Kenny Mac, times do sound about right for hand timng.
However, I would suggest another way to do hand times trials for 30m and 60m or 100m that has worked well for any athlete I have timed in regard to actual electronic times when they race. This involves the timer, who is also the starter, standing at the finish of the 30m, 60m, or 100m. When he yells out go he or she presses the clock simultaneously and obviously stops the watch on the line. However, what ever time that is clocked has to be adjusted to allow for the speed of sound as the sprinter has to wait for the sound to travel before he hears it and reacts to it. From a rough calculation from the speed of sound, we have estimated that sounds travels at around 0.12 for 30m. Thus, any time clocked by my method takes off 0.12 for 30m, 0.24 for 60m, nd 0.40 for 100m.
Though the method is not exact, is it much more accurate than ordinary hand timing.
Again, I repeat that the timer who is also the starter, must press the clock at the exact moment he yells go. For athletes who do not have the luxary of affording expensive electronic equipment, I promise that such a method will give you a much more accurate and honest summary of one’s own ability and potential. I have seen to many hand timed estimates that falsely predict fast times only to have the truth demoralise the athlete when he actually competes.
Neverthless, 30m potential is absolutely crucial to 60m and 100m times.
While different splits may not be exact for predicting 100m times given differing abilities, I have prepared the following chart based on the splits of many leading athletes.
Figures worked out form 60m divided by 30m, and 100m divided by 60m. This is done on the basis that in order to maximise potential, one must be able to run an efficient 60m before one can run properly at 100m.
Figures worked out by 60m divided by 30m, and 100m divided by 60m. This is done on the basis that in order to maximise potential, one must be able to run an efficient 60m before one can run properly at 100m.
For example based on Johnson’s 1987 times, 60-30m = 1.678 100m-60m = 1.540
Flo Jo 1988 OG semi final
Calvin Smith 1988
Flo Jo 1988 final
Kenderis Bremen 2002
Hence, given that all of these athletes are world level medalists, I have averaged their proportions to come up with following chart base on an average of a conversion figure of 1.673 for the 60-30m, and for the 100-60m a conversion figure of 1.535. While I remain confident with 60-100m predictions, I am not so sure that 30m times are a good basis for predicting times. Logically, comparing 60m times with 100m is so much wiser given that the longer distance reduces the chance of uncertain variables. This may include the fact that 30m trials do tend to cause athletes to waste much more energy than when trying to run efficient and technically sound at a longer distance. For this reason, I always emphasise 60m trials as my main test over a shorter distance to measure reaction, acceleration, and the transition to top speed.
As indicated by snelkracht, and from the above figures, it is obviously smarter to compare your 60m times with 100m than 30m with 60m or 100m. However, the above predicted times can only result from athletes that are highly efficient technically at top speed between 30m and 100m.