Viewers accuse him of injecting an even more dangerous substance

Admits to using steroids but says he is proud of his body

Man - know only as Valdir - flexed his huge pecs on

A man has appeared on Portuguese TV to show off his whopping muscles as part of an 'extreme body' competition.

The bodybuilder known only as 'Valdir' explained how he was fed up with people joking about how thin he was, and so he decided to bulk up.

However Valdir's inflated pecs, traps and biceps have come under fire from viewers, with many accusing him of using a dangerous muscle-enhancing drug.

A man - known only as Valdir - has appeared on a Portuguese TV show, flexing his 'extreme' muscles

The man explained how he decided to transform his body in response to taunts over how thin he was

His bulging biceps do appear out of proportion with other parts of his body, leaving many viewers speculating.

In the short segment, which appeared on Portuguese TV show A Transformação Mais Incrível (which roughly translates as 'amazing transformations'), Valdir makes his muscles dance at the request of the host, and shares his reasons for wanting to transform.

According to YouTube commentators, who translated for English-speaking audiences, Valdir reportedly said that he is very happy and proud of his body.

'He says he does not recommend it to anyone as well, but he loves it, that's why he does it,' one explained.

'He wanted to get big so he also used anabolic steroids and actually wants to get even bigger, especially in the legs.'

However viewers weren't convinced, with many accusing him of injecting a substance called Synthol.

Valdir apparently admits that he uses steroids as well as lifting weights, and says he's proud of his body

Viewers of the show have their doubts and suspect that he is using a more dangerous enhancer, Synthol

This 'site enhancement oil' can be used to mimic the appearance of developed muscle where in fact it is lacking.

It is not restricted but when injected the user risks pulmonary embolisms, nerve damage, infections, strokes, ulcers and cysts.

Bodybuilders have been known to die prematurely from muscle enhancement drug-related diseases.

According to the show's website, Valdir was competing in an extreme body contest, and was up against Dona Lavina, a woman with massive fingernails.