Kourtney Kardashian shows off post-baby abs six months after giving birth

Kourtney Kardashian has been proving that hard work pays off. The mom of three posted a selfie on Instagram showing off her toned abs just months after givingbirth to son Reign in December.

“Hopped up out the bed,turn my swag on Took a look in the mirror said what's up?” the 36-year-old wrotealongside a pic of her in pajama pants and a sports bra.

Showing off her great physique even more, the reality star stopped by the Dash store in WestHollywood on Tuesday wearing tight black overalls that exposed some skin. “MayI get a moment of silence for @kourtneykardash?!?! Yaaassssssssss!!!! Gooff!!!!,” her sister Khloe captioned an Instagram pic of Kourtney in theflattering outfit.

Kourtney's trainer Don Brooksrecently revealed her go-to routine that helped sculpt that six pack."We train anywhere from three to five days a week depending onwhat projects are coming up. [Our workouts last] anywhere from 45 minutes up toan hour," he told E! News.

"The plank is a favorite, but we take it toanother level opening and closing the legs like scissors while at the same timeraising and dropping the hips! So not only are you strengthening the core butalso triming the hips, thighs and waist. [We also do] the trunk twist alongwith a back row using the bands. The benefit of this exercise will give youflat abs and coke bottle obliques while removing those fat handles from theback and arms."

The eldestKardashian also credits clean eating to her success and often posts photos ofher healthy meals.