Validation and Reliability of a Video-based, AI-Powered Motion Capture Application for Assessing Motor Performance: A Study Protocol

KIT –Die Forschungsuniversität in der Helmholtz-Gemeinschaft Institut für Sport und Sportwissenschaft (IfSS) Validation and Reliability of a Video-based, AI-Powered Motion Capture Application for Assessing Motor Performance: A Study Protocol Clara S. A. Zöller1, Bettina Barisch-Fritz1, Thorsten Stein1, Claudia Niessner1 Clara S. A. Zöller Funding: This work was developed in the research project ”COMO-Study“ (2023-2026). The national study on the impact of the COVID-19 pandemic on the physical and mental health and health behaviors of children and adolescents against the background of socioecological contexts in Germany is funded by the German Federal Ministry of Education and Research (funding reference number: 01UP2222). [email protected] Discussion Validation and Reliability Testing of a video-based, AIpowered motion capture app to assess MPS in children, adolescents and young adults 1) Do the app’s pose-estimation landmarks match those of the 3D system? 2) Does the app correctly evaluate the test results? Objective and Research Questions References Barnett, L. M., Stodden, D., Cohen, K. E., Smith, J. J., Lubans, D. R., Lenoir, M., Iivonen, S., Miller, A. D., Laukkanen, A., Dudley, D., Lander, N. J., Brown, H., & Morgan, P. J. (2016). Fundamental Movement Skills: An Important Focus. Journal of Teaching in Physical Education, 35(3), 219–225. https://doi.org/10.1123/jtpe.2014-0209 Ericsson, I., & Karlsson, M. K. (2014). Motor skills and school performance in children with daily physical education in school –a 9‐year intervention study. Scandinavian Journal of Medicine & Science in Sports, 24(2), 273–278. https://doi.org/10.1111/j.1600-0838.2012.01458.x Mauntel, T. C., Cameron, K. L., Pietrosimone, B., Marshall, S. W., Hackney, A. C., & Padua, D. A. (2021). Validation of a Commercially Available Markerless Motion-Capture System for Trunk and Lower Extremity Kinematics During a JumpLanding Assessment. Journal of Athletic Training, 56(2), 177–190. https://doi.org/10.4085/1062-6050-0023.20 Statista. (2024). Number of Smartphone Users From 2016 to 2021. Statista. https://www.statista.com/statistics/330695/number-of-smartphone-users-worldwide/ Woll, A., Klos, L., Worth, A., Hanssen-Doose, A., Hinz, T., Völkle, M., Burchartz, A., & Niessner, C. (2025). The German national cohort study on the development of motor performance, physical activity and health in children and adolescents: The MoMo 2.0-Study protocol. BMJ Open, 15(4), e094895. https://doi.org/10.1136/bmjopen-2024-094895 Young, F., Mason, R., Morris, R., Stuart, S., & Godfrey, A. (2023). Internet-of-Things-Enabled Markerless Running Gait Assessment from a Single Smartphone Camera. SENSORS, 23(2). https://doi.org/10.3390/s23020696 Zoeller, C. S., Niessner, C., Fleps, M., Klein, T., Hanssen-Doose, A., Burchartz, A., Woll, A., & Stein, T. (in Review). Videobased motion capture smartphone applications for testing human motor performance skills: A scoping review. JMIR Mhealth Uhealth. Icons: PowerPoint and Noun Project Methods 1Karlsruhe Institute of Technology, Institute of Sports and Sports Science 20-25 participants Children, adolescents and young adults Musculoskeletal injuries at present or within the previous six months Validation: Pearson correlation Reliability: Intraclass correlation coefficient New insights into the validity and reliability of a video-based, AI-powered app for assessing MPS Widespread smartphone availability enables broad access to MPS assessment through an app (Statista, 2024) Enables its application in large population-based studies Introduction Assessment of motor performance skills (MPS) to identify deficits and potential strengths (Barnett et al., 2016) Enables targeted interventions and helps leverage the benefits of well-developed motor performance skills (Barnett et al., 2016) Collected in physical education, motor development research and health-related studies (Ericsson & Karlsson, 2014, Woll et al., 2025) Test batteries →limited and subjective information Markerbased Motion Capture →expensive & timeconsuming (Mauntel et al., 2021) Alternative: markerless video-based, AI-powered motion capture (Young et al., 2023) Existing apps are available, but none for children and adolescents (Zoeller et al., in Review) Marker 3D Ca era Syste S artphone ca era