Intake of supplements such as vitamins and minerals is widespread in athletes. The aim of the study was the investigation of the influence of intake of vitamins and minerals before an ultra-endurance triathlon and its effect on race performance in a descriptive field study. Participants of the “Triple Iron Triathlon Germany 2006“ in Lensahn, Schleswig-Holstein, Germany, were contacted by a newsletter six weeks before the race by the organizer and received a questionnaire to fill in their intake of vitamins and minerals. Questionnaires were self-administered and not administered by trained personnel. During this race the athletes had to cover 11.4 km swimming, 540 km cycling and 126.6 km running within 58 hours. The athletes were divided into two categories: successful finishers with intake of vitamins and minerals and successful finishers without intake prior to the race. Race performance (total running time in h) of athletes with intake and athletes without intake of these substances was compared. In the four-week period prior to the race,
nine athletes (53 %) ingested vitamins and eight athletes (47 %) minerals. Athletes with intake of vitamins
(44.7 ± 7.0 h versus 50.4 ± 4.4h; p>0.05) and minerals (45.3 ± 7.2 versus 49.3 ± 5.4 h, p>0.05) finished the
race not faster than athletes without intake of vitamins and minerals. In the “Triple Iron Triathlon Germany 2006“ in Lensahn, Germany, no influence on race performance was observed concerning the regular intake of vitamins and minerals in the last four weeks before the race.