Kranzinger Stefan, Kranzinger Christina, Kremser Wolfgang, Duemler Burkhard
Human Motion Analytics, Salzburg Research Forschungsgesellschaft mbH, Salzburg, Austria.
Athlete Performance, Adidas AG, Herzogenaurach, Germany.
Front Sports Act Living. 2025 Jun 30;7:1627820. doi: 10.3389/fspor.2025.1627820. eCollection 2025.
This study investigates performance development and the relationship between subjective and objective training assessments in female youth soccer using wearable sensor technology. The aim of this study was to assess how subjective post-training ratings (intensity and happiness) relate to high-percentile performance outputs, and to identify longitudinal trends in female youth soccer players using IMU-based wearable data. Data were collected over a 14-month period from 46 players (U17 and U20 teams) equipped with foot-mounted inertial measurement units (IMUs) during regular training sessions. Objective performance metrics, including 95th percentile of ball speed, peak speed, and absolute distance, were derived using a multi-stage machine learning pipeline, while subjective metrics (intensity and happiness) were collected via post-session Likert-scale questionnaires using an app. Using the modified Mann-Kendall test, we found 30 significant longitudinal trends, with 14 positive and 16 negative trends across key performance metrics. Peak speed showed the highest number of trends (13), followed by absolute distance (10) and ball speed (7). Correlation analyses based on the Spearman coefficient (with False Discovery Rate correction) revealed meaningful associations between subjective self-assessments and high-percentile performance metrics, with notable differences across player positions and age groups. A robustness check confirmed these patterns also hold when analyzing the 99th percentile of performance outputs. Our findings underscore the value of combining wearable sensor data with subjective evaluations for individualized, role-specific performance monitoring and training optimization in youth soccer. However, as an exploratory study with a single cohort, findings require further validation in broader populations.
本研究利用可穿戴传感器技术，调查了女子青年足球运动员的表现发展以及主观和客观训练评估之间的关系。本研究的目的是评估主观的训练后评分（强度和愉悦感）与高百分位表现输出之间的关系，并利用基于惯性测量单元（IMU）的可穿戴数据确定女子青年足球运动员的纵向趋势。在14个月的时间里，从46名球员（U17和U20球队）中收集数据，这些球员在常规训练期间佩戴了安装在足部的惯性测量单元（IMU）。客观表现指标，包括球速的第95百分位、峰值速度和绝对距离，是通过一个多阶段机器学习管道得出的，而主观指标（强度和愉悦感）则通过应用程序在训练后通过李克特量表问卷收集。使用修正的曼-肯德尔检验，我们发现了30个显著的纵向趋势，在关键表现指标中有14个正向趋势和16个负向趋势。峰值速度显示的趋势数量最多（13个），其次是绝对距离（10个）和球速（7个）。基于斯皮尔曼系数的相关性分析（采用错误发现率校正）揭示了主观自我评估与高百分位表现指标之间的有意义关联，不同球员位置和年龄组之间存在显著差异。一项稳健性检验证实，在分析表现输出的第99百分位时，这些模式同样成立。我们的研究结果强调了将可穿戴传感器数据与主观评估相结合，用于青年足球个性化、特定角色的表现监测和训练优化的价值。然而，作为一项针对单一队列的探索性研究，研究结果需要在更广泛的人群中进一步验证。
