Nutrition for an Alaska Ski Mountaineering 1 Day Push

ski mountaineering

This article was first published in May 2015


By Rob Shaul

One of my sponsored athletes, Jessica Baker, is planning for a May ski mountaineering attempt of University Peak in Alaska’s Wrangell-St. Elias Range. Jessica is sponsored by Outdoor Research and Dynastar, among others, and is an Exum Guide, backcountry ski guide, and ski instructor trainer at the Jackson Hole Mountain resort, Alaska Heli-ski guide, and former world tour freeski champion. She and two other women will be making the climb.


Fitness Demands

The vertical summit of University Peak is 14,470 feet, and Jessica’s team’s base camp will be located at 3,000 feet. She’s looking at an 11,100 foot elevation gain from base camp to summit, in one 24-30 hour push.

For the purposes of this plan, I used a 27-hour camp to camp effort and assumed two hours to ski down – so 25 hours total of uphill movement.

According to Jessica, just 1,400 feet of the climb will be done skinning. Her team will boot packing and ice/snow/mix climbing the remainder 9,600 feet to the summit.

The climbing is considered class II and III ice and ridge climbing – so the team will be using one or two ice tools and wearing crampons on the way up. It’s mostly straight up.

I had Jessica load her pack – gear, water (2 liters), skis, skins etc., and weigh it. Her pack weight was 40 pounds. 

Here are the final fitness demands:

  • 25 Hours of Uphill, Snow Mountaineering
  • 2 hours of downhill skiing
  • 40# Pack, 11,100 feet of vertical gain
  • 27 hours total

Pace: 11,100 feet divided by 25 hours means Jessica and her team will need to climb 440 feet per hour to stay on schedule. This is an easy pace doing step ups or climbing up a nice boot pack, but in unpacked snow and unknown conditions, this could be a challenging pace. Also, as you’ll see below, every 4 hours, the team will need to stop for 20 minutes to melt water. So they’ll lose just over 2 hours of climbing time to snow melting. Thus, their actual climbing pace will be 11,100 feet divided by 23 hours or 482 feet/hour.


Caloric Demands

Jessica weighs 130#, but coupled with a 40# Pack, will need top propel 170# uphill, total. When calculating her calorie burn rate, I, therefore, assumed she was a 170# person.

A 170# person, running on flat ground at 10 minute/miles, will burn around 700 minutes/mile.

Jess headed up the bootpack at Snow King...again.
Jess headed up the bootpack at Snow King…again.

The snow, incline, and use of ice tools on University Peak (upper body workload) make a huge difference for Jessica and her team. A 170# person, doing uphill snow mountaineering, will burn 900-1,200 calories per hour. Pace matters, so for the purposes of this project, I assumed Jessica and her team will burn 1,000 calories per hour during their summit push. This is 25,000 calories over 25 hours!

The first thing to understand is there is no way the team will be able to replenish enough to meet this demand. The best they can do is stem depletion.

Carbohydrates – sugar – will dominate their refueling effort. Sugar is the energy source the body can absorb most rapidly, the most which can be absorbed is 1 – 1.5 grams/hour – or 250-350 calories an hour.

→ Hydration
Jessica and her team will need to do their best to control water loss, especially sweating, through layering as they climb. Staying hydrated is key to their overall performance and, combined with electrolytes and salt, to stem off cramping.

On average, people sweat .8 – 1.4 liters per hour during exercise. For the purposes of this plan, I’m assuming Jessica will sweat 1 liter/hour. Which works out well, because, the most fluids, on average, a person can absorb in an hour is .5 liters.

Water alone won’t ward off cramping. Jessica will need to supplement her water with salt and electrolytes – through an energy drink mix and electrolyte tablets.

→ Water
Unlike an ultra marathon, there will be no aid stations along the way. Jessica’s team will need to carry food up the mountain and stop to make water at certain intervals.

I’m recommending they start with two liters of water and stop to make water and eat solid food every 4 hours (6 total stops).  Ideally, they will work to limit these stops to 20 minutes.

→ Nutrition Plan
I want Jessica to consume 350 calories/hour during this summit push using a sports drink mix in her water and energy gels.

→ Energy Drink
Specifically, I recommend Jessica use either Hammer Energy Perpeteum or GU Roctane Energy Drink mix for her sports drink and mix 2 servings in each of her 1-liter water bottles.

GU Roctane Mix has 250 calories, all carbs, per serving.

Hammer Energy Perpeteum has 270 calories and includes 20 calories from fat, plus 7 grams of protein per serving.

I want Jessica to drink .5 Liters of the drink per hour, or 1 liter every two hours. Using an energy drink will allow her to stay hydrated and also “drink” calories.

There are two additional reasons I want Jessica to get the majority of her carbs from an energy drink. First, is weight. Each energy drink serving is 250-270 calories and 2.5 ounces. Jessica would need to carry 2.5 gels to get the equivalent calories – or 3.75 ounces. As you’ll see below, for the trip she’ll need 25x energy drink servings or 62.5 oz. Gels for the same amount of calories would weigh 93.75 ounces. In other words, using the energy drink servings saves Jessica almost two pounds in her pack.

Second, she’d have to consume 3.5 gels per hour ….. and this would be time-consuming, and simply difficult. Drinking calories is the way to go.

→ Gels
In addition to .5 liters of energy drink, I want Jessica to consume one energy gel each hour – on the bottom of the hour. I’ll recommend GU Roctane (100 calories) or Hammer Gel (90 calories) or a mix of the two.

→ Solid Food
Every 4 hours, Jessica and her team will need to stop to melt snow for water. This will be an opportunity to consume some solid food. Again, this food needs to be carb-dominant – 75-80% carbs, the rest protein. Easiest will be a protein bar or half a sandwich. Early on in the climb, this solid food will help with performance and morale, but later in the climb, could lead to stomach issues.

Note here I don’t prescribe any fat – like sausage or cheese. Jessica will use fat to fuel her climb, but it will come from fat stores already in her body. Any fat she consumes during her climb won’t make be digested in time to use for energy.

→ Caffeine
Many gels include caffeine – which can help performance and alertness. I’ll recommend Jessica avoid caffeine early in the climb, but begin to consume gels with caffeine half way up. I’ll also recommend she take along a small bag of chocolate covered espresso beans if she needs to pump alertness at the most technical climbing near the summit, and before the ski down.

→ Electrolytes
Energy drinks contain electrolytes, but I can’t rely on them to ward Jessica off from cramping. I’m recommending she supplement with 2x electrolyte tablets per hour.

→ Food Weight

Finally, food weight is an issue. Here’s the break down:

25x Gels (1 per hour) @ 1.5 oz/each ……………………………….. 37.5 oz

25x Energy Drink Servings (1 per hour) @ 2.5 oz each ………. 62.5 oz

6x Protein Bars (Hammer Whey Recovery) @ 2.65 oz/bar ……16.9 oz

Expresso Beans ………………………………………………………………..8.0 oz

2 Liters Water 35 oz/per liter ……………………………………………..70.0 oz

Total                                                                        195 oz or 12 pounds!

So, approximately 8 pounds of foot and 4 pounds of water at the start of the climb. As she consumes the food, the pack with lighten …..



I designed a sport-specific training plan for Jessica’s University Peak climb, and as you imagine, it’s dominated by step up and uphill boot packing. The plan includes long “mini-events” – and I’ve encouraged Jessica to test energy drinks and gels during these events. Everyone is different, and some products and flavors do better with some stomachs than others. Ideally, the “mini-events” will help Jessica discover which products work best for her.




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