It's Superboy! Ten-year-old is seriously ripped with bulging muscles due to rare condition that causes muscle overgrowth

A ten-year-old Vietnamese boy named Nguyen Hoang Nam already has the build of a professional bodybuilder, due to a condition that causes muscle overgrowth.

The Herculean youth was found flexing his muscles and playing with friends in Trang Bom, a small township on the outskirts of Bien Hoa, on Wednesday. 

'Since he was born, he's always been really gentle. He gets on well with his friends,' said Nam's father. 

Nguyen Hoang Nam, a ten-year-old boy from Vietnam , has Myostatin-related muscle hypertrophy - dubbed 'superman syndrome' by Vietnamese media 

Superman syndrome is characterised by reduced body fat and increased skeletal muscle size. Pictured: Nam stands next to a friend of around the same age

Nam's father said that when his son saw him training, he would often imitate him. Pictured: Nam arm-wrestles his father at their home in Trang Bom, a small town on the outskirts of Bien Hoa, Vietnam

'When he saw me training, he often imitated me. When he was younger, most kids borrowed phones to play games, but he borrowed mine to watch body builders.' 

Doctors diagnosed Nam with Myostatin-related muscle hypertrophy - dubbed 'superman syndrome' by Vietnamese media. 

'My dream is to become a body builder in the future, because I saw the body builders on YouTube, and they looked really nice and professional,' Nam said. 'I admire them a lot.' 

Nam says that it his dream to become a bodybuilder, with his father saying that while children his age are borrowing phones to play games, his son was borrowing his phone to watch videos of body builders on YouTube

Individuals with Myostatin-related muscle hypertrophy have up to twice the usual amount of muscle mass in their bodies, but it does not always equate to an increase in strength

When stood next to a boy of a similar age to him, it is clear how defined Nam's muscles are

A video of Nam with his friends and family sees him showing off his muscles and his ability to do headstands

A video of Nam with his family and a friend see him showing off his muscles. 

Standing next to his friend, it is clear how much more developed his muscles are compared to those of a similar age without superman syndrome.

The video also shows him arm-wrestling with his father, and later demonstrating his ability to do headstands. 

'Superman syndrome' is not known to cause medical problems, and affected individuals are intellectually normal - but they can suffer from stuff muscles

Another characteristic of 'superman syndrome' is that muscles can get very tight. Nam's parents encourage him to do martial arts and yoga in order to relax his muscles so they do not get too stiff

The condition is rare, and is also characterised by reduced body fat, and while it increases the skeletal muscle mass by up two twice the amount, it does always equate to increased strength.

Myostatin-related muscle hypertrophy is a rare genetic condition that is caused by mutation in the MSTN gene.

The MSTN gene tells the body how much myostatin to create, which is active in skeletal muscles for movement, and also restrains muscle growth so they do not grow too large.

'My dream is to become a body builder in the future, because I saw the body builders on YouTube, and they looked really nice and professional,' Nam said

The syndrome is caused by a mutation to a gene that controls the amount of myostatin in muscles. Myostatin normally limits muscle growth, but when the body produces less, muscles can become overgrown

However, mutations in this gene that reduce the production of functional myostatin leads to an overgrowth in muscle tissues, as seen in Nam's case. 

While the condition reportedly does not affect the boy's overall health, 'superman syndrome' does make him suffer from muscle stiffness and a lack of flexibility. 

His parents encourage him to do martial arts and yoga in order to relax his muscles so they do not get too stiff.