From PCOS to PMOS: Why Exercise Physiology Is Central to Managing a Whole-Body Condition
- Maddie Cherry
- Jul 25
- 5 min read
Maddie Cherry, Exercise Physiologist - Move Sports Physiotherapy
For decades, Polycystic Ovarian Syndrome (PCOS) has been framed as an ovarian and fertility problem. But that framing misses most of what's actually going on. A growing push to rename the condition PMOS — Polyendocrine Metabolic Ovary Syndrome, reflects a more accurate understanding, that this is a complex, whole-body endocrine condition that happens to have reproductive consequences, not a localised ovarian disorder.
That distinction matters enormously, because it changes the treatment. And one of the most powerful adjunctive treatments available isn't a medication. It's exercise.
Why the name change to PMOS?
The "cysts" in PCOS aren't true cysts at all. On ultrasound, what appears as a classic "string of pearls" is actually a collection of numerous small follicles that have accumulated around the ovary because ovulation has stalled. In a typical cycle, a cohort of follicles develops, one becomes dominant, ovulation occurs, and the rest regress. In PMOS, more follicles than usual start developing, a dominant follicle often fails to emerge, ovulation is delayed or absent, and those small follicles build up around the ovarian periphery.
We can now articulate that PMOS is simultaneously a metabolic, endocrine, reproductive, dermatological and psychological condition. And is so widely under-recognised, the World Health Organization has noted that around 70% of those with the condition are undiagnosed.
The metabolic engine driving it all
Understanding why exercise works so well requires understanding the underlying cascade:
Insulin resistance develops — the body's cells are responding poorly to insulin.
This leads to hyperinsulinaemia (chronically high insulin), which disrupts glucose and hormone regulation.
High insulin drives increased ovarian androgen production (testosterone, androstenedione, DHEAS).
That hormonal disruption produces menstrual dysfunction, weight gain and visceral fat; which creates a negative cycle loop, worsening insulin resistance and perpetuating itself.
Insulin resistance is the central driver here: an estimated 75–95% of women with PMOS have insulin resistance, with consequences extending far beyond the ovaries. Such as central adiposity, dyslipidaemia, chronic low-grade inflammation, metabolic syndrome, poor fertility, and a significantly elevated risk of gestational diabetes and type 2 diabetes.
Exercise as first-line therapy
The 2023 international guidelines position lifestyle management — exercise and nutrition — as first-line therapy for everyone with PMOS.
The reason exercise and nutrition are the foundation for PMOS treatment, is due to the sheer breadth of impact. Exercise is one of the few interventions that positively influences nearly every major manifestation of PMOS at once:
Insulin sensitivity - directly addressing the root driver
Reduced visceral fat
Menstrual regularity
Improved fertility outcomes
Mood and quality of life
Cardio-metabolic risk reduction
Few medications can claim to touch the metabolic, reproductive, psychological and cardiovascular dimensions simultaneously like exercise.
How does an Exercise Physiologist help?
The expertise of an Exercise Physiologist becomes valuable, due to their clinical knowledge in tailoring exercise protocols to an individual based on their health presentation and history.
The answer isn't "just do more cardio." Each exercise modality can contribute something distinct:
Aerobic exercise: walking, cycling, running, intervals, can all improve insulin sensitivity, cardiovascular fitness and helps reduce visceral fat.
Resistance training: is often under-utilised despite being highly relevant to insulin resistance. It builds lean muscle mass, improves glucose disposal, and raises resting metabolic rate. Given the central role of insulin resistance in PMOS, strength work deserves far more emphasis than it typically receives.
High-Intensity Interval Training (HIIT): can produce strong insulin-sensitivity gains in a time-efficient package — but it isn't right for everyone, and adherence matters more than chasing a "perfect" protocol.
The skill lies in matching the prescription to the individual: their history, preferences, confidence and starting point. A program someone actually enjoys, and sticks with will always outperform a theoretically optimal one they abandon.
Why the scales are the wrong scoreboard
One of the most important shifts an Exercise Physiologist can help facilitate is moving away from weight as the primary measure of success.
Body weight tells us very little about fitness, muscle mass and quality, insulin sensitivity, functional capacity or psychological wellbeing.
For example; two women of identical weight can differ enormously in VO₂max, insulin resistance, visceral fat, strength and overall cardiometabolic risk.
Crucially, exercise often produces major health improvements before any substantial weight loss occurs.
Consider the evidence that fitness matters more than weight:
Cardiorespiratory fitness: is one of the strongest predictors of cardiovascular disease risk, type 2 diabetes risk, all-cause mortality and metabolic health. A 10–15% improvement in VO₂max can meaningfully lower health risk even if the scales barely move.
Muscle is a metabolic organ: skeletal muscle drives most insulin-mediated glucose disposal. More muscle mass means greater glucose storage; better muscle quality means better insulin sensitivity; greater strength means better metabolic health.
The goal, in other words, is building metabolic infrastructure — not simply burning calories.
No weight change, DOES NOT mean no benefit
The benefits that accrue from exercise are substantial, even when body weight changes are minimal: Improved insulin sensitivity, reduced fasting insulin, better menstrual regularity, improved ovulation, better mental health and reduced visceral adiposity.
This reframing isn't just feel-good messaging, it's clinically important.
For many women with PMOS, a weight-centric approach is associated with lower physical activity, worse mental health, healthcare avoidance and poorer long-term behaviours. A weight-inclusive framework that tracks meaningful outcomes — VO₂max or estimated aerobic fitness, six-minute walk distance, strength gains, waist circumference, HbA1c and fasting insulin, menstrual regularity, energy and sleep, and confidence with exercise — keeps the focus on health measures that have lasting benefits.
The mental health dimension
Behaviour change can't be separated from psychology, and women with PMOS carry a heavier mental health load: roughly four times the likelihood of anxiety, two and a half times the likelihood of depression, higher rates of body image and skin concerns, and a three- to sixfold increased risk of disordered eating.
This is why, in practice, how support is delivered often matters more than fine-tuning sets and reps. Motivational interviewing, self-compassion-based approaches, long-term habit formation, and a deliberate shift in focus from weight loss toward building muscle and capability tend to produce better, more sustainable results than obsessing over exercise variables.
What it looks like in practice
A practical, Exercise Physiologist-guided program for someone with PMOS might start with:
Initial goals: "movement snacking," 2–3 resistance sessions per week, 150+ minutes of moderate aerobic activity weekly, reduced sedentary time, and daily walking targets.
Resistance training: built on compound movements with progressive overload — squats, hinges, pushes, pulls and carries.
Behaviour focus: prioritising consistency, enjoyment and sustainability over calorie expenditure.
The bottom line
Exercise is one of the very few interventions that improves metabolic, reproductive, psychological and cardiovascular outcomes simultaneously. An Accredited Exercise Physiologist brings the clinical knowledge to translate that potential into a personalised, sustainable, weight-inclusive plan, that targets the real driver of the condition and meets each client where they are.
This article is for general educational purposes and isn't a substitute for individualised medical or allied health advice. If you have PMOS/PCOS, consider working with an Accredited Exercise Physiologist and your GP or endocrinologist to develop a plan that's right for you.
