Kourtney Kardashian puts on a pert display in SKINS spandex leggings while running errands with son Mason

Kourtney Kardashian was certainly dressed for action while out and about with her five-year-old son Mason in Calabasas on Tuesday.

The 36-year-old reality star dressed her petite 5ft figure in a grey tank top cinched over a black sports bra and matching trainers.

The Keeping Up with the Kardashians stunner put on a pert display in her $140 SKINS A400 capri leggings.

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Exercise addict: Kourtney Kardashian was certainly dressed for action while out and about with her five-year-old son Mason in Calabasas on Tuesday

Exercise addict: Kourtney Kardashian was certainly dressed for action while out and about with her five-year-old son Mason in Calabasas on Tuesday

Kourtney finished off her sporty athleisure ensemble with dark sunglasses and a leather baseball cap over her straight raven locks.

Not seen Tuesday were Kardashian's younger children - son Reign, 10 months, and daughter Penelope, 3 - with ex-partner Scott Disick.

On Monday night, the single mother-of-three joined Khloé, Kris, Kim, and Kylie at the Cosmopolitan 50th Birthday Celebration in West Hollywood.

See more news from Kourtney Kardashian and her famous family

Slim and strong: The 36-year-old reality star dressed her petite 5ft figure in a grey tank top cinched over a black sports bra and matching trainers
Slim and strong: The 36-year-old reality star dressed her petite 5ft figure in a grey tank top cinched over a black sports bra and matching trainers

Slim and strong: The 36-year-old reality star dressed her petite 5ft figure in a grey tank top cinched over a black sports bra and matching trainers

Skin-tight: The Keeping Up with the Kardashians stunner put on a pert display in her $140 SKINS A400 capri leggings

Skin-tight: The Keeping Up with the Kardashians stunner put on a pert display in her $140 SKINS A400 capri leggings

Hands full: Kourtney finished off her sporty athleisure ensemble with dark sunglasses and a leather baseball cap over her straight raven locks

Hands full: Kourtney finished off her sporty athleisure ensemble with dark sunglasses and a leather baseball cap over her straight raven locks

While at Ysabel, the half-Armenian socialite flaunted her tiny waist in a belted, black halter jumpsuit - which was in need of hemming.

That same evening, Kourtney's 32-year-old baby-daddy shared an inspirational chalk-written Instagram reading: 'Never give up.'

The preppy 'Lord' Disick spent the last three months partying and canoodling with 18-year-old model Lindsay Vrckovnik as well as stylist Chloé Bartoli.  

Doting mother-of-three: Not seen Tuesday were Kardashian's younger children - son Reign, 10 months, and daughter Penelope, 3 - with ex-partner Scott Disick
Doting mother-of-three: Not seen Tuesday were Kardashian's younger children - son Reign, 10 months, and daughter Penelope, 3 - with ex-partner Scott Disick

Doting mother-of-three: Not seen Tuesday were Kardashian's younger children - son Reign, 10 months, and daughter Penelope, 3 - with ex-partner Scott Disick 

Blowing out the candles: On Monday night, the single mother-of-three joined Khloé, Kris, Kim, and Kylie at the Cosmopolitan 50th Birthday Celebration in West Hollywood

Blowing out the candles: On Monday night, the single mother-of-three joined Khloé, Kris, Kim, and Kylie at the Cosmopolitan 50th Birthday Celebration in West Hollywood

Slimming black: While at Ysabel, the half-Armenian socialite flaunted her tiny waist in a belted, black halter jumpsuit - which was in need of hemming
Slimming black: While at Ysabel, the half-Armenian socialite flaunted her tiny waist in a belted, black halter jumpsuit - which was in need of hemming

Slimming black: While at Ysabel, the half-Armenian socialite flaunted her tiny waist in a belted, black halter jumpsuit - which was in need of hemming

That same evening, Kourtney's 32-year-old baby-daddy shared an inspirational chalk-written Instagram reading: 'Never give up' 

That same evening, Kourtney's 32-year-old baby-daddy shared an inspirational chalk-written Instagram reading: 'Never give up' 

In a preview for the 11th season premiere of KUWTK - airing November 15 - Scott admits that he 'f***ed up.'

'I made the worst decision I've ever made in my life,' the thrice-rehabbed star apologised to Kardashian.

'It's been a really hard time going from, like, having all of you guys to having nobody.'  

Fur coat fun with a teenager: The preppy 'Lord' Disick spent the last three months partying and canoodling with 18-year-old model Lindsay Vrckovnik (pictured) as well as stylist Chloé Bartoli 

Fur coat fun with a teenager: The preppy 'Lord' Disick spent the last three months partying and canoodling with 18-year-old model Lindsay Vrckovnik (pictured) as well as stylist Chloé Bartoli 

All over Chloé Bartoli in Monaco: In a preview for the 11th season premiere of KUWTK - airing November 15 - Scott admits that he 'f***ed up' (pictured in July)

All over Chloé Bartoli in Monaco: In a preview for the 11th season premiere of KUWTK - airing November 15 - Scott admits that he 'f***ed up' (pictured in July)

Kourtney then replied: 'You forget what happens when you're on a binge.'

According to E! News, there's no custody drama and the University of Arizona grad will receive primary physical custody of their children.

'Kourtney still has no interest in getting back with him,' the mag's insider said.

The troubled pair were ironically the only original couple left standing since their E! series originally premiered in 2007.

The thrice-rehabbed star apologised to Kardashian: 'I made the worst decision I've ever made in my life. It's been a really hard time going from, like, having all of you guys to having nobody'

The thrice-rehabbed star apologised to Kardashian: 'I made the worst decision I've ever made in my life. It's been a really hard time going from, like, having all of you guys to having nobody'

Kourtney then replied: 'You forget what happens when you're on a binge' 

Kourtney then replied: 'You forget what happens when you're on a binge' 

No marriage, no divorce: According to E! News, there's no custody drama and the University of Arizona grad will receive primary physical custody of their children (pictured May 23)

No marriage, no divorce: According to E! News, there's no custody drama and the University of Arizona grad will receive primary physical custody of their children (pictured May 23)

'Kourtney still has no interest in getting back with him': The troubled pair were ironically the only original couple left standing since their E! series originally premiered in 2007 

'Kourtney still has no interest in getting back with him': The troubled pair were ironically the only original couple left standing since their E! series originally premiered in 2007 

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