Niall Horan poses topless for gym workout as One Direction lads start gruelling fitness regime

The singer wants everyone to see his muscles as the boyband remain focused on bulking up and working out.

They spend most of their time on tour , singing a few pop songs, playing computer games and binging on fast food.

So it was only a matter of time before the One Direction lads bucked up their ideas and signed up for gruelling work-out plans.

The boyband have even started a relentless routine with mixed martial arts trainers as they hope to bulk up for the US leg of their Take Me Home tour.

While we are mostly familiar with seeing them dressed like someone has been kicked through Topman covered in sticky tape, Niall Horan was showing off his new found frame.

The Irish hunk , 19, posed topless for a picture in the middle of a gym routine as he straddled the weights machine which focuses on strength of the shoulders and back.

Niall makes no secret of he loves 'having the craic' and 'some pints' with his boys back home when he can squeeze in some time off.

But he will no doubt be enjoying his time off from the UK as the singers travel the world performing for tens of thousands of fans.

The time away from the UK will help the lads focus on their gym training and healthy eating.

Liam Payne, 19, has even been taking protein shakes to help build up even more muscle.