Ken Roberts - - Ski Backcountry

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weight on feet versus weight in pack

10may

key points

  • main issue is relative increase of weight during ski-climbing compared to weight during summer-walking, for on the feet versus in the pack

  • bottlenecks in performance

  • this can be interpreted as a training problem -- if the weight on feet in summer-walking is increased

  • second issue is that in breaking trail in soft snow the motion is different than summer-walking.

  • another possibility is to use arm muscles to help left weight on the skis up and forward

implications

weight on feet is (relative to weight in pack) less important for:

  • skiers who tour lots of days (because their specific muscles get developed to handle the extra weight).

  • skiers who do serious pre-season specific training.

  • skiing in more popular areas, where often there is a climbing track already in place.

  • skiers who mostly get directly into the steep climbing, without long gentle approach.

Less important because stride-length is shorter, so quick acceleration of ski forward is not so critical. Relatively less important because the other main leg-extension muscles for pushing overall body-weight up the hill are getting taken closer to their limit on each stride.

  • skiers who care a lot about downhill skiing performance (perhaps because they ski a lot in more difficult snow conditions: crud, crust, already-tracked. Or perhaps because they get assistance from lifts for lots of their ski touring).

  • skiers who carry heavy packs.

weight on feet is (relative to weight in pack) more important for:

  • skiers who tour mainly in one or two holiday weeks, or only once a week.

  • skiers who do lots of trail-breaking in soft snow -- either because they're in less trafficked areas, or because they like getting out there quick after the new snow falls.

Important because breaking trail requires lifting the ski and weight on feet much higher than in summer-walking, a problem because: (a) the other muscle groups can't help as much, because from of raising-mass-up-the-hill perspective, it's mostly wasted; (b) normal specific-muscle training from normal summer-walking doesn't help much; (c) it's not so easy to perform special summer training to help with this different lifting motion.

  • skiers who do long gentle approaches

Important because weight in pack is relatively less important because it's not being lifted up a hill. And because skiing on the flat uses longer strides, so the amount of time needed to bring the ski forward farther becomes a key performance driver. So accelerating the mass on the feet quickly becomes key, so the peak-force load on the specific muscles is greater.

  • skiers who climb fast.

because climbing fast requires moving the ski forward quickly, which means accelerating the mass on the feet quickly, so the peak-force load on the specific muscles is greater.

Interesting that some of these implications tend to correlate with "skiing in the European Alps". And that some ski bindings which are not as light-weight seem to be popular in Europe.

bottlenecks on performance

kinds of "bottlenecks":

  • peak-force load on specific muscles and joints

tends not to be important for "normal" climbing on skins -- but can be very important for fatigue in "technical" situations.

  • aerobic capacity of specific muscles

very important for ski touring. very trainable.

  • anaerobic-handling capability of specific muscles

Should matter only for racers, because ski tours normally go on for several hours. But sometimes inexperienced skiers let themselves push a little too hard and get into anaerobic mode on a tour. Oddly, it seems that getting partly into anaerobic mode in training sessions is often very helpful in developing aerobic capacity.

  • fuel distribution

Becomes a limiting factor for longer single-day tours, as locally-stored glycogen gets depleted. Also for multi-day tours. Tends to be developed by long-distance sessions which are also beneficial for developing specific-muscle aerobic capacity.

  • total aerobic capacity of body

VO2max is not directly important for ski touring, because ski tours go on for several hours. Doing lots of ski touring, and specific training to increase ski touring performance tends can have a positive impact on VO2max (for people whose VO2max is not already high from other activities). And people who have a high VO2max for other reasons can often leverage that to more rapidly develop specific-muscle capabilities needed for ski touring.

  • total anaerobic-handling capability of body

If relevant for any skiers going uphill ... only for racers, and mainly for special "sprinting" situations.

 

 

 

Bryce Canyon, Utah

10jan

Sharon and I drove down to Bryce over the weekend and had a great time. Not enough snow left for skiing down inside the main amphitheater area around Sunrise Point and Bryce Point, so we went hiking on the snow-covered trails thru the red rocks and green trees -- down and up from Bryce Point and around the Peekaboo loop.

I had skied in from Bryce Point years ago, but hiking on the trails with snow was even better. Those trails are very well designed for going thru amazing rock formations -- took me places I had never thought of going on skis. With snow, a good candidate for top 10 best hiking trails in the world.

Being down inside gave me a good look at the steep-ish shots off the rim -- and confirmed my memory that they're pretty short.

My advice from two days of hiking and two days of skiing: Come to the Bryce main "amphitheater" area for the winter hiking, rather than the skiing.

rules and advice from the Park

update 10feb16: I received an email from the Park's chief ranger saying that the actual regulation is:

"The slope between the Plateau Rim and 7600 foot contour elevation is closed to skiing, snowboarding, sledding or sliding devices."

( This page on the National Park website gives more explanation.)

from the paper they gave us when we paid our $25 per car fee at the park entrance, from The Hoodoo
Bryce Canyon Map & Hiking Guide, Fall-Winter-Spring 2009-2010
quote from page 4:

"Where can I ski / snowshoe?

Snow depth at Bryce can be variable, so it’s important to make back-up plans. With 3-4 feet of snow the entire park is skiable. The only area that is always “Out-of-Bounds” is skiing off the rim. If you want to slalom through hoodoos, you will have to go to Red Canyon. When snow depth is less than 1 foot, the only skiable surfaces are the groomed trails at Ruby’s Inn, the Red Canyon Bike path and the Fairlyland and Paria roads.

Unlike skiers, snowshoers are allowed to follow the hiking trails below the rim. When snow depth is less than 1 foot, the awkwardness of snowshoes outweighs any “flotation” advantage. On the popular trails where the snow quickly becomes packed and icy, hiking boots with traction devices are often more helpful than snowshoes.

Ski and snowshoe equipment can be rented at Ruby’s Inn. Traction devices for hiking boots can be purchased at the Visitor Center or Ruby’s Inn.

Avalanche Safety

Although uncommon, Bryce avalanches can take the lethal form of mixed snow and mud."

. . . [ etc ] . . .  

GPS

To help follow trails that might be buried under snow . . .

These are raw .gpx files recorded by our GPS while hiking that day -- probably some significant inaccuracies -- not a substitute for intelligent attempts to follow the trail from terrain features.

Cedar Breaks, Utah

We explored around the north half of the canyon -- saw that the areas with lots of red rock did not have any continuous skiable lines with the early-season snowpack - (though one obvious spot at first looked inviting from its top).

So we explored along the rim in the areas with more trees. Sharon would wait while I went down a little looking for an entrance to lower into the canyon, then I'd climb back up and say "not enough snow yet". Seemed like everywhere I looked there was a band of like 100 vertical feet around 40 degrees thru a slot in the cliffs -- with some rocks showing, or green ice in a gully.
Finally after Sharon went back to the car, I found a way that would go, but the snow was funky and it was late in the day, so I decided not to take it.

From the topo map, looks like could be something like 1800 vertical feet from the rim down to the bottom (way more than any place in Bryce Canyon N.P.) -- though I sorta doubt there's anything like that much continuous quality skiing.

I know a couple of skiers who've skied to the bottom thru one of the more treed sections, and they said that was on their second time there -- first day they explored around. So I guess that's the normal pattern for Cedar Breaks --
go there first for the fun of exploring.

It was pleasant and pretty with gentle ups + downs thru widely-spaced trees along the rim -- on a blue-sky day in six inches of new powder looking across to red rocks in the sun. Too bad there wasn't a good base under the six inches -- but anyway a fun day on skis. 

more . . .

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