Rachael Riddington is a respectable Jamberoo pastor but will unleash her inner action-girl tonight on prime-time television.Wipeout Australia pits 20 contestants against the "world's largest extreme obstacle course" with hilarious and embarrassing results - most contestants fall over, slip and even get punched by a machine into a pool of mud.It is hardly the place you would expect to find an upright pastor from Albion Park's Increase Ministries. "I guess I like to think of myself as an action-girl," Ms Riddington said."Plus I have nine brothers and sisters who love Wipeout and I think I wanted to do them proud."I saw the challenge of the big red balls and I thought I could totally do that, but I didn't actually - I stacked it on the second one."YouTube: Watch a clip of Wipeout AustraliaMs Riddington was referring to the Big Balls obstacle, where contestants must leap from the top of one giant ball to another. She says she even called on God's help."With God on my side, I thought I could wipe everyone away," she joked."But I will probably have to eat my words on that one." Nevertheless she's not too concerned by the reaction from the congregation on Sunday."I think there will be a bit of celebrity happening there, and probably a few jokes as well, but I think people will be pretty excited to see one of the pastors on TV," she said.Wipeout Australia airs on WIN at 7.30pm.