Abstract des Autors

The aim of the present study was to examine the relationship between the performance heart rate during an ultra-endurance triathlon and the heart rate corresponding to several demarcation points measured during laboratory-based progressive cycle ergometry and treadmill running. Less than one month before an ultra-endurance triathlon, 21 well-trained ultra-endurance triathletes (mean ± s: age 35 ± 6 years, height 1.77 ± 0.05 m, mass 74.0 ± 6.9 kg,
  =  4.75 ± 0.42 l · min−1) performed progressive exercise tests of cycle ergometry and treadmill running for the determination of peak oxygen uptake (
), heart rate corresponding to the first and second ventilatory thresholds, as well as the heart rate deflection point. Portable telemetry units recorded heart rate at 60 s increments throughout the ultra-endurance triathlon. Heart rate during the cycle and run phases of the ultra-endurance triathlon (148 ± 9 and 143 ± 13 beats · min−1 respectively) were significantly (P < 0.05) less than the second ventilatory thresholds (160 ± 13 and 165 ± 14 beats · min−1 respectively) and heart rate deflection points (170 ± 13 and 179 ± 9 beats · min−1 respectively). However, mean heart rate during the cycle and run phases of the ultra-endurance triathlon were significantly related to (r  =  0.76 and 0.66; P < 0.01), and not significantly different from, the first ventilatory thresholds (146 ± 12 and 148 ± 15 beats · min−1 respectively). Furthermore, the difference between heart rate during the cycle phase of the ultra-endurance triathlon and heart rate at the first ventilatory threshold was related to marathon run time (r  =  0.61; P < 0.01) and overall ultra-endurance triathlon time (r  =  0.45; P < 0.05). The results suggest that triathletes perform the cycle and run phases of the ultra-endurance triathlon at an exercise intensity near their first ventilatory threshold. Verf.-Referat