Taylor Swift reportedly encouraged Lena Dunham to hire a personal trainer.

Taylor Swift and Lena Dunham

Taylor Swift and Lena Dunham

The 'Blank Space' hitmaker is said to have urged the 'Girls' star, who recently admitted she is "on a little bit of a physical fitness kick," to start working out on a regular basis in a bid to feel healthier.

A source told Star magazine: "Lena has really confided in Taylor about her insecurities. And Taylor was sympathetic at first but finally got tired of Lena's constant pity party and told her that if she was so unhappy with her weight, she needed to get a trainer and do something to make a change."

Meanwhile, the 28-year-old screenwriter recently confessed she was overhauling her lifestyle because she was fed up of being unfit.

She told David Letterman: "Part of the reason I wanted to do it was because I was losing my breath when I walked up a stair."

Lena admitted in her memoir last year that she once ended up in hospital after embarking on an extreme diet in a bid to lose weight before she first started shooting her HBO series.

She later said: "My food intake was a hard thing to share publicly. A lot of my life and work is sort of about not succumbing to [those pressures], so it's a little painful to go, 'Oh but look, there was a time where this dominated every moment of every day.'

"It was basically revealed that I'd been just drinking laxative tea and coffee and smoking cigarettes and then eating weird foods at weird hours. I really messed myself up."