Changing the IAAF Reaction Time Rule (Part 2)

Yesterday’s article on Armin Hary and other “False start incidents” prompted a more in depth look at the 0.100 second (or 100 milliseconds) reaction time rule.

The 0.100 number is based on an assumed minimum auditory reaction time, based on the average 0.132 seconds.

The IAAF commissioned the Neuromuscular Research Center (Department of the Biology of Physical Activity) at the University of Jyväskylä in Jyväskylä, Finland to examine neuromuscular reaction to the auditory signal used in the sprint start, and to determine whether the 100 ms limit is correct.

Once again, the IAAF New Studies in Athletics NSA is a rich resource for advanced track and field research.  The original research paper is called IAAF Sprint Start Research Project: Is the 100 ms limit still valid?  by Paavo V. Komi, Masake Ishikawa, Jukka Salmi.

Since the entire paper is copyrighted, I will only present the conclusions and recommendations which is of most interest to track and field readers.

This is in contrast to the proposed No False Start Rule.

IAAF Sprint Start Research Project: Is the 100 ms limit still valid?

The following conclusions can be drawn from the present study:

1. Great individual differences can be observed in reaction times.
2. Reaction time in the sprint start can be lower than the 100 ms IAAF criteria. The values can in some cases be even below 80 ms (see image)
   
3. Reaction time in the sprint start is parameter dependent and has different values in different body parts. The values are usually lower in the arms than the legs.
4. As the reaction to the auditory stimulus in the sprint start involves activation of several muscles in the whole body and consequently activation and movement in the various body parts (e.g. neck, head, shoulder, arms, back, abdomen, hip, knee and ankle), the current application of the IAAF rule does not take this important "whole body involvement" into consideration.
5. As the start of muscle activation is the first neuromuscular parameter to trigger the joint movement (and force production), the resulting kinematic changes should be considered as a key possibility for solving the complex problem of the current false start criteria.

Recommendations for the IAAF

1. As the present study gives essentially the same results as the ones published by independent researchers in Britain (PAIN & HIBBS, 2007) and Canada (BROWN et al., 2008), it is now recommended that the IAAF abandon the 100 ms minimum sprint reaction time level and its measurement with the current technical devices.
2. The level should be lowered to 80 or 85 ms, even if the block force production is still used as the parameter to set the level.
3. The IAAF should urgently examine possibilities for detecting the false start kinematically, so that the decision is based on the first visible movement regardless of the body part. This can be done with a system of high-speed cameras, which gives views of all the athletes on the start line. Modern technical possibilities are numerous in this regard, and the human eye can be considered as best to differentiate the first movement (shown by the high-speed camera) before the set minimum reaction time. Below is our suggestion for how the development project could be started. The figure does not show the cables to the monitor centre, in which one or two persons can make the decision a posteriori, but within 10-15 seconds after the gun firing.
   
4. Achieving point 3 above would lead to the situation where the rule could be changed so that no false starts are permitted