The Z Strategy uses a value known as Z indice that searchs the person, transforming his physical fitness results in absolute terms, in unity of standard desviation using the follow formula:
Z Formula Being:
IR - Person Individual Test Result
GA - Group Average
SD - Standard Desviation
The analysis of Z indices make possible to compares persons of different ages, sex, and physical fitness level, using the same group reference for sex and age. So, a boy 13 years-old(chronological age) will be compared with the reference standard group, that means, 13 years-old male group. When this boy get 14 years old will be used, then, the 14 years-old male standard reference and son on.
Doing that, we'll can attend his growth, got by the absolute values, for example, jumping 40 centimeters(15,80 inch) in thirteen's and pass to 44 centimeters(17,40 inch) with 14 years-old, we can do the same through the Z indice values, for example: got a Z of 1,0 in thirteen's and 1,5 in fourteen's; becoming this way one of most simple, practice and precise technics to differ growth from development, or, growth effects from physical training effects.
Getting a Z of 1 (Z=1) means the person moves away, exactly one standard desviation up to population average. We can say he presents a result 84,13% higher than the one presented by the population or that just 15,87% of that population with same sex and age can get upper results.
A Z of 0 (Z=0) means the person got a result equal of standard reference. So, the more Z indice value moves away as a positive value (right side), the more would be the condition of the person, except tests that measure time like velocity and agility, where negative values (left side) show better performance.
The experiency with different groups( since sedentaries until olimpic athlete) enabled to create a practice results classification being:
> 2Excellent
1 til 1,99 Very Good
0 til 0,99Good
-0,99 til -0,01Regular
-1 til -1,99Poor
< 2Very Poor
After we've got the Z indices, we'll be able to represent the values in a graphic called Z-Fitnessgram, where is possible to see all physical fitness.
Through this graphic, it'll be possible to detect talents by comparing the person graphic with the graphic of an athlete(or an average of a sport). To understand it better look for more examples or ask us clicking on Feedback.

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