Michael Trisler was a stunt coordinator, stuntman, and actor on Lost. He played Juliet's father in the episode "The Incident, Part 1". He was also a stunt double for Josh Holloway in scenes such as when Claire's house explodes in "The Shape of Things to Come", and in "The Substitute", when Sawyer falls down the side of the cliff on the rope ladder. 
Trisler can be seen on the Season 5 DVD "Lost On Location" featurette for the episode "The Lie" discussing the making of the flaming arrow attack.  He can also be seen on the Season 6 DVD "Lost On Location" for the episode "The Substitute", performing the cliffside fall, and "Happily Ever After", driving Desmond's car into the pier and coordinating Henry Ian Cusick and Dominic Monaghan's underwater scene.