The reliability of a laboratory-based 4 km cycle time trial on a Wahoo KICKR power trainer

The purpose of the present study was to evaluate the reliability of a laboratory-based 4 km cycling time trial using a Wahoo KICKR Power Trainer. Twelve trained male cyclists (age: 34.0 ± 6.5 years; height: 1.78 ± 0.62 m; training per week: 11.9 ± 2.6 hours) completed three 4 km time trials on the Wahoo KICKR Power Trainer, with each time trial separated by a minimum of two days. During all time trials, mean power (W), cadence (rpm), speed (km.h-1), heart rate (bpm) and total time (s) were recorded with rating of perceived exertion (6-20) collected immediately post time trial. Average Intraclass Correlation Coefficients (ICC) between time trials (2v1, 3v2, 3v1) for power was 0.94 (95%CI: 0.85-0.98), cadence 0.73 (95%CI: 0.46-0.90), speed 0.54 (95%CI: 0.22-0.82), heart rate 0.93 (95%CI: 0.84-0.98) and total time 0.64 (95%CI: 0.34-0.86). Mean reliability expressed as the coefficient of variation (CV) and typical error of measurement over the three time trials was 3.4%, 5.2%, 4.2%, 1.6% and 4.3% for power, cadence, speed, heart rate and total time, respectively. Average power measured during a laboratory-based 4 km cycling time trial is highly reliable in trained cyclists making it a reliable method for monitoring cycling performance., however, caution should be applied when assessing cadence, speed and total time due to the larger typical errors when completed on the Wahoo KICKR Power Trainer.