Gymnasts are also usually quite small, there is actually some debate over whether gymnastics can affect growth (but I don't think there is much evidence behind this). 
According to this website American gold medalist Gabrielle Douglas is 

> four feet, eleven inches, and 90 pounds

.
http://www.boston.com/sports/blogs/statsdriven/2012/08/the_bodies_of_champion_gymnast.html

Also height isn't always an advantage in soccer, just look at the average height of the Barcelona team (Messi, Xavi, Iniesta, Pedro etc).