How do you track your menstrual cycle?
At its simplest, you log the first day of every period, which marks the start of a new cycle, and your cycle length is the number of days from one period start to the next. Track for two to three months and patterns emerge: your typical cycle length, how much it varies, and when symptoms tend to land. You can track on paper or a calendar, but an app does the counting and pattern-spotting for you.
What to log (and what is worth the effort)
Start with the essentials, then add what is useful to you:
- Period start and end. The non-negotiable. Everything else anchors to this.
- Flow. Light, medium, or heavy, which matters for spotting changes and iron.
- Symptoms. Cramps, mood, sleep, energy, headaches. This is where the real insight lives.
- How you feel day to day. A quick read on energy and soreness turns tracking from a record into a decision tool.
Resist the urge to log everything at once. A few fields you actually fill in beat twenty you abandon after a week.
Why track your cycle at all?
Three reasons. First, it makes the invisible visible: the low mood or flat run that felt random turns out to track with your cycle. Second, it is the best evidence you can bring to a doctor, especially if you suspect perimenopause, where there is no single confirming test and the pattern over time is the diagnosis. Third, if you train, your cycle phase changes how you should run and lift. See the four cycle phases.
How to track an irregular cycle
Irregular cycles are exactly the ones worth tracking, because the pattern is not obvious from memory. Keep logging period starts even when they are unpredictable, and lean more on the daily how-you-feel read, which still works when the calendar does not. See irregular periods.
A note on accuracy: predictions are estimates based on your history, not guarantees, and they should not be relied on as contraception or to time conception without a method built for that. Tracking shows patterns, it does not control your body. Phaes is informational, not medical advice.
From tracking to doing
A chart is the start, not the point. Most apps log your cycle and hand you a graph. Phaes takes the same logging and a daily check-in and turns it into a running and strength plan that adapts: it anchors to your real cycle, biases hard work toward the windows you build best, and eases off when you are depleted. See a period tracker for runners, cycle syncing workouts, or take the 2-minute quiz.