Rihanna wowed the celebrity world with her sleek figure-hugging Armani dress at the Grammy Awards on Sunday (February 12, 2012), and fans were immediately anxious to discover how she managed to fine-tune her attention-grabbing physique for the awards show.

Harley Pasternak, 'creator of the 5 Factor Program' is the man behind Rihanna's svelte figure, and he dished to People magazine about getting the Barbadian beauty into shape, saying she does her best to squeeze in at least three workouts a week, each lasting for around 25 minutes. Harley explained, "She's got such a beautiful body naturally.With someone like her, it's about the fine tuning.She's been really focused and stepped it up increasing her sessions to five days a week and bumping her cardio to a total of 30 minutes a day from 10". The fitness trainer says cycling is an important part of Rihanna's regular cardio routine, as well as basic exercises such as jumping a rope or stationary jogging. As for a diet, Pasternak says the R&B star does her best to stick to five small meals a day but still "gets salty cravings" and therefore eats plenty of high-protein bean-based 5 Factor chips, adding, "They've been a big hit with our music and entertainment clients".

A respected Hollywood fitness guru, Harley's clients include other stars of the stage including Katy Perry and Lady GaGa.