This paper describes a panning videographic technique for measuring stride lengths and horizontal velocities of strides over an entire hurdle race. The technique requires that tapes of alternate black and white sections be placed at the inside border of the inside lane and the outside border of the outside lane of a track as spatial reference and that a vertical reference be videotaped when it is erected at different locations within the track. The stride lengths and horizontal velocities obtained with the panning technique were compared with the corresponding values that were obtained with conventional stationary camera techniques. The results indicate that if three panning cameras are used to cover the entire hurdle race, the average absolute errors in stride length and horizontal velocity are 0.07 m and 0.15 m/s, respectively. Such errors are considered acceptable for some applications. Certain properties of the panning technique are discussed.
John W. Chow is with the Department of Exercise Science, E101 Field House, University of Iowa, Iowa City, IA 52242.