Scientific stance: recent systematic reviews (McNulty 2020) suggest individual variation is larger than group-level menstrual-cycle patterns. This tool offers personalized micro-adjustments anchored to your own baseline, with body signals first.
Cycle Data
First day of most recent period
Average cycle length (days)
Period duration (days)
Premenstrual symptoms (personalized interpretation)
Cramp comfort (5 = no issue): 4/5
PMS mood impact (5 = no issue): 4/5
Sleep quality impact (5 = no issue): 4/5
Why micro-adjust instead of completely changing training?
McNulty et al. (2020) reviewed 78 studies and found:
• Early follicular performance may be slightly lower
• Effect sizes are small (<5%) and individual variation is much larger than group effects
• Perceived readiness matters more than theory. If you feel good during your period, train normally; if you feel poor, reduce load.
McNulty et al. (2020) reviewed 78 studies and found:
• Early follicular performance may be slightly lower
• Effect sizes are small (<5%) and individual variation is much larger than group effects
• Perceived readiness matters more than theory. If you feel good during your period, train normally; if you feel poor, reduce load.
Fill in your cycle data and recommendations will appear here
Evidence
- McNulty et al. (2020): Sports Medicine systematic review of 78 studies found early follicular performance may be slightly lower, but effects are small (<5%) and individual variation is much larger.
- Carmichael et al. (2021): Int J Environ Res Public Health reviewed metabolic changes and practical fueling adjustments across phases.
- Sims & Yeager (2024): ROAR emphasizes individual tracking and finding your own fast and slow phases over at least 3 months.
- Ackerman et al. (2019): RED-S warning: excess training plus low energy availability can disrupt menstruation and should be treated as a key signal.
Warning signs: no period for ≥3 consecutive months, frequent cycles shorter than 21 days, or very low flow should prompt medical evaluation; RED-S or hormonal issues may be involved.