The Centre should take women’s experiences seriously without turning every trend, testimonial or commercial claim into medical fact. WC-08 gives players, parents, coaches and clubs simple ways to ask: What exactly is being claimed? What evidence supports it? Who does it apply to? What is uncertain? Who benefits commercially if I believe it?
TAKE WOMEN’S EXPERIENCES SERIOUSLY — WITHOUT TURNING EVERY TREND INTO MEDICAL FACT.
Our six evidence labels
Established guidance
Current authoritative guidance supports the statement.
Supported but individual
Evidence supports the issue, but individual experience or application varies.
Emerging evidence
Promising or developing evidence that is not yet strong enough for a universal rule.
Mixed / uncertain
Evidence is inconsistent, limited or too heterogeneous for a confident conclusion.
Not supported
The claim is not adequately supported by reliable evidence or conflicts with stronger evidence.
Lived experience
A person’s own account. Important, but not presented as clinical proof.
The evidence test
- Define the exact claim. Avoid vague wording such as “balances hormones”.
- Find the original source. Trace headlines, influencer posts and company claims back to the underlying guidance or study.
- Check the population. Evidence in a particular sport, age or clinical group must not be silently generalised to every woman.
- Check the size and certainty of the effect. Statistical difference is not automatically a meaningful practical effect.
- Look for limitations and disagreement. Do not edit uncertainty out of the public version.
- Check commercial interest. A sponsor, affiliate link or product sale does not automatically make a claim false, but the relationship matters.
- Ask what could happen if somebody acts on it. Medication, diet, supplements, healthcare, anti-doping and safeguarding claims need a higher threshold.
Cycle syncing
Current evidence does not justify a universal four-phase training prescription for all women. A 2020 systematic review/meta-analysis found at most a trivial average performance reduction in the early follicular phase, with low-quality and highly variable evidence, and recommended an individualised approach rather than general phase-based performance rules. A 2026 repeated-measures study in 20 trained women found no meaningful phase differences in the measured performance, recovery or sleep outcomes despite large hormone fluctuations.
Centre rule: BE CYCLE-AWARE — NOT CYCLE-PRESCRIPTIVE. Symptoms can matter to an individual athlete; that is different from claiming a calendar phase predicts performance for everybody.
Health products and commercial claims
Supplements, hormone products, tests and “female athlete” products should be assessed on the exact claim, regulatory status, evidence, safety and commercial context. UKAD states that no supplement can be guaranteed free from prohibited substances and that WADA/UKAD do not approve or certify supplements. ASA/CAP rules also place strict limits on health and medicinal claims in advertising, including prohibiting food and supplement claims that treat, prevent or cure human disease.
SELLING A SOLUTION DOES NOT PROVE THE PROBLEM — OR THE SOLUTION.
Social media
A viral post can be useful for raising a question. It is not a clinical guideline. Warning signs include universal claims, fear and urgency, “doctors don’t want you to know”, vague hormone reset language, diagnosis by generic quiz, testimonials used as proof, “natural means safe”, instructions to stop medication, and undisclosed commercial relationships.
AI and evidence
AI can help organise questions, draft plain-language explanations and identify sources to check. It is not itself a medical evidence source. Material factual claims must be verified against real, retrievable sources, and no citation should remain on the Centre if it cannot be opened and shown to support the claim.
Phase 1 resources and review status
- WC-08A — How to Check a Women’s Health Claim
- Under additional review
- Under additional review
- WC-08D — Social Media Health Advice: Red Flags
- WC-08E — How Eights and Arrows Checks Evidence
Key sources checked for WC-08
- NICE — How NICE guidelines are developed
- McNulty et al. — menstrual-cycle phase and exercise performance systematic review/meta-analysis
- Pearson et al. 2026 — repeated-measures menstrual-cycle study
- UK Anti-Doping — Managing Supplement Risks
- ASA/CAP — Recognising social-media advertising
- ASA/CAP — Food disease prevention and treatment claims
- MHRA — Borderline products and medicines
- NHS — Herbal medicines and complementary therapies
These are key sources, not the complete internal evidence register. Source currency and jurisdiction must be rechecked immediately before publication.
Important boundary
WC-08 is evidence-literacy and governance material. It does not diagnose an individual, interpret tests, prescribe or change medication, provide individual diets or supplement regimes, or give medical clearance. Commercial partnerships do not change this boundary.