Abstract
Previous research concluded that Triple Iron ultra-triathletes were close to runners in anthropometry. We assessed similarities in anthropometry between 64 Triple Iron triathletes who competed over 11.4 km swimming, 540 km cycling, and 126 km running versus 95 100-km ultra-marathoners. Variables of anthropometry such as body mass, body height, length and circumferences of limbs, skin-folds and body fat, and training such as volume and speed were compared between ultra-triathletes and ultra-runners. The Triple Iron triathletes completed their race distance within 2811 min. (SD=379) and the 100-km ultra-marathoners within 691 min. (SD=117). Triathletes were younger, had higher body mass, shorter legs, higher circumference of upper arm and thigh, lower sum of skin-folds, and lower percent body fat compared to runners. Weekly training volume was higher for triathletes, and weekly hours in running and weekly kilometres in running were higher for runners. In the Triple Iron ultra-triathletes, the sum of eight skin-folds correlated to total race time. The circumference of upper arm, the sum of eight skin-folds, and percent body fat correlated with time in the running section .42, .47, and .43, respectively. In the 100-km ultra-marathoners, the sum of eight skin-folds, the skin-fold thickness of thigh, percent body fat, weekly running hours, and weekly running kilometres correlated with race time .55, .40, .56, -.50, and -.51, respectively. However, in the triathletes, none of these training variables was significantly correlated with race time. In the ultra-marathoners, the sum of eight skin-folds, the skin-fold thickness of thigh, percent body fat, weekly running kilometres, and speed in running during training were related to race time (correlations of .55, .40, -.28, and -.51, respectively). Overall, the ultra-triathletes were not similar to ultra-runners in their anthropometric measures and training variables.