SkiTechCoach: A Multimodal Alpine Skiing Dataset with 3D Body Pose, Sole Pressure, and Expert Coaching

Institute of Science Tokyo
ACM MMSports 2025

Overview of the proposed SkiTechCoach dataset. Each ski sequence is captured on an indoor simulator and includes synchronized 3D poses, sole pressure measurements, FIS points as objective skill indicators, and expert coaching feedback in both verbal and visual (freehand annotation) forms.

Abstract

We present SkiTechCoach, a novel alpine skiing dataset designed to advance data-driven skill assessment and coaching. Our dataset includes sole pressure and 3D pose measurements from an indoor ski simulator, along with two objective performance indicators: FIS points and coaching commentary. The dataset comprises 160K video frames of 71 high-quality sequences of 20 expert skiers performing slalom turns at varying speeds, synchronized with sole pressure, pose trajectories, FIS points, and coaching feedback delivered via verbal and visual annotations. To demonstrate its utility, we establish baselines for FIS point estimation using both pressure and pose modalities, and we explore automated coaching generation through multimodal large language models. Our empirical analysis reveals that existing LLM-based coaches lack the domain expertise required for nuanced alpine-ski feedback, underscoring the need for specialized model fine-tuning. We release SkiTechCoach to catalyze future research on ski skill acquisition and intelligent coaching systems that leverage synchronized wearable pressure sensing and markerless motion capture.

Examples of Data Included in SkiTechCoach

Statistics of the proposed SkiTechCoach dataset. A total of 71 skiing runs were recorded. We additionally collected 305 coaching clips (213 with visual annotations), amounting to 136 min.

BibTeX

@inproceedings{hirano2025skitechcoach,
  author = {Hirano, Toshihiro and Tabei, Yuki and Peng, Yichen and Liao, Chen-Chieh and Wu, Erwin and Koike, Hideki},
  title = {SkiTechCoach: A Multimodal Alpine Skiing Dataset with 3D Body Pose, Sole Pressure, and Expert Coaching},
  year = {2025},
  isbn = {9798400711985},
  publisher = {Association for Computing Machinery},
  address = {New York, NY, USA},
  url = {https://doi.org/10.1145/3728423.3759413},
  doi = {10.1145/3728423.3759413},
  booktitle = {Proceedings of the 8th International ACM Workshop on Multimedia Content Analysis in Sports},
  pages = {39–46},
  numpages = {8},
  keywords = {3d body pose, coaching, dataset, skiing, sole pressure, winter sports},
  location = {Dublin, Ireland},
  series = {MMSports '25}
}