascular functions, reproductive functions, psychological wellbeing, and anthropometrics were studied.

Statistically significant post-intervention outcome values compared to the values taken at baseline were observed across all the 28 studies. The majority of studies reported improvement in insulin sensitivity, reduction in IR, and improvement in blood lipid profile. IR, insulin sensitivity, lipid profile, free testosterone, total testosterone, SHBG, DHEA, androstenedione, FAI, oestradiol, prolactin, anti-müllerian hormone (AMH), and adiponectin showed favourable outcomes. Exercise improved menstrual condition and reduced the number of ovarian follicles. For the restoration of ovarian function, insulin sensitivity needs to be improved. Homeostatic model assessment for insulin resistance (HOMA-IR) is an indicative tool used to assess IR, and different exercise interventions were studied for effectiveness in reducing IR. Seven studies reported significantly lower HOMA-IR after aerobic, HIIT, PRT and yoga interventions^{22,27,28,30,33,35,40}.

Fasting insulin and fasting glucose were reported to be significantly improved in 5 studies, while TG, TC, HDL and LDL significantly improved in 6 studies^{15,16,18,19,22,27,30,31,40,41} ). All the improvements were either in the presence or absence of weight loss. In 10 weeks of HIIT, there was no weight reduction, but several other features changed significantly, like improved IR, reduced AMH, and fat percentage. Without weight loss, HIIT significantly improved the cardiometabolic profile among the PCOS population²⁷. Aquatic HIIT significantly reduced BMI, FSH, FT, SHBG, HOMA-IR, and hirsutism severity, and improved menstrual cycle³⁵.

PCOS women with increased BMI tend to have metabolic manifestations with increased risk of IR and cardiovascular diseases, thus impacting the hormonal control related to ovulation. Several studies reported that aerobic exercise improves various biomarkers related to health, with 12 weeks of aerobic exercise showing significant improvements in weight loss, FSH, oestrogen, antral follicle count, AMH, and adiponectin. These outcomes correlated significantly with the improvement in reproductive function. In women with anovulation, significant improvements in the ovarian process and a restoration of the menstrual cycle were seen. Several parameters of the Polycystic Ovary Syndrome Questionnaire-50 (PCOSQ-50) and the ratio of LH and FSH and free serum testosterone were reported to have significantly improved. Besides, 16 weeks of aerobic exercise improved menstrual frequency and hyperandrogenism. The visceral adiposity index also significantly improved. Furthermore, high-sensitivity C-reactive protein (hs-CRP) and HOMA-IR decreased. The data showed that in PCOS women, the regulation of lipolysis by the main endocrine hormones as impaired, but the lipolytic defects can be partly reversed by aerobic exercise training independent of changes in body fat mass and sex hormones. It was reported that aerobic fitness and insulin sensitivity significantly increased independent of weight loss. Also, reduction in the total number of follicles was observed after aerobic exercise for 16 weeks. Continuous aerobic training (CAT) and intermittent aerobic training (IAT) also significantly lowered the anthropometric profile, while also improving the condition of hyperandrogenism. In contrast, only IAT training reduced FAI, while CAT improved the lipid profile. Six months of HIIT and CAT showed improvement in fasting glucose, BMI, and lipid profile compared to the control group^{15-21,25,26,28,30-34,36,38-41}.

PRT was reported to have improved several HRQOL domains, particularly vitality, physical functioning, social functioning, role emotional, and mental health. It also decreased BMI and WC, thus improving body composition. PCOSQ showed that exercise improved weight and infertility issues. Depression was also treated as DASS score showed improved depression, anxiety and exercise self-efficacy scale scores²⁹.

Yoga intervention was reported to have significantly lowered free testosterone and DHEA levels without weight reduction. Additionally, yoga showed betterment in measures of anxiety and depression. It was reported that this improvement seemed long-lasting even when the treatment ended. A holistic yoga programme also significantly reduced AMH, LH, testosterone, and hirsutism, while menstrual frequency, body weight and FSH remained unchanged. Some studies though reported that weight reduction is the most significant way to restore ovulation in obese women with PCOS. Several studies reported exercise-induced reductions in cardiometabolic risk factors without significant weight loss, suggesting the notion that in the future, the sole interest of exercise programmes should not be weight reduction, and more research is needed for a concrete basis^22,24,37.

 

Limitations: Several RCTs included in the review had weaknesses related to the inadequate blinding of patients and examiners, failure to evaluate the outcome measures in some RCTs, and failure to either implement or mention the ITT analysis and mention of any adverse effect. Only a few studies had follow-ups. Most RCTS focused on aerobic exercise, and only a handful of studies studied the effects of HIIT, PRT and yoga.

 

Strength: The systematic review provides detailed knowledge of the impact of physical therapy or exercise on several different parameters and characteristic symptoms of PCOS.

 

Future recommendations: More trials are needed to be conducted on the interventions mentioned in the current review that will open a wide range of research area to establish the most efficient therapeutic programme for the PCOS population. Considering how IR and hyperandrogenism are involved in the pathophysiology of PCOS, future studies should focus on them.

 

Conclusion

 

Evidence suggests that exercise potentially benefits PCOS women by reducing and improving various risk factors, like IR and hyperandrogenism. Exercise regimes, such as aerobic exercise, HIIT, PRT and yoga, significantly reduce the complications associated with PCOS. However, with the present data, it cannot be concluded which exercise regime is superior and more significant than the other regimes.

 

Acknowledgement: We are grateful to all those who supported and encouraged us throughout the project.

 

Disclaimer: None.

 

Conflict of Interest: None.

 

Source of Funding: None.

 

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