Most fasting advice was written for men
Your hormones move on a roughly four-week cycle, and what your body can handle moves with them. FastFemale is an 8-week cohort and a companion app that adapt your fasting window, your fuelling and your training to the phase you are actually in.
One body, four different weeks
The same protocol lands differently depending on where you are in your cycle. These four phases arrive in order, and FastFemale changes its guidance as you move through them.
Menstrual
Energy is usually at its lowest. Shorter fasts, more rest, and training that restores rather than depletes.
Follicular
Rising oestrogen tends to bring capacity back. The week where longer fasts and harder sessions are most likely to feel good.
Ovulatory
Typically your strongest window. Peak output, and the best time to test what you are capable of.
Luteal
Appetite and core temperature climb. Fasting hard here is where most women stall, so the plan eases off instead.
The whole month in one picture
Fasting window and training intensity, drawn around the four phases. It is the shape the plan follows, and the shape the app is reading from when it tells you what today asks of you.
- Menstrual Days 1 to 5
- Lowest capacity. Shorter fasts, restorative training.
- Follicular Days 6 to 13
- Capacity climbing. Longer fasts start to feel easy.
- Ovulatory Days 14 to 16
- Peak output. The week to test what you can do.
- Luteal Days 17 to 28
- Appetite and temperature up. Where most plans stall.
What actually changes
Three levers, adjusted week by week rather than set once and defended forever.
Your fasting window
Target hours that move with your phase, instead of a fixed 16:8 you white-knuckle through the weeks it does not suit.
How you fuel
Phase-aware guidance on what to eat and when, particularly through the luteal week, where under-fuelling does the most damage.
How hard you train
Session intensity modulated by phase, so the hard weeks land when your body can absorb them and recovery is planned, not improvised.
Cohort 1 is small, guided, and starting in October
- 8 weeks
- A guided curriculum, start to finish
- 15–20
- Women per cohort, so you are not a row in a spreadsheet
- October
- Cohort 1 begins; the waitlist opens first
Why a cohort, not just an app
An app can tell you what phase you are in. It cannot talk you out of quitting in week three, and it cannot answer the question you did not know to ask.
So the cohort is the programme, and the app is what you use between sessions. Eight weeks of structured curriculum, run live with a small group, with guest experts joining for the topics that deserve a specialist. You log your cycle, fasts and training in the app; the group is where you work out what the numbers mean for you.
The curriculum is assembled from the published work of practitioners including Mindy Pelz, Stacy Sims and Alisa Vitti, with sources cited so you can read the originals yourself. FastFemale is education, not medical advice. Nothing here diagnoses, treats, or replaces care from your own clinician.
Questions people ask first
Do I need to have fasted before?
No. The curriculum starts from first principles. It is equally useful if you have fasted for years and hit a plateau. That plateau is often the point where a male-default protocol runs out of road.
Is the app free?
Yes. The app is free, and access is currently by invitation while we work with the first cohorts.
Is this medical advice?
No. FastFemale is education, not medical advice. Nothing here diagnoses, treats, or replaces care from your own clinician. If you are pregnant, breastfeeding, managing an eating disorder, or living with a condition affected by fasting, talk to your clinician before joining.
What if my cycle is irregular, or I do not have one?
Come anyway, and tell us in your waitlist note. Irregular cycles, hormonal contraception and perimenopause all change how the guidance applies, and that is worth handling directly rather than pretending a generic plan fits.
When does Cohort 1 start?
October 2026. The waitlist opens ahead of it, and waitlist members hear about dates and joining details first.
Cohort 1 starts in October
Fifteen to twenty women, eight weeks, one cycle-aware plan. Join the waitlist and you will hear first.
Ask us anything
Questions about the cohort, the app, or whether this fits your situation. A person reads these.