06/23/2012 at 01:00 PM EDT
Lately, Jessica Simpson
has been working up a sweat (and rocking some serious workout gear
) as part of her post-pregnancy weight-loss plan
Not that she seems to be anything but comfortable in her skin – hot momma alert!
"Just taking a walk around the block," she Tweeted
Friday, alongside a rather revealing snapshot
– is that a pedometer in her cleavage? "Street legal???"
Since welcoming daughter Maxwell Drew
with fiancé Eric Johnson
May 1, Simpson, 31, hasn't shied away from talking about her post-baby, um, assets.
"She latched on at the very beginning. Nursing is a full-on job," she previously told PEOPLE
of breastfeeding. "Sometimes I worry she's not getting enough, but it's been an amazing experience."
Simpson added: "It's the worst if I have to pump and give Eric a bottle to give her. I miss holding her and having that closeness."
For now, her fitness motivation doesn't have much to do with the scale – or showing off those curves at the beach.
"It would be nice to feel comfortable in a bikini, but that's not my goal," Simpson, who is working with Weight Watchers
to get back in shape, told PEOPLE. "I just want to fit into jeans!"