Menstrual-Cycle Tracking

For menstruating individuals, the menstrual cycle is a recurring physiological variable worth logging because it predictably affects several tracked metrics. A typical cycle is about 28 days (commonly 21–35 is considered normal), divided broadly into the follicular phase (from menstruation to ovulation) and the luteal phase (after ovulation to the next period).

What to log: period start/end dates, cycle length, and symptom ratings (cramps, energy, mood, sleep, appetite, soreness). From start dates the app can estimate the current phase and overlay it on other metrics.

Why it matters for tracking:

• Weight fluctuations. Water retention often rises premenstrually and during the luteal phase, so scale upticks there are typically water, not fat (see Interpreting Weight Fluctuations).
• Readiness signals. Mood, energy, sleep, and soreness ratings (see Subjective Readiness Ratings (Mood / Energy / Soreness)) and resting metrics like Heart-Rate Variability (HRV) can shift across phases, so interpreting them against the cycle prevents false alarms.
• Training context. Some find strength/energy feels higher in parts of the cycle and lower premenstrually; tracking lets the individual spot their own pattern. Evidence for rigidly periodizing training to cycle phase is mixed, so treat this as individualized information, not a prescription (see Considerations by Sex (Where Evidence-Based)).

Privacy note: cycle/reproductive data is sensitive; handle it under the same data-privacy care as all health data (see Health-Data Privacy Basics).

• Typical cycle ~28 days (≈21–35 normal); follicular and luteal phases.
• Log period dates, cycle length, and symptom ratings.
• Luteal/premenstrual water retention explains predictable scale upticks.
• Phase can shift HRV, sleep, mood, and energy — interpret metrics against it.
• Cycle-phase training periodization evidence is mixed; individualize, don't prescribe.