Even lurking just a bit on fitness communities shows that people often talk about single digit body fat levels.
Why is this wanted?
Provided that one is not overweight, what benefits (except for looking better) can one obtain from losing fat alone (as opposed to building strength / stamina / etc?)
Assuming that all other parameters remain unchanged, what feats could one achieve with lower body fat levels? What exercises could one do that would otherwise be impossible, in what disciplines could one outperform a competitor that is similarily built and trained but with slightly higher fat levels, etc?
I know that athletes often drop fat to lowest possible levels just days before a competition and, once the competition is finished, return to slightly higher levels. Why are they doing this? Are they doing this because this allows them to achieve feats they would otherwise be impossible for them? Or, on the contrary, are they doing this because they wish to fit into a lower weight class and thus face a weaker competition at the cost of hampering their own abilities?