Why do sports shoes stink of cat piss?

[Piemaster]

My vibram fivefingers smell really bad. Worn sockless, so nothing to help absorb any sweat, and have been getting damp with the weather recently. The smell didn't improve with a run through the washing machine, if anything they smelt worse until they had dried out afterwards. A set of large ziplock bags from Poundland has helped the situation somewhat.
Actually the smell is something like the wetsuit boots when sailing.

The cycling boots, winter boots at, that I'm using as nothing else with me at moment hardly smell at all.

Must be some materials are better at absorbing and releasing sweat/bacteria than others.

 

[Norm]

I'm not sure about this. Water has to be stored in dark containers to stop the formation of algae. When travelling, water cans should not be clear or uncoloured polythene as the water soon goes off/green.

I'd have thought that involving warm water would so obviously produce a different result from hanging your shoes in the breeze on a sunny afternoon that it wasn't even worthy of a mention. Sticking it at the focal point of a 6m magnifying glass won't do them much good either, even though that's the also just using sunlight.