Guys,
I see a lot of confusion, a lot. Players are with the national team for approximately 3 weeks before the start of the work cup, it is a long time full of opportunities if you want to destroy someone, not a lot of time if you want to improve. Do you really think that fastest players were fastest because of the 3 weeks spent with the national team?
Players are selected and not trained, in a general sense (of course when they are playing with the national team, less so with their clubs).
Soccer is a complex sport like many others, in which the result is determined by a multitude of factors and not easily identifiable. You look a the data, fitness, average velocity, ball possession and so on, at the end maybe the only goal was scored in a corner.
In track and field, let’s say 100 m dash, it is easier to look at quantitative data and have insights (reaction time, start and drive, max V etc.).
For example, ball possession is not a good indicator of winning probabilty, especially in the last decade, maybe two. If any of you have seen the statistics of the semi-final of Champions’ League, Barcellona-Inter, ball possession was around 70% for Barcellona, but you remember who won, don’t you?
There was a paper published a few years ago, where it was shown that lesser teams against better teams ran substantially more. You can thus conclude that lesser teams were more fitted, can’t you?
Wrong conclusion. They were chasing all the time.