She has run through the hottest deserts on earth, over the world's two highest mountain passes and clocked up enough miles to span the globe three times but now top ultra-marathon runner Lisa Tamati is facing a completely new challenge - trying to have a baby.
At 47, Tamati is trying to beat a different kind of clock to conceive with fiance Haisley O'Leary.
The couple have attempted IVF treatments and had a heart-breaking miscarriage after 12 weeks of pregnancy.
"I had this wonderful midwife come in," Tamati tells Native Affairs in a programme to screen tomorrow. "She said to me, 'Baby's here in the room with you, baby's spirit is with you, and just let baby go."
The runner is one of an increasing number of older New Zealand women turning to IVF treatment. According to fertility experts, one in four New Zealand women and one in five men experience fertility difficulties by their late 30s.