Jessica Alba 'starts post-baby workout routine'

Jessica Alba has started working out again less than three weeks after giving birth to her second child.

The Spy Kids 4: All the Time in the World actress and husband Cash Warren welcomed daughter Haven Garner on August 13.

"I did my first day of workout since I had the baby. Just cardio for 40 minutes. My doc told me I could start after 2 wks. I'm going light, stationary bike and elliptical," Alba wrote on her Twitter page last week.

The Little Fockers star also gave advice to several of her followers on how to shed their pregnancy weight, adding: "I would keep your diet as healthy as possible 6 days a week and give yourself one day to indulge.

"Start with walking and throw in 3 sets of lunges 20 per leg. Your could do it while strolling your baby."

She and Warren are also parents to a 3-year-old daughter named Honor.

Alba recently insisted that she will not allow her children to become involved in the film industry and work as actors until they are adults.

Watch the trailer for Spy Kids 4: All the Time in the World below: