Jessica Biel Baby Weight Loss: Trainer Dishes On How The Celebrity Mom Lost The Pounds

When it comes to keeping fit, actress Jessica Biel has the habit and activity down pat.

Even before getting pregnant, she has been used to doing rigorous workouts, according to Mail Online. Then, just four months after giving birth, she has easily bounced back into her slim body, all thanks to the help of her personal trainer, Jason Walsh.

Walsh said that before the pregnancy, the actress worked out with him for four times a week. However, the pair switched to a slower pace after Jessica gave birth and nursed her baby Silas.

"I don't want to stress her out too much," Walsh told E! and said that they've been working out two or three times a week on average. "We can do enough to progress and get back into it."

Walsh understands why setting the pace for a new mother like Jessica is important. "Mothers, after having the kid, they really need to pay attention to the breastfeeding and stuff like that. She can't really lose everything 'cause she is breastfeeding. It's going to take a while," he told the news outlet.

To help the actress, Walsh made her get on VersaClimbers, a machine that simulates climbing exercises. The trainer said this works perfectly for mothers who have just had babies. "The great thing about the VersaClimber is its super safe. It's a natural motion; it's a crawling motion. We're all born with it. It's low-impact. It reinforces proper movement patters [sic]. It's the upper and lower body. I'ts huge cardio or conditioning impact. Metabolically speaking, it incinerates calories more than anything else out there," he went on.

The machine will be part of the equipment his clients may use in his new fitness studio in West Hollywood called Rise Nation and it is understood that this is where Jessica does her workouts with her trainer, "At least here, we aren't doing too much. She can kind of go at her own pace and it's fantastic."

A known fitness buff, Jessica's workout routine back in 2010 was more complicated. "I like to do a couple of classes of yoga during the week, mixed in with weight training sessions, which are for strength. Actually the yoga class is less about strength and more about stretching and elongating, so I can have the combo," she told Glamour. She also loved hiking and was occasionally seen doing the activity with her husband, Justin Timberlake.