"I suggested we get one... It's a relatively new thing in the industry, and obviously there is a great deal of intimacy on our show," he told Digital Spy.
"In a way, it had kind of been left to Catriona and I to just sort of work our way through [sex scenes]. Obviously we have got a way of working and we have created this relationship, but also we realised quite quickly when she came on board that actually, it's a lot of pressure and she really helped us work through those scenes.
"She also helped maybe move the scenes on and maybe add more to them that maybe we didn't know how to do in the past, so it has been a really welcome addition I think, also for the younger actors that also have to do intimate scenes. It just takes out a lot of the pressure and fear and hopefully makes those scenes more enriched."
Sam also revealed that part of bringing someone new on board to coordinate the sex scenes was to benefit younger actors, Cesar Domboy (Fergus) and Lauren Lyle (Marsali).
"When Outlander started we were in a different time, our show was a lot more explicit in some ways than it would be now," he said. "I think our show is very challenging in those scenes... it can be hard for an actor to navigate.
"So I felt responsibility to support our cast, and the crew as well and the writers, so we now know what the boundaries are, and also how to explore those."
"When we first met, we had to dive into these really, tough and intimate scenes," Sam said. "That's made our relationship a lot deeper and we feel comfortable with each other now. It really bonds you. It's like a marriage... almost."
Outlander Season 6, Episode One is now available to watch on Foxtel and BINGE with new episodes dropping weekly.
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