|Coopers 12-min run|
Coopers 12-min run test is a maximal test performed on a flat measured running surface.
The 12 min run test is also called the Cooper test. It was developed in the sixties as an easy tool to estimate VO2max in soldiers.
The validity of this test is quite good if you are accustomed to running. For people not used to running it can be difficult to administer the speed from start to end and also peripheral discomfort in the legs can limit performance rather than circualatory capacity.
Besides the original validation of the 12-min test on soldiers, there has been other validations on other populations. In at least one of them (couldn't find the ref right now), the analysis showed that a specific performance indicated a 5 % higher VO2max for woman. This could be explained differences in running economy between sexes and this has actually been shown in some studies.
I beleive the yo-yo test is more relevant to soccer fitness as compared to the cooper test.I believe it is more accurate for the energy systems used in the game