The 19-year-old's Pilates instructor, Mari Winsor, said that Cyrus has been training hard for the last four months, rather than dieting and that is the reason she has been sporting a particularly slim and toned body, reported Contactmusic.
"I think people need to chill out. She's healthy and she feels good, that's the main thing. She's smart about her body. She wanted to sculpt her body, that's all," said Winsor.
"Miley's toned physique is the result of a gluten-free diet and daily Pilates classes. I wanted to get her shoulders down and get her to relax her upper body. If you notice, her posture is a lot better. She works hard. When this girl comes in, she is on fire. She's focused," she added.
Cyrus got engaged to actor Liam Hemsworth on May 31. She is already planning her nuptials.
"Nothing has been definite yet. She's just pretty much brainstorming everything about her wedding. I know she wants to have a summer wedding, something on the water maybe," a source said.