Dr. Natalia Petrzela is an author and fitness instructor who says she has noticed many “cult vibes” in the fitness world. She says that charismatic instructors, special treatment of certain students in fitness classes, and a lack of physical boundaries can all be warning signs that something isn’t right. Even the ambiance of a room can set the stage.

“[It’s] somewhere between a séance and a nightclub. Candles, incredible music, gorgeous people – it’s very intoxicating,” says Dr. Petrzela.

Watch the video above to hear Dr. Petrzela describe one experience when, she claims, an instructor once gave her a “spin class lap dance.”

This episode of Dr. Phil, “Cult Vibes?” airs Wednesday.Check your local listing for air times.

Dr. Natalia Petrzela is the author of “Fit Nation: The Gains and Pains of America’s Exercise Obsession.” Available wherever books are sold.

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