Impact of Cycling Intensity on Cycle-run Transition in Female Triathletes

Abstract

PURPOSE: The purpose of the study was to determine the impact of intensity during the final km of a cycling bout on subsequent run and overall cycle-run (CR) performance. A secondary aim of the study was to examine how manipulations in cycling power affect cycle-run performance in female triathletes exclusively. METHODS: Nine well-trained female triathletes participated in the study. The triathletes completed two CR sessions (20 km cycle, 5 km run). The intensity of the first 19 km of cycling was equivalent to peak power at 70% of peak oxygen consumption (O 2 peak) and the final 1 km varied between power achieved at 95% of O 2 peak (high intensity, HI) and power achieved at 50% of O 2 peak (low intensity, LI). The 5 km run was completed as fast as possible. RESULTS: Mean blood lactate concentration [La - ] was significantly higher during the run following the cycling bout ending with a HI rather than a LI (11.5 ± 0.64 mmol/L vs. 9.3 ± 0.72 mmol/L). Run performance was not significantly different between HI and LI (24:54 ± 02:53 min vs. 00:24:36 ± 00:03:17 min). As well, no significant differences were found between overall CR sessions (01:23:23 h ± 00:05:47 min vs. 01:23:50 h ± 00:07:01 min). CONCLUSION: Despite increases in [La - ], cycling intensity during the final stages of a 20 km cycling bout does not impact run or CR performance in well-trained female triathletes.