Take2 weeks ago
Garmin and TrainingPeaks now let riders log cycle data straight into their training dashboards, and coaches are told it's a "super power." A recent power-output study found no significant difference between early follicular and mid-luteal phases — the exact split the tracking narrative is built on.
Cycling has no agreed methodology here: one clustering study of 81 full cycles found intensity index 8% higher mid-cycle, while a separate submaximal-ride study found no significant power differences by phase at all. The field itself admits general cycle-based periodization advice can't be given yet. What the data does support consistently is the health side — professional riders regularly show cycle disorders tied to RED-S, with real long-term risk to bone density and cardiovascular health. That's a harder sell than a performance hack, which may be why it's not what's driving app adoption.
Sources
The Impact of Menstrual Cycle Phase on the Power Profile of Female Cyclists During a Standardised Submaximal Training RideImpact of menstrual cycle or combined oral contraception on elite female cyclists' training responses through a clustering analysis of training sessionsCycling Through the Menstrual CycleHow Menstrual Cycle Tracking Can Revolutionize Female Athlete Training