Hilary Duff Works It Out in Studio City

Hilary Duff bundles up in a warm cardigan as she walks to the gym for a workout on Tuesday (December 14) in Studio City, Calif.

The 23-year-old actress is back to the grind after a relaxing trip to Palm Springs earlier this month with sis Haylie and pal Sommer Terry.

“Oh my lordy! Is the colony palms hotel in palm springs heaven on earth?I think YES!that was so beautiful! A much needed vacay with the girls,” Hil tweeted.