The sole is made from a molded sponge rubber. By the way only regulation broomball shoes or plain soled sports shoes are allowed. You can't use spikes or any other traction devices on your shoes, so forget about gluing sandpaper, or attaching snow chains to your old Nike's. Additionally there is added protection on the sides of the shoes and hard plastic toe caps. Goalies are not allowed to use a catching mit as hockey goalies can, but they are allowed a blocker.
Most goalies tend to use face protectors of some sort.
As with most organized sports, there are various levels of play in broomball. Your local recreational mixed league won't allow as much contact as a national tournament will. And you generally won't have people playing in it who are wanabe national stars. The leagues are targeted to the participants so as to assure everyone gets to play comfortably. But at the national level you will find people who play like they are possesed.