Justin Gelband's motto is "there's no quick fix." At his downtown Manhattan fitness studio, he teaches a magical combination of Pilates, yoga, and calisthenics known as ModelFIT. It works the small muscle groups in order to build strength rather than bulk. So do you know what a Victoria's Secret Angel looks like? Yeah, he basically built that.
Goddesses like Candice Swanepoel, Behati Prinsloo, Karlie Kloss and Lily Aldridge swear by his training.
He says, "cut out the hour plus cardio sessions and focus on 30 minutes of intervals every day. For example, if you are working out on a treadmill, where jogging is at 6.0 and running is 7.5, do a minute at 6.0, a minute at 6.1, a minute at 6.2, up till 7.5 then reverse back down. Whatever you do, do not sprint."
To read about his specific exercise routines that you can do at home, read his interview on how to target specific muscle groups.