"Gotta get it in... #workinonmyfitness #gymtime #cardio #thereIamwithnomakeupagain! Lol," she captioned a shot of herself looking fresh faced with her hair pulled back in a messy ponytail.
While the 46 year old's makeup-free face is truly envy-inducing, what really caused jaws to drop were her washboard abs, which she flaunted by wearing a hot yellow sports bra and matching black-and-yellow yoga pants in the steamy selfie.
Perhaps it was the birthday cake that inspired J.Lo to hit the gym extra hard on the 23rd!
Just hours before she took to Instagram to show off her bod, the multi-hyphenate posted a photo of herself celebrating her twins' 8th birthday with a giant cake.
"HAPPY BIRTHDAY TO THE LIGHTS OF MY LIFE," she captioned a photo of herself with her arms around her "coconuts" Emme and Max -- whose father is Jennifer's ex-husband, Marc Anthony -- as they blew out the candles on their cake.
"You have brought me nothing but joy and happiness since the very second you were born," she continued. "I am so proud of who you are and the beautiful loving caring people you are growing into. #coconuts8thBirthday. #Iloveyoubeyondforever #maxandemme #February22nd And Thank you everyone for all the beautiful birthday wishes and videos. They are so precious!!"
J.Lo's babies may be growing up before our very eyes, but their mama has clearly stumbled upon the fountain of youth!
This isn't the first time the "Shades of Blue" star has gone makeup-free on Instagram in 2016 -- or posted a too-cute photo of her twin kiddos.
She accomplished both tasks in January while celebrating the birthday of her longtime manager, Benny Medina.
In the sweet shot, Jennifer appears makeup-free in a white bathrobe with a towel wrapped around her head.
Emme and Max may have just turned 8 years old, but they're already dead ringers for their famous folks. Did those kids hit the genetic jackpot or what!