What it’s like climbing to 4,300m (as a lowlander who hasn’t acclimatised)

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It’s most of a decade since I first heard about John Summerson’s book, The Complete Guide to Climbing (By Bike). This catalogue of the USA’s greatest road climbs sang to me — I was already hooked on riding up any and every mountain I could, and learning that there were climbs much longer and higher than anything here in Australia had me dreaming of the possibilities.

The day my copy arrived I sat down and went through it forensically, dog-earing a whole host of pages to highlight the climbs I fancied tackling. Chief among them was Mt. Evans.

Forty-three kilometres long, nearly 2,000m of altitude gain, a summit that poked above 4,300m, the highest paved road in North America — this climb had captured my imagination. If I could only conquer one US climb in my lifetime, I decided, this would be it.

Earlier this month, nearly a decade after first concocting a plan to tackle Mt. Evans, I finally got the chance to do so. I was underprepared, I hadn’t acclimatised, and I had no idea what to expect. What followed was one of the most memorable days I’ve ever had on the bike.

I notice the altitude almost immediately, barely a kilometre after clipping in and setting off. It’s not debilitating by any means, but for the minimal effort I’m putting in, I’m breathing noticeably faster than I normally would. It’s hard not to feel like things are about to get a whole lot worse.

I tell myself to relax, to focus not on what’s coming but on how I feel right now. But it’s not easy. The ride’s only just begun and already I’m at the highest altitude I’ve ever been on a bike. Oh, and there’s 42km of climbing still to go.

I’m at roughly 2,300m above sea level, having just left the tiny town of Idaho Springs, Colorado. My destination: the summit of Mt. Evans where, at a breathtaking 4,300m above sea level, the air contains roughly 40% less oxygen than it does in my sea-level hometown of Melbourne.

A few kilometres into the climb.

As I try to settle into a rhythm, I can’t help feeling that the odds are stacked against me. I’m on a borrowed bike that I’m riding for the first time. I haven’t ridden at all in weeks, and I haven’t climbed a proper mountain in the past 12 months, let alone something that’s 2,000 vertical metres from bottom to top and more than 4,000m at its summit. And speaking of altitude, I’ve barely acclimatised at all.

In short, my preparation hasn’t been ideal. In fact, I’m expecting to fail and I’m ok with that. At least that’s what I keep telling myself …

To be honest, the distance, the volume of climbing, and my lack of recent form don’t worry me too much. I know that stubbornness and pride will allow me to overcome all of those obstacles. It’s the altitude that’s got me worried. And with good reason.


Back in March 2013, a month after I started at CyclingTips, site founder Wade Wallace and I visited an altitude training centre in Melbourne’s south east to see what riding at altitude was all about. In a room set to simulate 3,000m of elevation, Wade and I began an introductory session to see how our bodies coped with less oxygen than normal.

Every few minutes we were instructed to ride a little bit harder and all the while our instructor monitored the amount of oxygen circulating in our blood (via a pulse oximeter). I distinctly remember the feeling of disappointment when, partway through the session, the instructor asked me to stop pedalling.

I felt completely fine but, as the instructor explained, my oxygen saturation had dropped below 75% — low enough that it wasn’t advisable to continue. Wade, meanwhile, pedalled happily on.

The instructor explained that some people just aren’t suited to high-altitude. Just as those who are born and raised high in the mountains thrive at such heights, so us lowlanders have a tendency to struggle when the air gets thin. My Dutch blood probably wasn’t doing me any favours, either.

My test was cut short (left) while wade was able to continue on (right).


Ever since that day at the altitude training centre, I’ve had it in my head that high altitudes and I will never really get along. My concerns were only amplified when I told my Colorado-based colleagues of my plans to tackle Mt. Evans during a recent visit.

“Things get ugly up there, even for us,” said CT’s editor-in-chief Caley Fretz by way of warning. Tech editor James Huang had me even more concerned, sending me an image of oxygen canisters available for sale online, with the caption “I’ll order a case of these for you.”

So as I set off on my ride from Idaho Springs, I do so with a knot of uncertainty in my stomach. I have no idea what it’s going to feel like riding at above 3,000m, let alone 4,000m. I have no idea whether I’ll be able to handle it.

The smooth tarmac of Highway 103 winds beautifully into the Arapaho National Forest, gently gaining altitude at a very consistent gradient of 4-5%. There’s a reasonably stiff breeze blowing down the road, but the serpentine nature of the ascent means that any headwind soon becomes a tailwind, like a divine hand pushing me gently up the mountain.

I’m feeling good; much better than expected. I’ve chosen a tempo that’s even easier than I think I need. I want to save as much energy as I possibly can, for when things “get ugly”. I’ve got more food with me than I’ll probably eat, and more water than I’ll probably drink. In this sense, at least, I’m prepared.

The miles are ticking away with relative ease, and I haven’t even needed to resort to podcasts to distract me from the challenge. I’m simply able to spin away, enjoying the ever-changing scenery, the perfect summer weather, and the experience of climbing a mountain I’ve dreamt of riding for so long.

I’ve got my Garmin in my jersey pocket so I’m not really paying attention to how far I’ve ridden. It’s partially by necessity (I’ve got no Garmin mount with me) and partially by design: I’d rather focus on the experience than how much of this monstrous climb I’ve got left to do.

And then, out of nowhere, I round a left-hander and Echo Lake is there on my right, all blue and glorious in the summer sunshine. It’s a welcome sight not just for its eye-catching beauty, but for the fact it marks what is essentially the halfway point of the climb.

A few hundred metres up the road I stop at a visitors’ centre to buy some more water and drop the bike’s saddle by a few millimetres. It is my first ride on it, after all. I’m at around 3,000m here and a brief rest is more than welcome before I make the right turn onto Mt. Evans Road for the second half of this massive climb.

Looking out over Echo Lake.

So far, the altitude has given me far less grief than I’d expected. I can still feel it — it’s lingering in the background, silently, invisibly, making it just that little bit harder to get in a deep breath. But I suspect the gentle tempo I’m riding is masking the true difficulty such heights can pose. I shudder to think what it would be like to ride at any sort of intensity up this climb, let alone race it.

At around 3,200m above sea level, things take a turn for the worse. For the first time I’m struggling to breathe properly and even though the gradient is barely above 4%, I’m in the 32-tooth cog and still finding it difficult. This isn’t good — I’ve still got 20km of climbing to go, and more than a vertical kilometre between myself and the summit.

I try to compose myself, and eventually decide to listen to a podcast to distract me from the difficulty. It works — before too long I’m back in a comfortable rhythm and feeling like I’m on top of things once more.

It occurs to me later that eating is the culprit. The effort of wolfing down a banana or energy bar means I’m not properly able to breathe through my mouth for a few moments, which sends me into mild oxygen debt. Each time it takes me a few minutes to get back into a comfortable rhythm.

At about 3,300m I round a right-hand bend and suddenly I’m above the treeline and entering the moonscape that I’ll become so familiar with over the next hour or so. It’s a landscape that reminds me of Mt. Hotham back in my home state of Victoria, both for its beautiful desolation, and for the remarkable views available from the roadside.

By now I’m also starting to catch my first glimpses of the Meyer-Womble Observatory at the summit of Mt. Evans, which spurs a realisation: I’m going to make it. No matter how hard things get from here, I’m close enough and with enough in reserve that I’ll be able to make it through. Any remaining uncertainty evaporates and I find myself enjoying every pedal stroke.

The final section of the Mt. Evans climb is a series of seemingly never-ending switchbacks through a mostly barren boulder field. In an article for Peloton Magazine back in 2011 Jered Gruber wrote that even at 5% these high-altitude hairpins feel more like you’re riding at 15%, such is the challenge of the thin air. It doesn’t feel that hard to me just yet, but I suspect Jered was riding a little harder than I am.

As I reach the final bends to the summit, poking through the 4,000m barrier, the wind whips up significantly. It’s blowing hard in my face, slowing me to little more than a crawl.

But even into this blustery headwind — the strongest I’ve felt in a long time — there’s nothing that can sour my mood. The summit is almost within reach and I know now that nothing can stop me. And besides, by the time I pass through the next switchback, the wind will be at my back.

There’s a long procession of motor traffic in the final metres to the summit and I overtake a handful of vehicles as I reach the carpark at the top. I’ve made it, and I couldn’t be more thrilled.

I feel the altitude as soon as I step off the bike. I haven’t pushed hard at all, but as I unclip and stand upright I instantly feel woozy and unsteady on my feet. I grab hold of a nearby signpost to ensure I don’t topple over.

Soon enough I’m feeling fine and I’m able to enjoy the view and snag some photos to commemorate the achievement. Judging by the thick coats and beanies everyone else is wearing it must be cold up here. Not that I can feel it — I’m still warm from the effort and from the satisfaction of completing a long-held goal. A goal that, just a few hours earlier, I thought was likely beyond me.

Coming into this ride, I’d anticipated several hours of tight-chested suffering, multiple stops to catch my breath, and the very real possibility of failure. But, to my great surprise, the thin air had less of an effect than I’d expected.

The gradient of Mt. Evans certainly helped. Rarely did the gradient spike beyond 5% and at no point did it reach double figures. I suspect my experience would have been considerably different on Pikes Peak, another of Colorado’s 53 “Fourteeners” — mountains that peak above 14,000 feet (4,267m). With 2,360m of altitude gain over 38km — including a long section at roughly 10% — that climb is certainly harder than Mt. Evans, making a measured effort far more difficult.

Climbing Mt. Evans would also have been much harder had I ridden at anything more than the pedestrian tempo I did. As it was, I was content to spend 3.5 hours climbing 43km, making Mt. Evans far more doable than I’d expected … even on an unfamiliar bike, without acclimatisation, and as a lowlander who’s genetically predisposed to struggling at altitude.

Tips for climbing at altitude

If you haven’t already, check out the video from my ride up Mt. Evans at YouTube.

Looking to tackle a super-high climb like Mt. Evans? Here are some tips you might find useful:
1. Pace yourself. Ride at a gentler tempo than you think you need to. Save as much energy as you can for when the altitude really kicks in.
2. Be prepared for your power output to be lower than normal. You’re getting less oxygen in, which means you’ll have to work a lot harder to produce a given power. Don’t panic.
3. Avoid going “into the red”. The altitude will mean you pay for any efforts above threshold. Recovery will take a lot longer than you’re used to.
4. If you do get caught out by the altitude, take a moment to compose yourself. Focus on slowing your breathing. Breathe in for five seconds, hold your breath for five seconds, then breathe out for five seconds. You can do this either on the bike or when you’re stopped. It should allow a little bit more oxygen to cross into your bloodstream. (Thanks to Andy van Bergen for this tip!)
5. Respect the mountains. Weather conditions can change rapidly and dramatically in the high mountains. Bring clothing for all conditions, and be prepared to get out of there if a storm brews up. You don’t want to be on top of a mountain, above the treeline, when lightning starts.

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