Sports and elevation

I know that Ecuador's Football national team is considered a team that's very hard to beat when playing a home match in the country's capital,

In all sprint events up to 400 meters elevation is an advantage. the same is for all the jumping events. At long distances events, elevation is a dis advantage. At the olympics in  Mexico City 1968 (2200 meters above sea level) world record were broken: 100 m, 200 m, 400 m, long jump, triple jump , 4X100, 4X400. On the other hand, times at distances from 5000 m and up were much slower then at sea level.