© Sunny Stroeer

Unless you’re embedded in the world of high altitude running, climbing and mountaineering, Sunny Stroeer might not be a name you recognise. The German-born endurance athlete and adventurer has somehow flown under the radar despite setting some incredible endurance records. Although she’s previously raced (and won) 100km and 100-mile events, Sunny’s speciality is solo and unsupported high altitude FKTsfastest known time records.

Sunny’s speed records include two separate ascents of Aconcagua – the second highest of the seven summits – one via the ‘normal’ route and the other via the 360 route, a 64-mile journey with 17,000ft of elevation gain which takes trekkers 15-18 days. Sunny completed it in under 48 hours.

She also holds records for Nepal’s 136-mile Annapurna Circuit and China’s 100km+ high altitude TransQilian route, which takes place at an altitude of 10,500ft and includes around 50,000ft of elevation change. Sunny ran it in 20 hours 59 minutes, beating the men’s record by four hours.

A Harvard Business School graduate, Sunny previously worked 80-hour weeks in a high-flying corporate career before quitting in 2015 to follow her passion for climbing and adventure. She now lives out of a converted van with her husband in the US and also runs a mountaineering guiding and high altitude adventure company for women, AWExpeditions. Have a read of our email Q&A to find out more about her backstory and incredible achievements.

© David Clifford

You were a self-confessed couch potato in your early 20s. When did you find climbing and trail running?
I fell in love with climbing and trail running around the time that I graduated from (Harvard) business school at age 25.  I had been running for a few years already, but on the road and at a very low level – not because I loved it but just as a way to stay in shape. I fell in love with trail running when I ran my first 100km trail race in Madagascar which you can read about here.

Can you tell me about your high-pressure career and what prompted you to quit?
I was working as a strategy consultant for Bain & Company.  It was a great learning experience and career opportunity, but I knew from the start that consulting wasn’t my passion – I wanted to be outside. While I was working corporate, I’d pull 60, 70, 80 and sometimes 100 hour weeks from Monday to Friday, but religiously protect my weekends to go on big climbs and runs on Saturdays and Sundays.  I was constantly exhausted and found myself waking up angry at the world more often than not, even though on paper my life looked pretty fantastic.  I knew that I had to make a change, yet didn’t follow through on it until after I went into full-on burnout in 2015 following an incredibly intense 100-hour-week period.

How has your life changed since you embraced van life and followed your passions?
The biggest change early on was that instead of waking up angry at the world, I’d find myself waking up with a huge, silly perma-grin on my face. All of a sudden, the possibilities seemed endless – and that’s still how I feel even though everything is a lot more uncertain.

© David Clifford

You hold some incredible high-altitude FKTs, from Aconcagua to the Annapurna Circuit and TransQilian, but some of these you hadn’t planned or prepared specifically for, is that right?
That’s exactly right.  Some of my favourite FKTs are those that happened not because I’m chasing records, but because I am curious about a place and decided at the very last minute to just go for it.  The Annapurna Circuit is a good example: I was in Nepal with some extra time on my hand and started thinking about hiking the Annapurna Circuit on a Sunday; by Monday afternoon, I was beginning to wonder if I could go for the FKT on the circuit. Less than 48hrs later, I was on my way.

Do you ‘train’ as such or is your lifestyle training enough for your ultra/mountaineering challenges?
Yes to both.  For the most part, my lifestyle creates a great base for me which means that I don’t necessarily have to train specifically for all but the most difficult runs and records. My “season starter” these days is typically 2-3 back-to-back guided or solo climbs of Aconcagua, which creates a great base for the year.

When I do tackle a particularly hard challenge — say, the Ouray 100* (a Colorado 100 miler that includes a proud 43,000ft up ascent) or Nolan’s 14 — I absolutely train and prepare for those; mostly with lots of time of my feet and long, slow days in the mountains.  I am an avid rock climber which is great for cross-training, and I also make time to stretch and do basic bodyweight strength exercises where I can.

*Sunny is too modest to mention that she won the Ouray 100-miler!

© Sunny Stroeer

During your Aconcagua 360 attempt, you experienced mudslides, permit delays and other things which could have derailed your attempt. How did you stay calm and focused?
The FKTs that I enjoy most all come with a lot of uncertainty – that’s the whole reason that they are appealing to me.  The Aconcagua 360 is a prime example of just that: I had no idea what I was going to find, and that was the whole point of the exercise. FKTs for me are about finding out if I am strong and creative enough to solve whatever challenges the run may throw at me; staying calm and focused is not an option in those circumstances, it’s the essence of the thing.

During your attempt, you almost turned around six times above Camp 3. Why, and what kept you going?
The 2-mile stretch between Camp 3 and the summit is, without doubt, the crux of the climb. This is also, unsurprisingly, where I struggled the most: I had already been going, non-stop, for more than 24hrs and I was now at 20,000ft trying to power an ultra-endurance record effort with only about 45% of the amount of effective oxygen that is available at sea level.

To top things off, some of my stashed supplies at Camp 3 had been stolen and I hadn’t been able to eat or make water as was part of my FKT plan. I was physically and psychologically exhausted and ready to give up. Why didn’t I? For two reasons: One, because I knew that I was, yes, incredibly tired but not actually unsafe. Two, because I knew how much work I had put into this attempt and that it was unlikely for me to try it again if I were to give up now.

Do you use any mental strategies during FKT attempts or climbs?
My main mantra is this one: “No stress just training”

© Sunny Stroeer

Have things gone awry on a mountain where you’ve had to think fast to save your own life?
The closest that I have come to dying were two separate moments in rock climbing where I inadvertently took myself entirely off belay in exposed multi-pitch terrain. I’ve also had close calls with serac falls and rockfall, but that’s about it.

How does altitude affect you physically and mentally – are you used to it?
Everything is slower at altitude – movement and thought. I quite like that, and I have come to know well how difficult it is to make forward progress at altitude.  Accepting the handicap of altitude rather than trying to fight it makes the slowness of life up high quite enjoyable.  Just think: even Kilian Jornet took 6 hours for the six-mile yellow-brick-road stretch between Aconcagua’s basecamp and the summit when he set his old speed record there in 2014!

A lot of your challenges/FKTs are solo. Does the solitude enrich your experience?
I do like solitude for FKTs. It makes the problem-solving aspect a bit more acute.

© Sunny Stroeer

Your TransQilian FKT was more ‘organised’ than your usual solo missions and included Chinese pacers who ran with you. Did this change your approach, your enjoyment or your experience in any way?
Yes, it allowed me to be less maniacal about my knowledge of the route (or at least the map) ahead of time. It didn’t necessarily change my enjoyment or my experience, except for towards the very end where I had a crew of half a dozen fresh Chinese pacers who were all happily chattering away in Chinese.  I don’t speak Chinese, and none of my companions spoke English, so I felt quite isolated and alone in my exhaustion while the pacers all got to bond over the shared experience.

What are your must-have items of kit for your FKTs?
Shoes or boots – I actually ran big parts both of the TransQilian FKT and of my Nolan’s attempt in LOWA Innox mid-top boots, rather than low-cut trail shoes. Garmin GPS messenger. Headlamp (I use the Nite Ize INOVO STS). Ultimate Direction Fastpack (between water, food and gear I typically have 10lbs+ on my back). LEKI Microtrail poles.

Have you any sponsors right now?
I am sponsored by GU Energy Labs, LOWA Boots, Ultimate Direction, and West Skincare (or at least I was until COVID hit…. who knows). I also proudly work with LEKI and Nite Ize.

© David Clifford

You can follow Sunny’s adventures via her social media: www.instagram.com/sstoeer and via her website: www.sunnystroeer.com .