Caveats and Recommendations to Assess the Validity and Reliability of Cycling Power Meters: A Systematic Scoping Review

Abstract

A large number of power meters have become commercially available during the last decades to provide power output (PO) measurement. Some of these power meters were evaluated for validity in the literature. This study aimed to perform a review of the available literature on the validity of cycling power meters. PubMed, SPORTDiscus, and Google Scholar have been explored with PRISMA methodology. A total of 74 studies have been extracted for the reviewing process. Validity is a general quality of the measurement determined by the assessment of different metrological properties: Accuracy, sensitivity, repeatability, reproducibility, and robustness. Accuracy was most often studied from the metrological property (74 studies). Reproducibility was the second most studied (40 studies) property. Finally, repeatability, sensitivity, and robustness were considerably less studied with only 7, 5, and 5 studies, respectively. The SRM power meter is the most used as a gold standard in the studies. Moreover, the number of participants was very different among them, from 0 (when using a calibration rig) to 56 participants. The PO tested was up to 1700 W, whereas the pedalling cadence ranged between 40 and 180 rpm, including submaximal and maximal exercises. Other exercise conditions were tested, such as torque, position, temperature, and vibrations. This review provides some caveats and recommendations when testing the validity of a cycling power meter, including all of the metrological properties (accuracy, sensitivity, repeatability, reproducibility, and robustness) and some exercise conditions (PO range, sprint, pedalling cadence, torque, position, participant, temperature, vibration, and field test).

Competitive Racing in Virtual Cycling—Is It Possible, Realistic, and Fair?

“…Pertaining to the validity of the equipment's power outputs, there does appear to be a reasonably high degree of agreement in the present study. Measuring power in cycling is recognized as complex (Bouillod et al, 2022), and differences in measures can always be expected due to random measurement errors. Previously, however, when power meters were used primarily to guide training and sometimes evaluate racing, the demands were different; beyond some basic accuracy (values attained are near the true value), repeatability and reproducibility were most crucial from a user perspective (that the measure is consistent over time, for similar conditions and over variations in conditions).…”

Using Wearable Sensors to Estimate Mechanical Power Output in Cyclical Sports Other than Cycling—A Review

“…This method revolves around using the main propulsion force or torque in the specific sport, such as the force of the hands on the oar, paddle, or wheel. The main propulsion method is widely used in cycling power meters, where the force of the feet on the paddles is considered as the main propulsion force [ 5 , 6 , 7 ]. By multiplying the main propulsion force or torque with the corresponding linear or angular velocity vector, one obtains the mechanical power responsible for most of the propulsion.…”

“…Therefore, in-field mechanical power estimation might be favorable for coaches and athletes as opposed to laboratory-based mechanical power estimation. Accordingly, in-field estimation of mechanical power in cycling is well-integrated in various cycling power meters, which are widely used by coaches, sport scientists, and athletes [ 5 , 6 , 7 ]. In cycling, power meters are often used to gain insight in power profiling, training load, and performance assessments and for establishing training zones [ 7 ].…”

“…As several reviews discuss the application of power meters in cycling [ 5 , 6 , 7 ], cycling will be omitted from this review.…”

Reproducibility of 20-min Time-trial Performance on a Virtual Cycling Platform

“…Second, although the reproducibility of mean power output was high, we could not examine the accuracy and the validity of power outputs generated by the participants' trainer, rather than how consistently they were reproduced by the individual riders. Given the potential differences in types of trainers used, discrepancies across models/devices might be expected [25,26]. However, as suggested by Atkinson and Nevill [27], the reproducibility of any new measurement tool should be tested before its validity, as it is unlikely that it will be valid if not adequately consistent.…”