Not a day goes by without Nicole Richie hitting the gym. We have to admit, her body is looking fit and fabulous ... SO much different from her Simple Life days.

Harlow and Sparrow's mom, who used one of her many pricey purses as a workout bag, walked out of her Studio City gym holding on tight to her green juice.

So that's her secret to staying so slim. Way to stay dedicated, Nic!