10/22/2012 at 04:30 PM EDT
They say if you've got it, flaunt it – and Jennifer Lopez
did just that.
The mother of twins exposed her enviable abs while out and about in London on Monday with boyfriend Casper Smart
Clad in a tight-fitting cropped black top with black pants and a long, gray coat, the physically fit star
, 43, strolled alongside her man, who was also dressed in a similar color scheme.
Lopez worked hard with trainer Tracy Anderson on a custom routine that targeted the area from the singer's abs to her hips.
"We don't want her natural beauty to go out of balance," Anderson told PEOPLE
over the summer. "[Overly] ripped abs would ruin her look."
In the end, Lopez "loves the results," according to Anderson.