Reality star Rob Kardashian celebrated his 26th birthday at 1 Oak Nightclub in Vegas on Friday

He has been spotted out hiking more than partying of late, as he battles to shift the 50lb he piled on whilst dating British singer Rita Ora.

But on Friday Rob Kardashian was out in force as he celebrated his 26th birthday with friends in Vegas.

The reality star looked portly in his all black get-up, wearing black leather trousers with a black shirt over a black T-shirt and black training shoes.
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Birthday boy: Reality star Rob Kardashian celebrated his 26th birthday at 1 Oak Nightclub in Vegas on Friday

The only splash of colour was in the reality star's chains around his neck, and his bracelet and watch.  And of course his tattoos.

 

Rob's publicity-friendly mother joined him on the red carpet for a photograph opportunity, but the sock designer's famous sisters were nowhere to be seen.

Pregnant Kim did tweet to show her support, sharing a photo of her brother's sock promotion club night with the caption "So excited for Rob!," earlier that day.

Motherly love: Kris Jenner posed with her son as they entered the 1 Oak Nightclub for his 26th birthday celebrations

Happy birthday to you: Kris presents her son with a designer birthday cake at the Vegas hotspot

After the sock promotion, Rob shared a picture of his group arriving at 1 Oak Nightclub in the Mirage Resort and Casino to celebrate his turning 26, tweeting: "TURN UP CHUCK! VEGAS."
The Keeping Up With The Kardashian star, who jokingly referred to himself as "fat boy Rob" is on a health kick to ditch the weight he gained ater his breakup with British singer Rita Ora.

Since he embarked on his 60-day health kick hikes have become a daily part of Rob's routine.

Hello boys! The reality star's mother posed with his friends on the red carpet

Rob shared a picture of his friends arriving at the Vegas club, saying:"TURN UP CHUCK! VEGAS"

The 25-year-old - whose birthday is coming up on Sunday - has been spotted hitting the walking trails around Los Angeles as he battles to loose 40 pounds.

The significantly heavier reality star has claimed his relationship breakdown with British pop singer Rita Ora caused him to put on the extra weight.

Since their split at the end of last year, Rob has openly acknowledged his weight gain posting pictures of his diet food on Twitter declaring it the 'fat boy diet'.

Are those for you? Rob handled some wildly patterned socks during an appearance at Kardashian Khaos in Las Vegas on Saturday

For the fans: The birthday boy tagged his name on a pair of socks for a fan

This week Rita finally talked about the relationship, saying she feared it might have ruined her career after Rob said on Twitter she had cheated on him with 20 men.

The 22-year old told Look: 'I don't vocalise things that don't deserve attention. But it was something that was so unnecessary. Why would you flood people's brains with unnecessary s**t?

'Twitter... can ruin your life. I thought I nearly had a 'ruined' moment, but no.

Long wait: Dozens of fans piled outside the store to catch a glimpse of Rob

Mama's boy: Rob was joined by his mother Kris Jenner and family friend Cynthia Busey

Whose party is it? Rob's mom looked more excited to be there

'When you're involved with someone for a while and they decided to express their feelings to the public - that's not my personal way of therapy, but I guess everyone takes split-ups differently.'

But while Rob took the break up hard, he seems to be doing a lot better and has been spotted out at some of Hollywood's top clubs recently.

On Wednesday night Rob was seen at the Emerson nightclub wearing what looked like the same black leather trousers, reminiscent of those favoured by his soon to be brother-in-law Kanye West.

The ex: Rob said his weight gain was caused by heartache after his split with British singer Rita Ora