Measurement of running speed, stride length, and step frequency of 400 m track and field running using a high-precision kinematic global navigation satellite system

Abstract

Running speed, stride length, and step frequency of a 400 m track and field run were measured using a high-precision kinematic global navigation satellite system (GNSS, 100 Hz). One subject (men, 22 years old, 400 m runner) was participated. GNSS antenna was attached to the top of the head using head gear and the subject was tried to run maximally for 400 m. The stride length and cycle time were determined from the change in the height of the head position. Lowest head position was seen at the timing of the foot landing during running. The distance and time were analyzed between every of foot landing during 400 m. Video was recorded from the back ward position of the runner Video recording and two-dimensional analysis were conducted in the last part of 10 m section to evaluate the validity of the time, stride length and step frequency measured by GNSS. The time, stride length, and step frequency between steps at last 10 m part measured by both GNSS and video were perfectly consistent (Speed: 2.54 vs 2.52 sec; Average per step: 0.32 vs 0.32 sec; step frequency: 3.15 vs 3.18 Hz). The analysis of running speed was measured with high accuracy. The stride length and step frequency were perfectly matched between the GNSS and video data based on the head change pattern.