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    The Gym Class, Reinvented

    Photo by: Courtesy of Equinox
    Equinox-
    CITY: New York, Chicago, Los Angeles
    
CLASS: ViPR

    
What distinguishes this class is its primary tool, a large rubber cylinder (known as a ViPR) that is ... more 
    Photo by: Courtesy of Equinox
    Equinox-
    CITY: New York, Chicago, Los Angeles
    
CLASS: ViPR

    
What distinguishes this class is its primary tool, a large rubber cylinder (known as a ViPR) that is said to be the "evolution of free weights."

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    Wed, Oct 12, 2011 2:05 AM EDT
    By Ryan Halverson, DETAILS Health clubs and trainers are embracing the intense half-hour session. Here are the best group-fitness options.