The reliability and validity of the PowerTap P1 power pedals before and after 100 hours of use

Purpose: The aims of this study were to 1) evaluate agreement between the PowerTap P1 (P1) pedals and the Lode Excalibur Sport cycle ergometer, 2) investigate the reliability of the P1 pedals between repeated testing sessions, and 3) compare the reliability and validity of the P1 pedals before (P10) and after (P1100) ~100 h of use. Methods: Ten participants completed four 5-min sub-maximal cycling bouts (100, 150, 200 and 250 W), a 2-min time-trial and two 10-s all-out sprints on two occasions. The above protocol was repeated after fifteen months and ~100 h of use. Results: Significant differences were seen between the P10 pedals and the Lode Excalibur Sport at 100 W (P = 0.006), 150 W (P = 0.006), 200 W (P = 0.001) and 250 W (P = 0.006) and during the all-out sprints (P = 0.020). Following ~100 h of use, the P1100 pedals did not significantly differ from the Lode Excalibur Sport at 100 W (P = 0.799), 150 W (P = 0.183), 200 W (P = 0.289) and 250 W (P = 0.183), during the 2-min time-trial (P = 0.583) or during the all-out sprints (P = 0.412). The coefficient of variation for the P10 and P1100 ranged from 0.6–1.3% and 0.5–2.0%, respectively, during the sub-maximal cycling bouts. Conclusion: The P1 pedals provide valid data after ~100 h of laboratory use. Furthermore, the pedals provide reliable data during sub-maximal cycling, even after prolonged use.