Brooke Shields Hit 'Another Plateau' in Her Recovery from a Broken Femur: 'A Lot of Weakness'

Victoria Stevens Brooke Shields

Brooke Shields is healing from her harrowing leg injury and staph infection, but lately, it feels like she's stuck.

"I'm on another plateau," the 55-year-old actress tells PEOPLE of her recovery process when we caught up with the star for her partnership with EltaMD. "I'm now with no crutches and no cane, and I'm starting to work out again. But … there's bone soreness and there's a lot of weakness."

Shields is making strides, though, in physical therapy.

"I'm able to stand on that leg fully and balance, and I'm getting all of that back and just kinetically getting more connected again and reeducating all of my muscles to fire appropriately again," she says.

"It's been a lot of work, though," she continues. "You really have to do it every day and you have to have a mindset because it can be very frustrating."

RELATED: Inside Brooke Shields' Terrifying Accident and Her Struggle to Walk Again: 'I'm a Fighter'

The Suddenly Susan star has learned that the recovery process is slow, and that she needs to have patience.

"I now know that, okay, it's going to take a while for me to be able to fully be as strong as I used to be," she says. "But every day it's a little bit better and I'm beginning each day to start fresh."

RELATED VIDEO: Brooke Shields on How She's Doing After Suffering From a Broken Femur

Shields likens her healing process with her leg to when she learned eight years ago that she had a precancerous spot on her skin that had to be removed. Her injury felt insurmountable at times, but she's been able to slowly improve.

RELATED: Brooke Shields Shares Photos from Her 'Excruciating' Accident: 'The Journey Is Just Beginning'

With sun damage, "You get really frustrated because it's considered damage and you think, 'Oh, I've already done it,' but it's never too late to start protecting your skin," she says.

The mom of two learned to be "vigilant" about applying sunscreen and taking care of her skin after that scare.

"That was just a very scary diagnosis and the fact that it had to be actually cut out of my lip is a terrifying situation to find yourself in," she says. "That's when I started incorporating [sunscreen] into my daily routine, not just bringing it with me on vacation or in the summer."

Shield emphasizes that "preemptive, preventative" care for your skin "is really important."

"We don't necessarily think in those terms, preventative," she says. "I mean, especially for my children, they don't think anything about a future. They just think about themselves in the present now and trying to teach them things like exercise, things like sun protection. And all of those things that we moan and groan about are actually serving you for the future."

Shields' every day routine includes three go-to products: UV Restore Broad-Spectrum SPF 40 for her face, UV Active Broad-Spectrum SPF 50+ for body and UV Lip Balm Broad-Spectrum SPF 36 for lips.