Kora development athlete Anna Frost spends her life running the world's toughest trails.
Last year she ran in the Andes, the Alps and the Himalayas as part of a gruelling mountain race schedule, which included eight major races.
She is respected among her fellow runners for her fierce determination, gritting her teeth and powering forward at a point when many would crumble.
Salomon team-mate Rickey Gates has described her as a "raging bull". "A 95% effort does not mean anything to this person," he said.
The New Zealand native, affectionately - and aptly - known as Frosty, tackles everything in life with the same stamina that running at altitude demands.
"I've always had high expectations of myself in everything I do, whether it's running or a personal project," she says.
A life of adventure
Frosty grew up amid the hills of Dunedin, on New Zealand's chilly South Island. Her family were adventurers, often heading off in their bus on treks or camping expeditions.
Her teenage years were devoted to hockey, but at university she started competing in triathlons, half marathons and cross-country races.
It was at the World Mountain Running Championships in Italy in 2004 that she decided to pursue a career as a professional runner, realising it would allow her to indulge her wanderlust.
She has spent much of her time on the road ever since, running in some of the wildest reaches of the planet.
"It isn't just about the running for me," explains Frosty. "It's a life that allows me to see amazing things. Your feet can take you to places a car or bus can't go."
Connecting with the landscape
Frosty likes to arrive a couple of weeks before a big race. It gives her time to forge a connection to the landscape - a vital aspect of her training.
"I like to get to know the mountains, the animals living on it, the plants which grow on it, the local culture," she says. "When I'm running, it's comforting if I know what's coming up next."
On her blog, Frosty's Footsteps, she writes with wonder about the natural beauty she encounters on her runs.
Mountains have a “tremendous energy”, she believes. “When you feel like crap, it's as if they absorb your negativity and power you along.”
Of course they can be scary places too, she says, reminding of her “how small we humans are compared with mother nature”.
When choosing races, Frosty looks for courses which are not only challenging, but visually stunning and physically diverse. She thrives on extremes, whether it’s temperature, topography or altitude.
Heading to the Himalayas
It was these qualities which attracted her to the Everest Sky Race and Manaslu Mountain Trail Race, which she tackled during a two month trip to the Himalayas last year. She came first in both races.
During warmer stretches of the races, the layers were light enough to be carried in her backpack.
"The great thing about wool is it keeps you comfortable even if it gets wet. It's odour resistant too. I only hand washed my base layer a couple of times during a two month trip but didn't get too smelly.”
"It's also really durable - after everything it went through, my base layer still looks like new."
Snowbound on the Everest Sky Race
At the start of the 15 day Everest Sky Race, Frosty joined a group of athletes who'd started running a fortnight earlier as part of an extended event.
"They had broken toenails, wrists, shoes, yet their spirits were still so high," she recalls.
"It was really impressive. I had to do a lot of hard chasing to keep up, particularly as navigation isn't my strong point and I didn't want to get left behind."
The race was diverted by poor weather - at one point, she found herself waist-deep in snow - but she was determined to finish.
"Some days I really suffered, but it took me to new levels. I learned a lot about myself in that race," she says.
Manaslu Mountain Trail Race
Next up was a 212km, seven day part-circumnavigation of Manaslu, the world's eighth highest mountain. It was a very different kind of race, but memorable nonetheless.
"Manaslu is much more untouched than Everest. There were lots of wonderful moments along the way. We slept in a monastery and a little dog followed us for the whole route."
As with the Everest Sky Ride, most of the other participants were non-professional runners, using up their holiday leave to complete the challenge of a lifetime.
Almost half of the 33 Manaslu participants were women - part of a boom in female trail runners that Frosty is keen to encourage. She’s created a forum on her website, Shout It Out Girls, where female runners can discuss issues such as nutrition and adrenal fatigue.
Heading for Hardrock
This year, her goal is to qualify for the 2015 Hardrock 100, an 100-mile ultramarathon in Colorado with 66,000 feet of elevation change.
To qualify, she must first complete her first 100 miler. It’s further than she’s ever run in one stretch, but she is undaunted.
"When running gets tough I just remind myself of what I’ll achieve if I keep going,” she says.
“With trail running, the rewards are literally high - by the end you’re standing at the top of a mountain, enjoying an incredible view of the world."