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Experts warn that popular ‘cycle-syncing’ workouts lack solid scientific backing

Fitness influencers promote workout plans tied to menstrual phases, but researchers say the practice is not supported by robust evidence and recommend a more individualized approach.

A surge of social-media posts, many tagged #cyclesyncing, advise women to align their workouts with menstrual phases, recommending gentler activity during periods and higher-intensity training around ovulation. Researchers, including Kelly McNulty of Leeds Beckett University, acknowledge that some women experience fluctuating symptoms but stress that no studies validate a one-size-fits-all regimen. The variability of cycle length and the influence of contraception make blanket recommendations unreliable.

Practitioners such as nurse-trainer Cesci Burgoyne and fitness creator Sarah Mackay prefer intuitive adjustments based on how they feel, while Dr. Faye Bate warns that prescribing reduced effort could create a nocebo effect and hinder strength gains. Experts agree that tracking one’s own cycle can be useful, but the focus should be on personal cues rather than strict phase-based rules.

Why it matters

Understanding the limits of cycle-syncing helps women avoid unfounded restrictions and maintain effective, personalized fitness routines.

In this story

cycle syncingmenstrual cycleworkout planningnocebo effectstrength trainingfitness influencersindividual variation
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