They're treading water the entire time, which makes all the sneaky elbowing somehow even more impressive.
Fun fact: "Players tread water the entire match and can swim up to five kilometres per game."
You pay five grand for suspension and disc brakes specifically so you can ride down things that'll wreck them.
Fun fact: The sport started in 1970s Marin County with riders racing modified beach cruisers down Mount Tamalpais.