13/08/2019   Brian Hanley, Catherine B. Tucker e Athanassios Bissas: results of the study and survey of 2018






Last year Brian Hanley together with Catherine B. Tucker and Athanassios Bissas (Carnegie School of Sport, Leeds Beckett University, Leeds, UK) had proposed to the judging body a survey through a series of online videos.

The results of this study titled "Assessment of IAAF Racewalk Judges' Ability to Detect Legal and Non-legal Technique"  were recently published by the authors on "Frontiers in sport and Active Living".

 

The original article in English can be consulted in our section "Techniques, rules and conventions" -> sub-section "Publications and Reports on race walking“.

 

We do not hide his interest in particular in this historical moment in which we are seeing an indiscriminate increase in the sanctioning of bent knee and not only at local level.

The three figures (4, 5 and 6) on pages 7 and 8 and the explanation on page 6 are, in our opinion, of great interest to everyone.

 

We thanks the authors.

 

 

Summary

 

The aims of this study were:

- first: to analyze racewalking judges' accuracy in assessing technique and, 

- second: to measure flight times across a range of speeds to establish when athletes were likely to lose visible contact. 

 

Twenty racewalkers were recorded in a laboratory using a panning video camera (50 Hz), a high-speed camera (100 Hz), and three force plates (1,000 Hz). 

 

Eighty-three judges of different IAAF Levels (and none) viewed the panned videos online and indicated whether each athlete was racewalking legally. 

 

Flight times shorter than 0.033s were detected by fewer than 12.5% of judges, and thus indicated non-visible loss of contact. Flight times between 0.040 and 0.045s were usually detected by no more than three out of eight judges. Very long flight times (≥0.060s) were detected by nearly all judges. 

 

The results also showed that what judges generally considered straightened knees (>177°) was close to a geometrically straight line. 

 

Within this inexact definition, IAAF World Championship-standard Level III judges were most accurate, being more likely to detect anatomically bent knees and less likely to indicate bent knees when they did not occur. 

 

For the second part, the men racewalked down a 45-m indoor track at 11, 12, 13, 14, and 15 km/h in a randomized order, whereas the women's trials were at 10, 11, 12, 13, and 14 km/h. 

 

Flight times, measured using an OptoJump Next photocell system (1,000 Hz), increased for the men from 0.015s at 11 km/h to 0.040s at 14 km/h and 0.044s at 15 km/h, and for the women from 0.013s at 10 km/h to 0.041s at 13 km/h and 0.050s at 14 km/h. 

 

For judging by the human eye, the threshold for avoiding visible loss of contact therefore occurred for most athletes at ~14 km/h for men and 13 km/h for women.

 

 

 

Download of full report: click here

 

 

 

 



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