We investigated the timeline of performances in the three races of the 'World Challenge Deca Iron Triathlon', held in 2006, 2007 and 2009, where the athletes completed one Ironman triathlon daily on 10 consecutive days. The association of anthropometric characteristics such as body fat estimated using bioelectrical impedance analysis and previous experience in ultra-triathlon with race time was investigated using multiple linear regression analysis. Forty-nine athletes participated in these three races; 23 (47%) participants completed the race within 8,817 (1,322) min. Day 1 was the fastest with 762 (86) min; the slowest was Day 10 with 943 (167) min (P<0.05). The time per Ironman increased during the race (P<0.05). Body mass and fat mass decreased whereas lean body mass increased (P<0.05). Race time was related to both the number of finished Triple Iron triathlons (P=0.028) and the personal best time in a Triple Iron triathlon (P<0.0001). We concluded that performance in a Deca Iron triathlon decreased throughout the competition, with the fastest race on Day 1 and the slowest on Day 10. The number of finished Triple Iron triathlons and the personal best time in a Triple Iron triathlon, but not anthropometry, were related to race time. To conclude, athletes need to have a high number of previously completed Triple Iron triathlons, as well as a fast personal best time in a Triple Iron triathlon, in order to finish a Deca Iron triathlon successfully.

Objective:To investigate the association of anthropometric parameters to race performance in ultra-endurance runners in a multistage ultra-endurance run.Design:Descriptive field study.Setting:The Deutschlandlauf 2006 race in Germany, where athletes had to run 1200 km within 17 consecutive days. There were no interventions.Subjects:In total, there were 19 male Caucasian ultra-endurancerunners (mean (SD) 46.2 (9.6) years, 71.8 (5.2) kg, 179 (6) cm, BMI 22.5 (1.9) kg/m2).Main outcome measurements:Determination of body mass, body height, length of lower limbs, skin-fold thicknesses, circumference of limbs, body mass index (BMI), percentage skeletal muscle mass (%SM), and percentage body fat (%BF) in 19 successful finishers in order to correlate anthropometric parameters with running performance.Results:A significant association of upper arm circumference with the total running time was found (p<0.05, r2 = 0.26). No significant association was found with the directly measured anthropometric properties body height, body mass, average skin-fold thickness and the circumference of thigh and calf (p>0.05). Furthermore, no significant association was observed between the running time and the calculated parameters BMI, %BF, and %SM (p>0.05).Conclusions:In an ultra-endurance run over 1200 km within 17 consecutive days, circumference of the upper arm was the only factor associated with performance in well-experienced ultra-endurance runners. Body mass, BMI, body height, length of limbs, skin-fold thicknesses, circumference of limbs and the calculated percentage body composition of skeletal muscle mass and body fat showed no association with running performance.

In the present study, we investigated the association of anthropometric parameters with race performance in ultraendurance runners in a multistage ultraendurance run, in which athletes had to run 338 km within 5 consectitive days. In 17 male successful finishers, calculations of body mass, body height, skinfold thicknesses, extremity circumference, skeletal muscle mass (SM), and percentage body fat (%BF) were performed before the race to correlate anthropometric parameters with race performance. A positive association was shown between total running time and both body mass (r2 = .29, p < .05) and upper arm circumference (r = .23, p < .05). In contrast, body height, skinfold thicknesses, extremity circumference, SM, and %BF showed no association with race performance (p > .05). We concluded that in a multistage ultraendurance run, body mass and upper arm circumference were nega tively associated with race performance in well experienced ultraendurance runners. In contrast, body height, skinfold thicknesses, circumferences of the other extremities, SM, and %BF showed no association with race performance.

Anthropometry and training volume does not seem to have a major effect on race performance in a 24-h run. Instead, a fast personal best marathon time seems to be the only positive association with race performance in a 24-h run.

Objective:To investigate the effect of a multistage ultra-endurance triathlon on body composition in ultra-triathletes.Design:Descriptive field study.Setting:The “World Challenge Deca Iron Triathlon 2006” in Monterrey, Mexico, in which every day for 10 consecutive days athletes had to perform the distance of one Ironman triathlon.Subjects:Eight male ultra-endurance athletes (mean (SD) age 40.6 (10.7) years, weight 76.4 (8.4) kg, height 175 (4) cm and body mass index (BMI) 24.7 (2.2) kg/m2).Interventions:None.Main outcome measurements:Determination of body mass, protein mass, body fat, per cent body fat, mineral mass, total body water, intracellular water, extracellular water and lean body mass with a direct segmental multifrequency bioelectrical impedance method before the race and after each stage in order to show changes in body composition.Results:A statistically significant decrease of body mass (−2.4 kg, p = 0.014), body fat (−5 kg, p = 0.0078) and per cent body fat (−6.4%, p = 0.0078) occurred at the end of the first day compared to values taken in the pre-race period. In contrast, at the same time, a statistically significant increase of protein mass (+0.7 kg, p = 0.035), mineral mass (+0.2 kg, p = 0.04), total body water (+1.8 litres, p = 0.042), intracellular water (+1.6 litres, p = 0.034) and lean body mass (+2.6 kg, p = 0.023) was shown. After the first day until the end of the challenge, body fat (−3 kg, p>0.05) and per cent body fat (−3.9%, p>0.05) showed a statistically significant decrease, whereas the other parameters showed no changes.Conclusions:Athletes taking part in a multistage ultra-endurance triathlon over 10 Ironman triathlon distances in 10 consecutive days lost 3 kg of body fat; skeletal muscle mass, mineral mass and body water were unchanged.