'Getting the Ballet Body back!': Mick Jagger's partner Melanie Hamrick, 29, tones up with a -100c blast of nitrogren... after welcoming baby son with Rolling Stones rocker, 73

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She welcomed a son named Deveraux Octavian Basil with Rolling Stones frontman Sir Mick Jagger, 73, earlier this month.

And ballerina Melanie Hamrick, 29, has wasted no time in getting back into shape, kicking things off with a Cryotherapy session - just three weeks after giving birth.

The bizarre treatment involves exposing the body to nitrogen gas at minus 100c temperatures for up to four minutes.

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Post-baby regime: Ballerina Melanie Hamrick, 29, underwent a bizarre Cryotherapy session - just three weeks after giving birth to a baby boy with Rolling Stones rocker Sir Mick Jagger, 73

The extreme cold is said to boost metabolism, aiding weight loss.

Melanie can be seen giggling as she poses nude in a furturistic pod mid-treatment.

'Day one of my journey to getting the Ballet Body back! Thanks @kryolife for the Icy start! #ballerina #kryolife #balletbody #postpartumfitness #postpartumbody #fitness @abtofficial', she captioned the image. 

She also shared a snap of herself back in the ballet studio, looking the picture of health and fitness.

'Gym day for a baby workout! @abtofficial #ballerina #fitness #nike #flexistretcher postpartumbody #3weekspostpartum', she shared. 

'I'm so love with my baby Deveraux Jagger': Thrilled Melanie shared a snap of her newborn son with Sir Mick Jagger on Instagram last week 

'Gym day for a baby workout!': The dancer also shared a snap of herself back in the ballet studio, looking the picture of health and fitness

Last week, Melanie treated her followers to the very first snap of her baby son. 

Taking to Instagram, she wrote: 'I'm so love with my baby Deveraux Jagger. Thank you @lizzyjagger for the sweet introduction.'

The picture is very similar to the one first shared with Mick's daughter Elizabeth two days ago.  

The baby's full name is Deveraux Octavian Basil Jagger - Octavian means 'born eighth' in Latin.

A photograph of the baby, Sir Mick's eighth child, appeared on an Instagram account under the name of Elizabeth Jagger, one of the Rolling Stones rocker's other children.

The caption read: 'My beautiful baby brother Deveraux Octavian Basil Jagger.'

Mick's daughter Elizabeth posted an almost identical first picture of the newborn boy on Instagram on Friday

Basil was the first name of Sir Mick's late father, who died in 2006, although he was known to others as Joe.

Sir Mick became a father again at the age of 73 on December 8, with his partner Melanie Hamrick, 29.

Elizabeth, commonly referred to as Lizzy, is followed by more than 50,000 people on her social media account, although it is not verified.

Sir Mick, who is a great-grandfather, has six other children as well as Lizzy and his one week-old son - Karis, Jade, James, Georgia, Gabriel and Lucas - from previous relationships.

Their ages range from 17 to 46.

Baby joy: Rolling Stones frontman Mick (right) has become a father again at the age of 73. He welcomed the latest addition to his brood with Melanie (left)

Sir Mick and Ms Hamrick began dating after the death of fashion designer L'Wren Scott in 2014, Sir Mick's partner of 13 years.

A representative for Sir Mick has been contacted.  

It is understood Sir Mick flew 3,500 miles from London to New York in a last-minute dash to be by Hamrick's side for the birth.

A source told the Daily Mirror the legendary rocker said he 'needed to be there' for his partner.

The source added: 'He made sure he was there. He wouldn’t have missed it for the world.'

A statement from Sir Mick's publicist said: 'Melanie Hamrick and Mick Jagger's son was born today in New York and they are both delighted.' The couple are pictured together in May 2014

A statement released on behalf of the couple said: 'Melanie Hamrick and Mick Jagger's son was born today in New York and they are both delighted.

'Mick was at the hospital for the arrival. Mother and baby are doing well and we request that the media respect their privacy at this time.'

The news comes after it was revealed that the Rolling Stones are on course for this week's UK Number One album. 

The rockers’ latest LP ‘Blue & Lonesome was way ahead in the midweek charts.

Sir Mick is understood to have given Melanie a $150,000-a-year maintenance deal to help the ballerina raise their child.

He is also believed to be helping the New Yorker find a home in the US to raise the boy.

Jumping for joy: Sir Mick is understood to have given Melanie a $150,000-a-year maintenance deal to help the ballerina raise their child

The $150k will be paid until the child is 18, with school fees also paid for. After secondary school a trust will help cover further education and expenses, which could be as much as £500k. 

Even though Mick and Melanie are not planning on getting married, they plan to co-parent given his hectic work schedule. 

A source told MailOnline: 'Mick wanted to make sure that the deals and money aspects were in place before Christmas and the birth of their child.

'Mick is adamant that the kid will be cared for and the deal works out at 150k a year and then housing on top of that.

Elegant: The singer and 29-year-old ballerina Melanie Hamrick welcomed a son, Sir Mick's eighth child, in the latest addition to his brood

​'​It is a very fair deal for family to make sure they have adequate care and finances, and of course Mick is keen to help raise the child. Mick insists that he will be stand by Melanie throughout the child's first 18 years. 

'After that they will make sure that the child's future is provided for too whether it be a career or seeking further education. This is a very amicable deal which has been agreed between a couple, who are not married, but are devoted to doing the right thing for the child. 

'​Mick is excited about the shows and has found a new found love for the band again. 

'They will be pushing their new blues album out too during much of 2017. He is very excited about things that are happening with the band.' 

Sir Mick has a daughter, Karis Hunt Jagger, 46, from his relationship with Marsha Hunt and a daughter Jade Jagger, now 45, with his ex-wife Bianca.

He had four children with his ex-partner Jerry Hall - Elizabeth, 32, James, 31, Georgia, 24, and Gabriel, 18.

He also had a son, Lucas, 17, following a brief relationship with Brazilian model Luciana Gimenez.

Their liaison ended Sir Mick's 22-year-relationship with Hall, who is now married to media mogul Rupert Murdoch.

Legends: Rolling Stones frontman Sir Mick Jagger (pictured third from the left with bandmates Charlie Watts, Ronnie Wood and Keith Richards) has become a father again at the age of 73

Sir Mick has five grandchildren and became a great-grandfather in May 2014 when Jade's daughter Assisi gave birth to a baby girl.  

The new addition is Sir Mick's eighth child, and his first with Ms Hamrick.

Sir Mick and Ms Hamrick began dating after the suicide of fashion designer L'Wren Scott in 2014, Sir Mick's partner of 13 years.

The baby news comes six months after his bandmate Ronnie Wood's wife Sally Humphreys gave birth to twin girls, just two days before Wood turned 69.

In an interview given by Wood a month after the birth of his daughters, Wood revealed that Sir Mick was one of the first people to meet them.

He told Hello! magazine: 'Mick popped in on the third day. He couldn't wait to see them, I put one in each arm and took a photo.

Moving on: Sir Mick and Melanie (right) began dating after the suicide of fashion designer L'Wren Scott (left, with the Rolling Stones legend) in 2014, Sir Mick's partner of 13 years