This means that rather than hanging on the the cable that hangs from the zip lines, she is well balanced and hanging from the clip on the harness that is strapped around her waist, over her shoulders and around her legs.
My wife, Julie, left a comment to my photo yesterday mentioning that she rode down zip lines "Super-Chica" style. That means that she was lying down face first, with her arms and legs extending out, flying through the jungle like Superman. How did she remain in that position? She explained to me (as I was not with her on that trip), that the guide was very nice and allowed her to wrap her legs around him as he rode down behind her to keep her horizontal. My wife is a 6-foot tall blonde. I am sure it was a big sacrifice for the guide to escort her down the zip lines by allowing her to wrap her legs around him.
the above photo also shows the platform that is at the other end of this link in the zip lines. That is where she will land. This rider was one of three young women from New York (one of whom was British) who were vacationing in Costa Rica and who went down the zip lines with my two sons and me.