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Training in the luteal phase without writing the week off

By Chris Ayers 6 min read

The luteal phase is the stretch between ovulation and your next period. In a 28-day example the Cleveland Clinic puts it at days 15 to 28, the time when “the level of the hormone progesterone rises to help prepare your uterine lining for pregnancy.” Real cycles are less tidy than the example. A 2019 paper in npj Digital Medicine looked at 612,613 cycles and found a mean luteal phase of 12.4 days, with most falling between 7 and 17 days.

So, roughly two weeks. If you lift three or four times a week, that is six to eight sessions. Writing them off because a post somewhere told you the luteal phase is a bad time to train would cost you close to half your training year.

Here is what the research has actually measured, and what it has not.

Some things do change

Two things change. The first is resting heart rate, and a sensor can pick it up. A 2017 study in Scientific Reports put a wrist sensor on 91 women across 274 cycles and measured pulse during sleep. Mid-luteal pulse was 3.8 beats per minute above the menstrual phase, and 1.8 beats above the fertile window. Small, and it held up after the researchers adjusted for daily habits and diet.

The second is sleep, and here the evidence is weaker. The FENDURA project, published in the Journal of Sports Sciences in 2025, followed 58 endurance athletes for a full year. Perceived sleep quality was lower in the days before bleeding than on bleeding days, and symptom severity was highest on the bleeding days themselves. Worse symptoms went with worse sleep and lower readiness to train. Note what that is: self-reported sleep, in endurance athletes, not lifters, and the comparison was the days just before bleeding against bleeding days, not the luteal phase as a whole.

If you wear a watch or a ring to bed, this is the part of the month when your recovery numbers can look a shade worse for no reason you can name. Now you have a name for it.

The strength data does not say stop

This is the part I care about most, because it is where the app lives.

A big review of exercise performance across the cycle came out in Sports Medicine in 2020. It covered 78 studies, with 51 in the main meta-analysis. Its finding was that performance “might be trivially reduced during the early follicular phase,” meaning the first days of your period, compared with all other phases. Trivially. The luteal phase was not singled out as a low point at all. The authors rated the quality of the evidence as low and wrote that “general guidelines on exercise performance across the MC cannot be formed; rather, it is recommended that a personalised approach should be taken based on each individual’s response.”

That is 51 studies pooled together. It finds no meaningful luteal penalty on performance and it tells you to go by your own response. It does not tell you to rest for two weeks.

What “adjust by how you feel” looks like

I am not a coach, and I am not going to hand you a program. What I can tell you is how the app treats these two weeks, and why.

When you are in your luteal phase, the Today screen in Ferrabelle reads: “You are in your luteal phase, when the body gradually winds down toward your period. Steady effort and good fuel keep you feeling level.” The word is steady, not stop.

In practice that comes down to a few plain moves.

The Fe Score folds your phase, your sleep, your stress and your recovery into one number each morning. When the sleep and recovery inputs dip, the score dips with them. That is what it is for. It is a nudge about effort for the day, not a stop sign over the phase.

Where the evidence is thin

Most of the strength studies are small, and a 2023 umbrella review in Frontiers in Sports and Active Living found “a pattern of poor and inconsistent methodological practices in the literature,” often because cycle phase was never verified with a hormone test. The sleep finding comes from one sport and one year. I have not found a large trial that followed trained women lifting through the luteal phase for months to see what happens to progress. That is why “adjust by how you feel” is the honest reading of what we have, and why the app asks how each session felt.

I built Ferrabelle to learn my wife’s cycle and her barbell, not a chart’s average. If your luteal sessions are fine, the log will say so, and you can stop apologizing for them.

This is general information, not medical advice. Talk to your doctor about your own health.

Ferrabelle is in a closed test on Google Play right now. If you want to try it, you can join at ferrabelle.com/testers.

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