Reliability of power settings of the Wahoo KICKR power trainer after 60 hours of use

Purpose: The purpose of this study was to assess the reliability of power output measurements of a Wahoo KICKR Power Trainer (KICKR) on two separate occasions, separated by fourteen months of regular use (~1 h per week).

Methods: Using the KICKR to set power outputs, powers of 100-600W in increments of 50W were assessed at cadences of 80, 90 and 100rev.min-1 which were controlled and validated by a dynamic calibration rig (CALRIG).

Results: A small ratio bias of 1.002 (95%rLoA: 0.992-1.011) was observed over 100-600W at 80-100rev.min-1 between Trial 1 and Trial 2. Similar ratio biases with acceptable limits of agreement were observed at 80rev.min-1 (1.003 (95% 0.987-1.018)), 90rev.min-1 (1.000 (95%rLoA: 0.996-1.005)) and 100rev.min-1 (1.002 (95%rLoA: 0.997-1.007)). Intraclass correlation coefficients (ICC) with 95% confidence intervals (CI) for mean power (W) between trials was 1.00 (95%CI: 1.00-1.00) with a typical error (TE) of 3.1W and 1.6% observed between Trial 1 and Trial 2.

Conclusion: When assessed at two separate time points fourteen months apart, the KICKR has acceptable reliability for combined power outputs of 100-600W at 80-100rev.min-1, reporting overall small ratio biases with acceptable limits of agreement and low TE. Coaches and sports scientists should feel confident in the measured power output by the KICKR over an extended period of time when performing laboratory training and performance assessments.