CYCLE SYNCING DEBUNKED?!

I’m proposing a new way of training…

I recently watched a clip of Dr Gabrielle Lyon’s podcast talking about cycle syncing, and calling it a myth. Then about 5 other similar ones popped up (thanks algorithm). Dr. Gabrielle Lyons is someone I deeply respect, so naturally it sent me down a research rabbit hole.

Because let’s be real, the internet is so freaken confusing!

One week, women are being told they need to restructure their food, training, work, social life and entire personality around a colour-coded 28-day cycle. The next, they are being told their hormones do not meaningfully affect training, cycle syncing is nonsense, and they need to stop using their period as an excuse.

And, as usual, the wellness and fitness industries have pushed us into two extremes…

Because extremes get clicks.

You can profit from telling women they need a different programme, meal plan and business strategy for every phase of their cycle. But you can also build a platform by dismissing cycle awareness completely and positioning yourself as the person who is finally “telling women the truth.”

Both sides are more polarising than the actual conversation.

My honest position on cycle syncing

Five years ago, I would have hand-on-heart told you cycle syncing was 100% the way women should train, eat, work and live.

I tried it with food. I tried it with training. I tried it with business. I tried it with lifestyle.

And I do not think there is no merit in it.

I think it gave women language for something we had been disconnected from for a very long time: we are NOT small men (to quote Dr. Stacy Sim’s).

We are not machines, our bodies do have rhythms that vary throughout the month, and blindly overriding them is not the same thing as having discipline.

But I also think we took something innately feminine; listening to your body, noticing your energy, understanding your cycle, responding to what you need and turned it into another rigid set of rules.

Another routine to execute perfectly.

Another way to get it “right.”

Another reason to feel like you have failed if you do not eat the prescribed food, do the prescribed workout or follow the prescribed work schedule for the exact phase you are in.

And I think that is where the pushback is coming from now.

The problem was never women becoming more aware of their cycles.

The problem was turning body literacy into a rigid formula.

What the research actually says

The newer research is fairly clear on one important point:

There is no compelling evidence that every naturally cycling woman needs to place more training volume in the follicular phase, avoid hard training in the luteal phase, or train a certain way around ovulation in order to build more muscle and strength.

A recent randomised controlled trial followed 24 healthy, regularly cycling women across roughly 12 weeks. It compared putting more resistance-training volume in the follicular phase, putting more in the luteal phase, and training consistently across both (PMID: 42160459).

All three approaches improved muscle and strength. Neither cycle-based approach was superior. Overall training volume was what mattered (PMID: 42160459).

A second highly controlled study measured muscle protein synthesis after resistance exercise in just 12 young naturally menstruating women. It used bloods, ovulation testing, stable isotopes and muscle biopsies to properly verify the phases. Exercise increased muscle protein synthesis, but cycle phase did not change that response (PMID: 39630025).

There is also a 2026 study that followed 28 resistance-trained women through real training over two mesocycles. It found cycle phase itself had only trivial effects on barbell velocity. Motivation to train and symptom profiles were more relevant to performance. (PMID: 42177355)

So if we’re just going off the literature, it would be apparent to say that our cycle isn’t impacting our training as females…

Look, I am not going to tell you that you will lose gains if you train in your luteal phase.

And I am definitely not going to tell women they need to spend two weeks of every month switching their training to yoga and walks instead of hitting the gym (but that is a hill I have always been ready to die on).

However… Here is where I think people are taking this research and making an equally unhelpful leap.

Calling cycle syncing a myth is insinuating female physiology is irrelevant!

The major 2020 meta-analysis on menstrual-cycle phase and exercise performance included data from 73 studies. Its conclusion was that exercise performance may be trivially reduced on average in the early follicular phase compared with other phases (PMID: 32661839).

Not hugely. Not for every woman. Not enough to create a universal programme.

But the authors also said the evidence was low quality, the variation between studies was huge, and general guidelines could not be formed. Their recommendation was a personalised approach based on each woman’s response across her own cycle.

That is a very different message from “the cycle has no relevance to training.”

THIS IS THE NUANCE! And it is exactly why this research warrants more, not less attention.

Because the studies being used to dismiss cycle awareness are still generally looking at small groups of healthy, regularly cycling women under controlled conditions.

The 2026 hypertrophy trial? 24 women.

The detailed muscle-protein-synthesis study? 12 women.

The recent real-world resistance-training study that tracked women over two training mesocycles? 28 women.

These are useful studies. It’s a step in the right direction in that at least female training is being studied in the first place. But they are not remotely representative of every woman hitting a gym class or working out at the gym.

Are they looking at women with painful periods? Heavy bleeding? Iron deficiency? Endometriosis? PCOS? PMS or PMDD? Perimenopause? Irregular or absent ovulation? Chronic stress? Poor sleep?

A nervous system that has been carrying far more than a controlled research protocol can account for?

Because those women exist. They are not outliers. And they deserve more than being told to train through whatever their body is trying to communicate because the average result from a small study did not find a universal hormonal effect.

So are we really going back to telling women to train like men?

I hope not.

Because women are not small men.

And before someone twists that into, “So women cannot train hard,” that is not what I am saying. I am one of the loudest advocates for women lifting heavy, building muscle, fueling properly, progressing their training and not shrinking themselves out of fear.

Women need strength training.
Women need muscle.
Women need to stop being conditioned to make themselves smaller.

But training women well cannot mean pretending the female body has no cyclical physiology, no hormonal changes, no symptom patterns and no individual variation.

The alternative to rigid cycle syncing cannot be a generic, one-size-fits-all training model that ignores female physiology altogether.

The goal is not to turn every woman’s cycle into a training limitation.

The goal is to stop treating female physiology like it disappears the second she walks into a gym.

Symptoms still matter

Personally, I know I am an N=1.

My own experience is not a clinical trial.

But real-time feedback from my body matters. And the feedback I see from real women in my practice matters too.

The amount of women I have seen have that “oh my gosh, the relief” moment when they realise they do not have to force themselves through the exact same training output all month is huge.

For some women, training through their period genuinely feels exhausting.

Maybe it is cramps. Maybe it is a migraine. Maybe it is poor sleep. Maybe it is a heavier bleed. Maybe it is low energy. Maybe it is a nervous system that is already overloaded. Maybe it is a combination of all of it.

And that is not an excuse to stop moving.

But it may mean choosing yoga over the HIIT class that day.

It may be reducing reps, changing the workout, taking longer rests or choosing a lower-stress session.

It may be training exactly as planned, because that is what feels good.

Or it actually might mean taking a day of rest without guilt because let’s face it, you’re bleeding, inflammation may be higher and pushing through something right now because you’re ‘supposed to’ isn’t going to make a difference to your results. If anything it will make you feel worse.

A heavy or painful period is not just something to override. I also do not want this conversation to become another way we normalise women suffering.

eavy menstrual bleeding is a major contributor to iron deficiency. Iron deficiency, even without anaemia, can affect energy, quality of life and capacity.

So if your period is suddenly heavier, more painful, disrupting your sleep, changing your energy or affecting how you function, that is not just a cue to push through harder.

It is information.
It is something to listen to.
It is something to investigate.

That is body literacy in practice.

Your period is not there to inconvenience you. Your cycle is feedback. Your symptoms are feedback. Your body is not being dramatic. It is communicating.

The new real-world resistance training research is actually useful here. It found the cycle phase itself had only trivial effects on barbell velocity, but motivation to train and symptom profiles still mattered. That does not mean symptoms dictate everything. It means they are part of the information we use.

Research informs the framework.

The woman in front of me informs the decision.

Cycle awareness is a tool, not a rulebook

For me, understanding my cycle does not mean I slow down or stop pushing myself in the gym. It gives me a framework to check in.

Sometimes I will train exactly as planned.

Sometimes I might skip the HIIT, pull back the volume, do fewer reps, take longer rests or move differently that day.

And if it is ovulation time and I feel good? I will push the crap out of my body.

But there are ovulation weeks where I do not feel like that too.

And that is information.

That is why I do not believe women need a universal cycle-syncing programme.
And I do not believe women need a universal “ignore your cycle and just train” programme either.

I believe women need education.

They need to understand what a natural, ovulatory cycle looks like. They need to understand their symptoms. They need to understand the difference between a normal variation in readiness and a pattern that deserves more support.

And we also need to acknowledge that many women do not have a natural, ovulatory cycle to map their training to in the first place. Women on hormonal contraception, in perimenopause, postpartum, with irregular or absent cycles, or managing reproductive health conditions need a different conversation. Generic phase-based advice may simply not apply.

That does not make body literacy less important.

It makes it more important.

My two cents…

I am not going to die on the hill that cycle syncing is a myth.

But I am also not going to say it is the only way women should train.

I think it is a tool.

I think it is an invitation to understand your body.

I think it can give women permission to stop overriding themselves, without turning their cycle into another rigid wellness routine they have to perform perfectly.

The goal is not to train less because you are a woman.

The goal is to know your body well enough to know when to push, when to adjust, and when a symptom is asking you to pay attention.

That is not weakness. That is not softness.
That is intelligent training.

Research referenced

• D’Souza et al. (2026), Menstrual Cycle Phase Does Not Influence Training-Induced Muscle Hypertrophy or Strength: A Randomized Controlled Trial. PMID: 42160459. Read the study
• Colenso-Semple et al. (2025), Menstrual cycle phase does not influence muscle protein synthesis or whole-body myofibrillar proteolysis in response to resistance exercise. PMID: 39630025. Read the study
• Munteanu et al. (2026), The Effect of Menstrual Cycle Phase, Symptoms, Motivation, and Readiness to Perform on Resistance Training Performance. PMID: 42177355. Read the study
• McNulty et al. (2020), The Effects of Menstrual Cycle Phase on Exercise Performance in Eumenorrheic Women: A Systematic Review and Meta-Analysis. PMID: 32661839. Read the study
• Blagrove, Bruinvels & Pedlar (2020), Variations in Strength-Related Measures During the Menstrual Cycle in Eumenorrheic Women: A Systematic Review and Meta-Analysis. PMID: 32456980. Read the study
• Munro & Mast (2023), The relationship between heavy menstrual bleeding, iron deficiency, and iron deficiency anemia. PMID: 36706856. Read the study