# Reply To: U.S. Question, is interval for 50yd repeat length for 500 free too long?

Home Forums General USRPT Topics U.S. Question, is interval for 50yd repeat length for 500 free too long? Reply To: U.S. Question, is interval for 50yd repeat length for 500 free too long?

#2379
oldschoolc
Participant

Well if you are good with a hand held calculator it will take about six steps. I use to do it by calculator and man what a pain! Then I found out how to do it in EXCEL and now it takes about 10 seconds.

Go into EXCEL help or there has to be a youtube video on it and it will show you how. it’s really simple. I’m no computer wiz and I figured it out.

Remember it’s the “average distance to the mean”. I use it to show reliability of the mean. Or how good is that time. Higher stdev. the lower relability and the lower the stdev.the higher relability.
It comes in handy when doing race projections as using just averages can be very misleading.

Swimmer A has avg time of 32.23 on 50s on ??? and a stdev of 1.22, so they now have a race range of 32.23 to 33.45, big difference if you just used the avg to figure projected race time.

Swimmer B has avg time of 32.23 on 50s but a stdev of .34, they have a race range of 32.23 to 32.57. same avg but much better reliability.

May be one explaination of how two swimmers with the same average can go different times.

Hope this helps ðŸ™‚

Oldschool

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