They'll only hit you once, and not again when you've stopped moving. So as long as you don't land on top of a tiger snake, you'll be good. :) Source: Have hit

They'll only hit you once, and not again when you've stopped moving. So as long as you don't land on top of a tiger snake, you'll be good. :) Source: Have hit plenty of trees MTB riding, and seen snakes, but fortunately not both at the same time.