## 5 Conclusions  
A new protocol has been developed to measure 3D pedal kinematics based on a non-optimal procedure. The number of physical markers used has been reduced to avoid loss of markers due to masking or artefacts due to soft mass movements.  
Protocol evaluation through its application to gait analysis has found that it correlates very well with other widely accepted protocols in the literature, especially in the sagittal plane. Those joint angles that have shown a lower correlation are defined outside the sagittal plane and are more difficult to quantify accurately with this technology, regardless of the marker protocol used. In any case, the conclusions obtained in the gait analysis can be extrapolated to cycling since the markers of the new protocol are in positions where there is no presence of large soft masses. Therefore, in response to the first research question, the proposed protocol provides kinematic results in pedalling analysis that are equivalent in accuracy and repeatability to protocols commonly used in gait analysis.  
In answer to the second question posed in the motivation of this paper, joint angles outside the sagittal plane may account for 30-40% of the maximum values reached in the sagittal plane, especially in the ankle. The results obtained have shown that angular velocities occurring outside the sagittal plane are not negligible, reaching values up to 35-45% of the velocities contained in the sagittal plane. Therefore, when estimating joint powers, it is advisable to consider the components in the frontal and transverse planes. Similarly, linear accelerations outside the sagittal plane are smaller than those contained in the sagittal plane reaching maximum values in the order of 20-30% of the maximum value contained in the sagittal plane. The preliminary results obtained by the authors of this paper suggest that inertial effects outside the sagittal plane should not be neglected and can be very important, especially at positions such as the TDC and BDC. These conclusions will be developed in a future paper.  
The following supporting information can be downloaded at: [[https://www.mdpi.com/article/10.3390/app15126382/s1](https://www.mdpi.com/article/10.3390/app15126382/s1)]([https://www.mdpi.com/article/10.3390/app15126382/s1](https://www.mdpi.com/article/10.3390/app15126382/s1)), Table S1: Markers Information; Document SI: Kinematic Temporal Evolution.  
**Author Contributions**: Conceptualisation, J.O.; methodology, E.M.-S. and J.O.; software, E.M.-S.; validation, E.M.-S., E.S.-V., J.M. and J.O.; formal analysis, E.M.-S. and J.O.; investigation, E.M.-S., E.S.-V., J.M. and J.O.; resources, E.M.-S., E.S.-V. and J.O.; writing--original draft preparation, E.M.-S. and E.S.-V.; writing--review and editing, J.M. and J.O.; supervision, J.M. and J.O.; project administration, J.O.; funding acquisition, J.M. and J.O. All authors have read and agreed to the published version of the manuscript.  
This research was funded by the Ministry of Economy, Industry and Competitiveness of the Spain Government with the project DPI2016-80796-P and by the Regional Government Department of Economic Transformation, Industry, Knowledge and Universities of Andalusia with the project ProyExcel_00747.  
The study was conducted in accordance with the Declaration of Helsinki, and approved by the Andalusian Biomedical Research Ethics Platform (code number 0230-N-22).  
Informed Consent Statement: Informed consent was obtained from all subjects involved in this study.  
The data presented in this study are available on request from the corresponding author. Data are not publicly available due to ethical reasons.  
The authors thank the Ministry of Economy, Industry and Competitiveness of the Spain Government and the Regional Government Department of Economic Transformation, Industry, Knowledge and Universities of Andalusia.  
The authors declare no conflicts of interest.