TY - JOUR T1 - Decrease in body fat during an ultra-endurance triathlon is associated with race intensity JF - British Journal of Sports Medicine JO - Br J Sports Med SP - 609 LP - 613 DO - 10.1136/bjsm.2007.040956 VL - 42 IS - 7 AU - B Knechtlet AU - M Schwanke AU - P Knechtle AU - G Kohler Y1 - 2008/07/01 UR - http://bjsm.bmj.com/content/42/7/609.abstract N2 - Objective: To investigate whether adipose subcutaneous tissue or skeletal muscle mass decreased during a non-stop ultra-endurance triathlon. Design: Descriptive field study. Setting: The Triple Iron Triathlon Germany 2006 in Lensahn: 11.6 km swimming, 540 km cycling and 126.6 km running. Subjects: 17 male Caucasian triathletes, mean (SD) age 39.2 (7.5) years, height 178 (5) cm, body mass 80.7 (8.9) kg and body mass index (BMI) 25.4 (2.4) kg/m2. Interventions: None. Main outcome measurements: Determination of body mass, skin-fold thicknesses, limb circumference, skeletal muscle mass and percentage body fat in order to show changes after the race. Results: A significant decrease was shown for body mass (p<0.001), BMI (p<0.001) and calculated percentage body fat (p<0.001) whereas skeletal muscle mass did not change significantly (p>0.05). Circumferences of the thigh, upper arm and calf did not decrease significantly (p>0.05), whereas all skin-fold thicknesses decreased significantly (p<0.05), with the exception of those at the chest and thigh. A significant correlation was found between the loss of percentage body fat and the loss of body mass (p<0.01, r2 = 0.55) as well as change in percentage body fat with race performance (p<0.05, r2 = 0.24). Conclusions: Ultra-endurance triathletes at the Triple Iron Triathlon Germany 2006 showed a significant decrease in body mass and percentage body fat, where decrease in percentage body fat was associated with race intensity. ER -