The menstrual cycle has become an important topic in women’s training. That is a positive change. For a long time, menstruation, contraception and premenstrual symptoms were barely discussed in sport.
But the recent interest in the subject has also created a new simplification: strength, endurance and high-intensity sessions are now sometimes prescribed according to a precise sequence of hormonal phases.
It is easy to find calendars recommending more strength work in the follicular phase, very intense sessions around ovulation and reduced training load in the luteal phase.
The problem is that the evidence is far less clear-cut.
A cycle is not necessarily a 28-day calendar
The first problem with very simple models is the way they represent the cycle itself. A menstrual cycle does not necessarily last 28 days, and its different phases do not always occupy the same number of days.
The first half of the cycle in particular can vary substantially between women and from one cycle to the next. Predicting ovulation precisely from the day number alone is therefore much less reliable than a neat diagram may suggest.
A recommendation such as “put your hardest session on day 14” already depends on an assumption that may simply be wrong for the athlete in question.
What does the research actually say about performance?
In 2020, Kelly McNulty and colleagues published a major systematic review and meta-analysis on the effects of menstrual-cycle phase on physical performance.
On average, they found a possible very small reduction in performance during the early follicular phase, around the start of menstruation.
But the effect was trivial, results varied greatly between studies and the overall quality of the evidence was low.
Their practical conclusion matters: the available data do not support general training recommendations based on menstrual-cycle phase. An individualised approach is more appropriate [1].
In other words, there is currently no strong enough basis to say that every female runner should do VO₂ work in one phase, strength work in another and recovery work in a third.
Symptoms are often more useful than the name of the phase
Saying that average effects are small does not mean the cycle has no effect in real life.
Some women notice almost no difference across the month. Others regularly experience pain, fatigue, digestive symptoms, mood changes, migraines or disrupted sleep.
In a large study of physically active women, menstrual symptoms were frequently associated with modifying or missing training [2].
That distinction is crucial.
At group level, the average effect of a hormonal phase on performance may be very small. At individual level, an athlete may still have two days of significant pain at the start of every period and be clearly less ready for a demanding session.
A coach does not need a complicated hormonal theory to take that into account.
Heavy menstrual bleeding: still discussed far too little
Among the symptoms that can genuinely affect training, heavy menstrual bleeding deserves particular attention. It can still be difficult to discuss with a coach, especially a male coach, even though the practical consequences can be very real.
For an athlete, the issue is not limited to discomfort. Heavy bleeding can complicate a long run, a competition, travel or simply access to menstrual products during training. Fear of leakage can also become a source of concern during exercise.
Menstrual blood loss can also contribute to iron deficiency. In a runner with heavy periods and unusual fatigue, new shortness of breath, a persistent drop in performance or abnormally difficult recovery, it is important not to assume too quickly that the problem is simply training.
Periods lasting more than seven days or requiring very frequent changes of menstrual products may be reasons to discuss the issue with a healthcare professional. The coach’s role is not to determine the cause or prescribe iron, but to recognise that the issue may go beyond training programming.
In athlete monitoring, situations like this also highlight something simple: the athlete needs to feel comfortable enough to talk about it in the first place. Normalising conversations around menstruation is part of the job, without ever requiring an athlete to share information she would prefer to keep private.
Adapt to symptoms rather than to a calendar
In practice, I prefer to start with the planned session and the athlete’s actual condition that day.
If she feels normal and has no troublesome symptoms, there is no automatic reason to change the session simply because she is on a particular day of her cycle.
If symptoms clearly affect the session, several adjustments are possible: reduce the number of repetitions, slightly increase recovery, move a demanding workout or simply replace intensity with an easy session.
These are exactly the same principles we use when poor sleep, a difficult work week or unusual fatigue temporarily reduce the ability to absorb training.
The difference is that some menstrual symptoms can recur. When a pattern appears across several cycles, it can then become something worth anticipating.
What is worth tracking?
Tracking the cycle can therefore be useful, but not necessarily to predict hormones or automatically programme training.
A few simple pieces of information can already be valuable:
- the first day of menstruation;
- approximate cycle length;
- symptoms that genuinely affect daily life or training;
- sleep and fatigue when they seem linked to particular times;
- perceived effort in familiar sessions;
- any major irregularities.
The goal is not to collect intimate data for the sake of it. It is to understand whether something repeats often enough to justify a training decision.
Recent work on menstrual health also emphasises improving cycle literacy among athletes and the people around them rather than turning menstrual data into automatic prescriptions [3,4].
A bad session is not necessarily hormonal
The opposite bias also needs to be avoided.
When an athlete has a difficult session during her period or at another point in the cycle, it becomes tempting to explain the performance immediately through hormones.
But a poor night’s sleep, inadequate fuelling, a high training load, heat, stress or simply normal performance variability can create exactly the same feeling.
Cycle tracking should provide one additional piece of information. It should not become the default explanation for everything that happens to an athlete.
What about hormonal contraception?
The situation is different again for women using hormonal contraception.
With a combined oral contraceptive, for example, hormonal variation is not the same as in a natural menstrual cycle. Bleeding during the pill-free interval or placebo tablets is withdrawal bleeding and does not correspond to menstruation produced by a typical ovulatory cycle.
A meta-analysis on oral contraceptives and performance again suggests that average differences are generally small and probably of little practical relevance for most athletes [5].
That does not mean individual women never notice effects. But once again, observing the athlete’s actual response is more useful than applying a general rule.
The cycle is also a health marker
Talking about the menstrual cycle only to decide where to place an interval session would miss an important part of the picture.
In an athlete who previously had regular cycles, periods that become very infrequent or disappear should not automatically be treated as a normal consequence of training.
One possible cause is low energy availability: energy intake is no longer sufficient to cover both training demands and normal physiological function.
Menstrual disturbances are therefore among the factors considered in Relative Energy Deficiency in Sport (REDs) [6].
A prolonged absence of periods or a major unexplained change in the cycle deserves discussion with a healthcare professional rather than simply an adjustment to the training plan.
Should you talk about your cycle with your coach?
Only if you want to.
A coach does not need every detail of an athlete’s cycle. But the athlete should be able to say that a particular time regularly causes problems without the subject being awkward or dismissed.
For some athletes, “I’m on my period and I’m in a lot of pain today” will be enough information to make a training decision.
For others, a few months of monitoring may reveal a recurring pattern.
And for many, no specific change will be needed at all.
The cycle changes across a lifetime too
What an athlete experiences at 25 will not necessarily be what she experiences at 40 or 50.
As perimenopause approaches, cycles can become more irregular and hormonal fluctuations less predictable. Building training around a theoretical calendar then becomes even less relevant.
We discuss this period in a dedicated article on menopause and training .
In practice
I would not build a runner’s training around a theoretical hormonal calendar. I would start by programming what she needs for her goal, then look at whether certain symptoms or difficulties repeat often enough to justify an adjustment.
For some women, the cycle will regularly affect certain sessions. For others, almost never. Both situations are normal.
What to take away
Taking the menstrual cycle into account does not necessarily mean training “according to your cycle”.
Current evidence does not support prescribing particular sessions to particular phases as a general rule. It supports a more individualised approach based on symptoms, the athlete’s history and her actual response to training.
That is less eye-catching than a four-colour 28-day calendar. But it is far more useful when coaching a real person.
Further reading
- Menopause and training: do you really need to change the way you train?
- Running after 40: how to keep improving
Need a coach?
Oregano Athletics works primarily with women and masters athletes, from a first time-based goal through to performance-focused training.
See our coaching and get in touch .
References
- McNulty KL, Elliott-Sale KJ, Dolan E, et al. The Effects of Menstrual Cycle Phase on Exercise Performance in Eumenorrheic Women: A Systematic Review and Meta-Analysis. Sports Medicine. 2020;50:1813–1827. DOI: 10.1007/s40279-020-01319-3.
- Bruinvels G, Goldsmith E, Blagrove R, et al. Prevalence and frequency of menstrual cycle symptoms are associated with availability to train and compete: a study of 6812 exercising women recruited using the Strava exercise app. British Journal of Sports Medicine. 2021;55:438–443.
- McGawley K, Sargent D, Noordhof D, et al. Improving menstrual health literacy in sport. Journal of Science and Medicine in Sport. 2023;26(7):351–357. DOI: 10.1016/j.jsams.2023.06.007.
- Badenhorst CE. The Menstrual Health Manager: A Resource to Reduce Discrepancies Between Science and Practice in Sport and Exercise. Sports Medicine. 2024;54:2725–2741. DOI: 10.1007/s40279-024-02061-w.
- Elliott-Sale KJ, McNulty KL, Ansdell P, et al. The Effects of Oral Contraceptives on Exercise Performance in Women: A Systematic Review and Meta-analysis. Sports Medicine. 2020;50:1785–1812. DOI: 10.1007/s40279-020-01317-5.
- Mountjoy M, Ackerman KE, Bailey DM, et al. 2023 International Olympic Committee’s consensus statement on Relative Energy Deficiency in Sport (REDs). British Journal of Sports Medicine. 2023;57:1073–1097.