Inertial Sensor-Based Estimation of Temporal Events in Skating Sub-Techniques While In-Field Roller Skiing

Area of Science:

• Sports Science
• Biomechanics
• Human Movement Analysis

Background:

• Cross-country roller ski skating performance relies on efficient technique and precise timing.
• Accurate measurement of inner-cycle parameters and sub-techniques is crucial for training optimization.
• Existing methods for field assessment of these parameters are limited.

Purpose of the Study:

• To adapt and validate a treadmill-based method using inertial measurement units (IMUs) for field assessment of cross-country roller ski skating.
• To determine the reliability and accuracy of IMUs in detecting temporal events, inner-cycle parameters, and sub-techniques during roller ski skating.
• To evaluate the performance of the IMU method across different skiing intensities and ski types.

Main Methods:

• Eleven athletes performed 4 laps of 2.5 km roller skiing at low and high intensities using two ski types.
• Inertial measurement units (IMUs) were attached to athletes' wrists and skis.
• Reference systems included pressure insoles and force-measuring poles to validate IMU data.

Main Results:

• The IMU-based method successfully detected over 97% of temporal events identified by the reference system.
• Inner-cycle temporal parameters were measured with a precision between 49 and 59 milliseconds (3.9%–13.7% of cycle duration).
• High reliability was demonstrated for using IMUs to determine temporal events, inner-cycle parameters, and sub-techniques in field conditions.

Conclusions:

• Wearable inertial measurement units (IMUs) provide a reliable method for assessing cross-country roller ski skating technique in field settings.
• The validated IMU method enables accurate determination of temporal events, inner-cycle parameters, and sub-techniques.
• This technology can be a valuable tool for coaches and athletes to analyze and improve roller ski skating performance.