The singer hits the gym

Niall Horan is working hard on his fitness again following his knee operation in January.

The Irish star headed to the gym on Friday ahead of the first show on One Direction‘s Where We are Tour in Bogota, Columbia but unfortunately ended up feeling a bit queasy.

First session back with jarvis! Knee feelin ok!’ Niall, 20, posted on Instagram with a photo of him on an exercise bike.

Threw up because of the altitude , me and Jarv called it #altitudeoosshhh’

Luckily Niall soon recovered and enjoyed being back on stage again.

Bogota ! That was incredible! Thank you so much! loved every second of it,’ the singer wrote on Twitter after the concert.

Niall was able to enjoy a bit of downtime on the weekend and yesterday allowed bandmate Louis Tomlinson to decorate the scar on his leg.

Haha @louis_tomlinson decided he was gona colour in my scar ! Looks mad,’ Niall posted with before and after pictures.

Louis, 22, scribbled a long arrow over the wound, making it look like a tattoo.

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Anna Francis