An outbreak of 49 cases of tinea corporis gladiatorum due to Trichophyton tonsurans infection occurred in a high level judo team of 131 members in Orleans, central France, between October 2004 and April 2005. The team was divided into 5 groups: cadet-junior boys (n=44), cadet-junior girls (n=33), male university students (n= 15), female university students (n=21), and a group called 'pole technique' made up of high level judokas who have finished academic study (n=18). The outbreak involved 86% of the cadet-junior boys, but only 6 men in the 'pole technique' (33%) and only 5 of the 69 other team members (7%) (cadet-junior girls and university students). We describe the outbreak and the results of a survey that found a known risk factor for the 'pole technique': sharing an electric hair shaver. Personal hygiene practices were found to be very good among the cadet-junior boys. The high attack rate in this group may be linked to the poor shower facilities in the gymnasium where they practiced that led them to have their showers several hours after the end of daily practice.