One question we often get is: How fit do I need to be to climb/run/ski Everest or Denali or Rainier…or…? Our collective 100-plus-year history of endurance training and mountaineering clearly points to the conclusion that you can never have too much aerobic fitness. And when I prepare for an expedition to an 8,000-meter peak, I know my training is going to require a lot of the following three things: duration, consistency, and elevation. Beyond the training for my own (many) expeditions, Uphill Athlete has now coached dozens of successful 8,000-meter-peak climbers. We feel that we can confidently predict an athlete’s physical preparedness using those same three metrics.

We use TrainingPeaks and find it to be essential in our training and coaching practice. Training without monitoring can easily revert to random exercise. (Uphill Athlete is a paying client of TrainingPeaks; we receive no kickbacks or sponsorship of any kind.) Their “Dashboard” feature, in conjunction with the assignment of a Training Stress Score (TSS) for each workout, is the basis of this and many other analyses we make of our athletes’ training on a daily, weekly, and annual basis. If you’re not using it to measure and plan your training, we highly recommend you try it.


By duration I mean weekly training time intelligently distributed by a good training plan or coach. For the sake of this post, I’ll speak in terms of generalities, and below you can see a chart that calculates an athlete’s average weekly training time for the six months leading up to an Everest climb. This climber averaged 8.5 hours per week over six months. (Note that there are a few weeks where nothing was recorded because she went to Aconcagua.)

Eight and half hours per week is only an average. It takes time to get to the fitness level whereby one can sustain a training load of 15-plus hours per week. Not to mention the time needed for the logistics of driving to and from trailheads, eating, prepping, showering, etc. The only way to rack up this kind of training volume is with consistency.
Weekly training volume for six months leading up to Everest
Weekly training volume for six months leading up to Everest. This climber’s six-month average was 8.5 hours per week.
Performance Management Chart
A Performance Management Chart taken from an Everest-bound athlete’s TrainingPeaks account from October 1, 2016, to June 1, 2017.


Think of the blue line, which TrainingPeaks calls CTL, or Chronic Training Load, as fitness. We’re not machines, and this is not an exact science, so CTL isn’t perfect. But it is a very useful representation. So how fit do you need to be? In terms of CTL: Denali 75 | Everest 100 | Everest without supplemental oxygen 125.
To climb Denali you want to have a CTL of 75 for two months. For Everest at least 100 for three months. For Everest without supplemental oxygen, we suggest a CTL of 125+ for three months. These are rough guides we’ve worked out over the last five years and they do seem to be pretty good indicators of physical preparedness.
To get your CTL up that high, a couple things need to happen. First off, it is well understood over a wide variety of sports that the maximum rate you can increase an athlete’s CTL safely is 3–5 points per week. So to get to a CTL of 50 takes a minimum of 10 weeks. And that’s in a healthy, usually young, adult. To get to 100 you need 20–30 weeks in total. You can also work backwards. To get from 30 to 100, an increase of 70 CTL points, you need 15–23 weeks. AND THEN you need to hold that CTL there for a month or more. So to get to a CTL score of 100, you need roughly five months to get there and then one to four months to hold the training load that high (while staying healthy). This requires consistency over time.
Take our example Everest-bound climber, a person with a long training history, whose chart I posted above. Her CTL broke 100 on 2/20/17, peaked at 137 on 3/28/17, and stayed above 100 until 5/1/17, when the climb began in earnest.
This example illustrates the need for consistency and is why you need six to eight months to become fit enough to be prepped for an ascent of Everest with supplemental oxygen. Of course if you have more time, then so much the better. But do keep in mind that once your CTL is up around 100, you’re training 15–24 hours a week to keep it there, so this takes a big chunk of time.


At some point, to have you mountain-ready, you have to be going uphill for thousands of feet each week. Climbing requires different muscles than running flat/rolling terrain. Your glutes, hamstrings, and the musculature around your pelvis are all utilized in different ways when you’re going uphill. Whether you do this outdoors, in stairwells, or on a treadmill, vertical gain is crucial.
Average vertical gain by month
Average vertical gain by month leading up to Everest.
Despite the missing weeks in January due to her climb of Aconcagua, and without correcting for that, the example athlete’s average weekly vertical was 4,700 feet over six months, with weeks as high as 17,000 vertical feet.

Getting Fit to Climb Everest

In summary, if you want to climb an 8,000-meter peak, you should:
  • Start training ASAP. Note that it takes most professional endurance athletes 10 years of structured training to approach their genetic limits of aerobic fitness.
  • Plan to ramp up from around 7 hours of training time a week to over 20 hours per week.
  • Plan to put in a lot of vertical.

-by Steve House, Uphill Athlete co-founder

You May Also Be Interested In:

24 Week Mountaineering Plan
24-Week Expeditionary Mountaineering Training Plan: Our most complete, best-selling mountaineering training plan
My Everest, Photo: Cory Richards
My Everest: A personal account of training for and climbing Everest without supplemental oxygen, by Uphill Athlete Cory Richards

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