Hairbrush Screening in 902 Tokyo University Judo Athletes

November 12, 2026

Doctor’s Notes · Life in Motion · Evidence Review

Editorial disclosure: The featured image is an AI-created illustration of a fictional activity, training or occupational setting. It is not a patient, diagnosis, before-and-after image, institutional endorsement or Dr. Arsy #003 treatment result.

Reader question: What did this exact study measure, in whom, with which comparator and timepoint—and which conclusions would go beyond its evidence?

Study snapshot

Study element	Reported detail
Population	902 athletes from judo clubs at 21 First Division universities in the University Judo Federation of Tokyo.
Design	Cross-sectional questionnaire and scalp hairbrush-culture screening with treatment recommendations and repeat culture.
Comparator	Culture-positive versus culture-negative athletes; culture status before versus three months after treatment recommendations.
Timepoint	Initial 2008 screening and repeat hairbrush testing three months after treatment.
Key result	102 of 902 athletes (11.3%) had positive cultures; 14 of the 102 had tinea corporis and the remainder were asymptomatic. Of 96 culture-positive athletes retested, 85 converted to negative culture.
Funding/conflict context	Funding and author-conflict details were not reported in the accessible PubMed abstract.

What was actually measured?

102 of 902 athletes (11.3%) had positive cultures; 14 of the 102 had tinea corporis and the remainder were asymptomatic. Of 96 culture-positive athletes retested, 85 converted to negative culture.

The study separates visible disease from asymptomatic carriage and reports a concrete post-recommendation conversion denominator. Without an untreated group, conversion cannot be attributed solely to any one element of the program.

The denominator defines the claim. People, visits, infections, episodes, isolates, feet and blisters are different analytic units. A percentage or rate using one unit cannot be silently rewritten as the percentage of people affected.

What the result does not prove

Participation was limited to registered university clubs, treatment was recommended rather than randomized, and six culture-positive athletes lacked the reported repeat-test denominator.

Association and timing do not automatically prove individual causation. Footwear, surfaces, climate, ultraviolet exposure, hygiene, protective equipment, training load, prior conditions, referral patterns and access to care may change an estimate.

A PubMed record is a bibliographic source. PubMed indexing is not NIH endorsement of the authors’ conclusions, this interpretation or any product.

Infection boundary: Moisturization does not eradicate fungi or bacteria, replace culture or other diagnostic testing, or substitute for infection-control and medical treatment.

Keep the condition categories separate

Dryness, friction injury, sunburn, dermatitis, sensitization, fungal disease and bacterial infection are not interchangeable. A moisturizer may support hydration and the moisture barrier, but it does not diagnose infection, prevent ultraviolet injury, replace medical evaluation or substitute for activity-specific prevention.

Persistent spreading redness, drainage, fever, severe pain, rapidly worsening symptoms, a suspected contagious outbreak or major loss of function warrants prompt professional assessment. Clinicians may need microscopy, culture, patch testing, skin-prick testing or other targeted evaluation depending on the question.

Activity details worth documenting

What surface, footwear, sock, glove, mat, pool, boat, uniform, animal, climate or training load preceded the change?
Where did the problem begin, and did it change during rest, travel, deployment, competition or a different facility?
Were towels, clothing, footwear, razors, equipment or showers shared, and how were high-touch surfaces cleaned?
How often was skin wet, occluded, rubbed, heated, chilled or exposed to sun?
Did the problem alter sleep, pace, attendance, training, competition, work safety or duty status?

Prevention comes before cosmetic care

Prevention should match the hazard: well-fitted and broken-in equipment, task-appropriate textiles, friction management, clean personal gear, facility hygiene, prompt showering, ultraviolet protection and timely clinical assessment. No single intervention prevents every diagnosis.

Do not share personal skin products during an outbreak and do not test workplace, sport or environmental materials directly on skin. Follow occupational-health, sports-medicine, public-health and facility instructions for contagious or exposure-related conditions.

Primary research and authoritative guidance

Where Dr. Arsy #003 fits

Dr. Arsy #003 is a cosmetic moisturizer for hydration, moisture-barrier support and dry-skin comfort. This study did not test #003. Its findings do not show that #003 treats, cures or prevents eczema, infection, blisters, sunburn or sensitization; relieves pain or itch; neutralizes environmental exposures; is appropriate for every person; or provides pediatric or 24-hour efficacy.

Continue the evidence series

Evidence note: This educational article separates reported findings from interpretation. It is not a diagnosis, treatment recommendation or workplace, sports, military, maritime, animal-exposure or infection-control determination.

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