Ken Roberts - - Ski Backcountry
Gi and I had a great four days of ski touring over the first weekend of May, then afterward I had a great day with Andreas on the Piz Bernina.
Below more details on each.
Since my airline ticket was to fly home from Geneva, afterward I drove west across Italy, and along the way was lucky to get good weather for a ski tour on Gran Paradiso (4061m) -- highest mountain whose base is completely within Italy [ photos ].
Gi and I had a great three days of touring and skiing in the Glarner Alps over the first weekend of May.
The Glarner mountain group is southeast of Zurich, sort of between Andermatt, Altdorf, Glarus, and Chur.
My feeling was that the area was spectacular with dramatic peaks and big glackers like the Berner Oberland, but without the 4000m peaks.
summary of our route
We started by meeting in the parking lot at the base of the Disentis lifts early in the morning looking at an unclear weather forecast and talking about several single-day alternatives nearer and farther, one- or two- or three-day versions of the Glarner Alps tour. Then a couple of hours of lift-served skiing in 30cm of fresh powder, then from the top of the lifts climbed the Oberalpstock which turned out to be a fine ski peak. Then a long mostly gentle descent east followed by a long climb north in the Val Gronda da Cavrein. A tricky crossing onto the Hüfi snowfield, more climbing, and were glad to arrive at the Planura hut after a long day.
Next day Gi skied the Gross Schärhorn from the summit (possible because of so much snow in the last few weeks) and then after a long gentle traverse along the snowfield we both skied Clariden from the summit, and slept another night at the Planura hut.
Third day we first skied across the Sandpass and further down south, then climbed long northeast and crossed a couple of ridges to join the main ski route and continued to the summit of Tödi, highest peak in the Glarner Alps. Then we made our descent directly south, which turned out to be very interesting, then that joined the main Val Russein descent route down to the Disentis road.
more details . . .
Disentis lifts - Oberalpstock - traverse Val Gronda to Planura hut
Gi had heard that the Disentis ski lifts might start early for a single ride up for ski tourers to get an early start, but there was no evidence of that. Seemed to me the lifts and trails had been closed for three days since the previous Sunday, and meanwhile there had been about 25 cm of new snow. So before they could open the upper lifts they needed to some avalanche control and additional grooming. Fortunately they allowed us to ski some extra runs while waiting for the top T-bar lift to open, and we did our part to put some tracks into the 25 cm of fresh snow. At least the T-bar.opened to pull us to the top around 10:30 -- much later than we had expected.
From top of the Disentis lifts we climbed on skis first around south side of Piz Ault, crossing some steep-ish SE-facing slopes. Then about 10 meters steep on foot carrying skis cross East ridge of Piz Ault. We crossed near the east end of the main ridge, before it dropped much lower still further east. Underneath the snow we were glad to discover some steep rungs, and rope to grab at the top. North side of the ridge was steep-ish. Gi traversed west a short ways then down a slope at least 40 degrees between some rocks. I stayed high traversing further north across a 35 degree slope with steeper rocks below, then skied down a 25-30 degree slope.
Oberalpstock (3328m) -- a rather nice ski peak. With the big snow in April, we were able to climb all the way to the summit on skis. Another party coming from the east had set a track to about two-thirds, but then gave up and skied down, then over a pass west and then south to Sedrun. Gi continued upward, then allowed me the honor of finishing breaking trail to the summit. Fun skiing down in 25cm of fresh snow.
Going east on the snowfield was nearly flat, so we did lots of poling until we reached the . . .
Chamanna da Cavardiras hut (around 2600m) -- unwardened on this day, but we heard that two ski touring parties had slept there to break up the distance between the Oberalpstock and the Planura hut. (something I would consider doing if I tried this tour again).
The slope east down toward Val Russein had a moderate grade, but the snow had warmed up by the time we reached it (partly due to the late opening of the Disentis lifts that day), so our descent eastward was much slower and much more work than we expected. At around 1800m . . .
We turned and climbed North up the Val Gronda da Cavrein. Our other option would have been to ski out south down the Val Russein to our other car. We assessed the avalanche risk, and it looked like everything steep had already slid already a day or two before, and slopes of similar aspect and steepness had not slid so far on this day. So we climbed the Val Gronda, and Gi masterfully set an excellent track up through the steeper sections. But then at the top . . .
tricky pass crossing around 2840m from north end of Val Gronda da Cavrein and the Hüfi firn. At the west end of the pass, we down-climbed a short snow-covered section at least 50 degrees.
Our edition of the Klausenpass 1:50000 ski route map showed this crossing as skiable, but that seemed very unlikely, and we were there in a big snow year. Gi suggested that the glacier has receded significantly since the map was last edited. Looking back we both thought maybe there was a slightly less steep way down about 30 meters east from the west end of pass -- but that was a big snow year. If I do this tour again, I would come prepared for a 20 meter abseil / rappel. (? Not sure if this pass could have been climbed upward (north to south) with such loose snow lying over rock without many good holds ?)
Hüfi firn (glacier) from top of Val Gronda da Cavrein to Planura hut trickier to navigate than we expected. Required a climb, a descent, then another climb. Would not want to try it in bad visibility.
Planura hut (2950m) -- I liked its distinctive architecture and perch on the rock. Even though we arrived after dinner, the warden soon warmed up some food for us. There were only about six guests our first night (on Labor Day!). But on our second night there on the four-day holiday weekend it was packed full, and we were assigned to sleep in the winter room.
I heard that when the popular Fridolins hut is all booked, skiers going for Tödi instead use the Planura hut. Also, with the new lift from the north side by the east side of the Klausenpass, many skiers climb over the top of the Gemsfairenstock (2972m) then stop at the Planura hut for the snack and the view (perhaps also climbing and skiing Clariden along the way), then descend to the Fridolins hut where they have reservations.
I think the alternate route from the Planura hut to Tödi we did by way of Sandpass and Val Russein on the SW side of Tödi is more interesting and less crevassed than the normal route around the E side by way of Fridolins -- but the normal route is also easier. Anyway the normal route could be reached after sleeping at Planura by skiing east down to the Fridolins hut first thing in the morning.
Next time: (a) I would consider sleeping at the (unwardened?) Cavardiras hut the first night, because then less need to depend on early opening of the upper ski lifts of Disentis, and plenty of time to enjoy skiing the Oberalpstock. (b) learn more about the tricky pass crossing, and bring equipment for abseil / rappel.
Total for the day: 10 hours from top of Disentis T-bar to Planura hut, +2200m climbing and 21km distance -- including up and down the Oberalpstock.
Gross Schärhorn + Clariden
Next day we decided not to go for Tödi yet, and instead enjoy some interesting peaks around the Planura hut. Turned out the visibility was bad most of the morning, so Tödi wouldn't have worked anyway.
Gross Schärhorn (3295m) -- Gi skied it (in low visibility) from the summit, likely not possible in most years. I decided it wouldn't be fun, and I needed some rest from yesterday, so I stopped around 3000m. We had skied down into the Huegi firn to reach the Schärhorn, then we went nearly flat along its north edge around to the east side of Clariden. Lots of flat slogging, but in such a pretty place.
Clariden (3267m) -- the popular east slope was not real steep, straightforward climbing, on snow all the way to the summit. Snow not so great on descent, so we cut it short, took a shortcut south to descend more toward Planura, avoid some more flat slogging.
Tödi + descent of Val Russein
Tödi (3614m) -- highest peak in Glarner Alps and the highest peak near Zürich. The normal ski route is from the northeast by way of Fridolins hut and around the east side.
Perfect weather day, we did an interesting alternate route of ascent, and a different alternate route on descent.
We started from Planura hut, south over the Sandpass and down toward Val Russein.
Seemed to me like south side of Sandpass was around 35 degrees (or more?) for like 100 vertical meters. Fortunately the snow was a bit like "packed powder" on a groomed ski trail -- firm but grippy.
If it had been frozen corn snow or wind-pack I might have down-climbed it on crampons.
Then down a moderate slope for a ways (we did the easterly descent route), but then seemed like around 30 degrees on frozen corn snow in the early morning for at least 200 vertical meters, with what looked rocky knoll near the bottom of the slope. The possibility of a long slide crossed my mind, so I tried to ski on the half of the slope that seemed like it was not directly above the rocky knoll.
Those with less confidence in their hardpack skiing techniques might consider going down that section on crampons.
We stopped our descent around 2000m, then climbed northeast up a long SW-facing slope. One guidebook says the average is around 27 degrees with some steeper sections. Seemed to me the first lower section was at least 30 degrees for like 300 vertical meters or so. It was frozen corn snow early in the morning, so I climbed it on skis with cutters (harscheisen).
Not the place to be on skis unless you can do steep kick-turns in your sleep. Not the place to discover that you do not already have expert technique for steep kick-turns. If not sure, do it on foot with crampons.
Another steeper section near the top. We climbed it all the way on skis with a good track already set in semi-fresh snow. One person booted the last 40 vertical meters.
I'd guess that once that nice up-track got trashed later in the day by descending skiers, so in future days most skiers would need to boot it, and in unfavorable snow conditions, crampons could be necessary.
Just over the top of that ridge is a sunny brunch spot. Then a steepening climb into a narrower spot under a big rock -- much 30-35 degrees, then a non-long section at 40 degrees. Most skiers booted up the steep section, but Gi climbed it on skis (in favorable snow conditions -- fresh snow in the shadow of the big rock).
Crossed another ridge on snow, down a little, then climbed moderately to join the normal ski route coming from the east side, and continued moderately to the summit (with lots of other skiers on that holiday weekend).
Fresh snow 25-30 cm south off the summit (we selected a steeper line), then moderate thru some crevasses. South-facing untransformed snow not so great, so we climbed on skins to the second ridge of our descent route, then skied down thru the narrower 40 degree section. Fortunately we were the first two descenders, so there was some decent fresh powder on the underlying crust. Looking back, the others following us didn't seem to find it such fun. Then I survived the 30-35 degree breakable crust better than I expected, and . . .
We had a decision to make. We agreed that most of snow on our SW facing ascent route on the other side of the ridge would be good, but I felt that the long straight mostly 25-30 degree slope would be a bit boring. And then when it reached 2000m altitude it would turn directly south, so the lower snow would be mushy earlier. But the alternate run which started directly south would lower turn SW, so the lower snow might hold good longer.
We later noticed that all the other parties crossed the ridge to ski the more reliable and straightforward SW-facing slope which had been our ascent route.
Great descent, but tricky: We chose to ski directly South. Immediately I was glad to discover that the crust lower on the 30-degree slope was no longer breakable. Then some moderate fun skiing thru some humps, and then we had to find a way through the cliff bands, which led to one tricky move.
Then a flat section which I kept gliding thru by contouring on the SE-facing slope to its right. Then into the gully for a ways down to a knob. Found a narrow snow chute on each side of the knob, and we choose the right (N) side as having a wider approach. Another broad moderate slope. Then Gi's edition of the Disentis 1:50000 map seemed to indicate we should go North from the creek to reach the Val Russein valley, which sorta worked, but looking back we felt it would have been easier to finish more South from the creek.
Note: I sorta doubt that this alternate descent route will be skiable in early May in a normal snow year. Even if there are tracks down it already, it doesn't mean it was fun. Maybe the photo in one of the guidebooks suggests a different route thru or around the cliff bands than we thought we got from our edition if the map -- be good to learn more about that. Also, I would be sure to start down early to allow time for re-climbing in case my descent got blocked by cliffs, and early enough so the snow would not be so mushy that it would very difficult or dangerous to re-climb. (? might also be good to be prepared to abseil / rappel ?). Or when leaving the Planura hut and descending south from the Sandpass, might consider descending south lower than 2000m, then climbing up this alternate descent route -- but looking back upward at several times, Gi and I did not think that the skiable line was evident from below (though it hadn't been so evident from above either).
After that we were on the main Val Russein descent, joining lots of other skiers who had come down from our ascent route. Everyone was staying on the east side of the creek, and continued on the east side all the way south until the snow ran out and the hiking turned into a forest road. Pleasant to be hiking alongside the creek, but still it was a long walk down to the road (but worth it). Then we drove my car back to the parking at the base off the Disentis Bergbahn. I noticed later that two German skiers took a taxi back to their car parked at the Disentis Bergbahn.
Engadin - Bernina - Julier region
Great ski tour with lots of variety and excellent fun skiing in the main run [ photos ]. Most people don't ski it from the summit, but in a big snow year some people do -- including Gi.
I think Piz Platta (3392m) is the highest peak in the Julier Alps. It is west from the Julier pass road which is the main route between St Moritz and Silvaplana in the south and Tiefencastel and Chur and Zürich in the north. Piz Platta offers a big view. The only higher peak to its north is Tödi (about 20 km to the northwest) -- actually there is no higher peak in the Alps directly north from Piz Plata. The Rheinwaldhorn is about 15 km to the west. To the east, Piz Güglia is not quite as high, but very dramatic, and higher Piz Kesch is about 12 km to the northeast. Directly south from Platta there is no higher peak in the Alps, but about 8 km southeast there is Piz Corvatsch and beyond it the famous Bernina group.
We started from the main Julier pass road by walking across the dam (1680m) of the lake Marmorera then up the hiking trail. After about 200 vertical meters we reached snow. It had a crust and with deep mush underneath, pretty bad for breaking trail, and we had no desire to ski down it on return (though we could see downhill tracks and later heard that in better snow conditions lots of touring parties use it for descent). We reached the top of our first climb at 2410m and across the valley got our first view of the Piz Platta intimidating. Then we skied a moderate slope down into that valley to about 2200m at the bottom of the main climbing route. The climb on skis around the east and south sides of the peak turned out to be straightforward and not as steep as I feared. Then we hooked back east to the bottom of the south chute, where we found lots of skis deposited. I told Gi I wasn't going to ski it and instead I'd take pictures of him.
Gi put his skis on his pack and started booting up the chute, said it didn't seem to bad, so I put my skis on my pack and started booting up also. Seemed to me like the lower section was about 35 degrees, with a 40 degree crux to get around some rocks and then less than 40. Climbing seemed easy to me just with boots and ski poles, but I talked with other skiers coming down and they said it had been icy when they started earlier and they were glad they had brought crampons. But the snow didn't look like fun, so I turned back at the middle of the lower section, put my skis on, and indeed the skiing down was not fun, and I continued to skiing to a viewpoint for photos, far away from the chute.
Gi skied it off the summit, looked to me like he was being more careful on the upper section than I would have expected. When he got around to me, he said that the snow had been tricky up high and that I probably wouldn't have enjoyed it. (I saw another chute on the southeast side of the peak with one set of tracks in it, as well as lots of exposed rocks).
Then the main ski run on the south and southeast side of the peak was very enjoyable with various options and steeper and gentler sections down to about 2200m. We turned north, gentle for a ways, then moderate skiing down (in mushy snow) to the big flat of Plang (1950m). We loosened our boots and bindings, skied across the flat to the village of Tga, and stopped for a snack at the Tgamona da Skis Piz Platta (a.k.a. Piz Platta ski hut) with a great view of the unskiable side of the Piz Platta.
I'd guess some ski tourers sleep there at the "Piz Platta ski hut", to break up the +1900 vertical meter climb into two days.
The forest road below Tga held snow very well, with only a few gaps where I carried my skis, so that was another fun part of the tour. Then it was a short hike down to the main Julier pass road at the village of Mulegns (1486m). We walked a kilometer up the road to the village of Sur (1538m) where we'd left our other car.
It was about +1900 vertical meters (+6200 ft) of climbing in two sections the way we did it. It would have been about the same height difference (but as one longer climb with more gentle sections) starting lower from Mulegns by way of the Piz Platta ski hut in the village of Tga.
Gi and I started from lake Marmorera and finished at Mulegns, though I've heard that many ski tourers do it the opposite way. What I liked about our way was that we got this intimidating view of the peak on our way up, then a pleasant little descent before discovering that the main ski climb wasn't as hard as it looked. Then on descent we got to enjoy a nice snack at Tga as a reward, and finish with the fun easy skiing down the forest road.
I stayed the night before (and after) at the Hotel Alp Flex in the village of Sur (on the Julier pass road about 5 km north from Bivio). They took good care of Gi and me. The village of Sur is between the Piz Platta on the west side of the road and the Piz d'Err (which we also thought of skiing) on the east side of the road -- which I think are the two highest peaks in the Julier mountain group which have ski tours on them. It's also very close to the Piz d'Agnel which Gi and I skied a few years ago in February and finished our tour by skiing down to the lake Marmorera whose dam is just a kilometer up the road from Sur. I met two different parties of German ski mountaineers with cars who stayed there instead of in Bivio.
Piz Bernina by the Buuch icefall
Skiing the Buuch icefall and also climbing to the summit was a great adventure, and we had perfect weather and good snow conditions. Most of the non-gentle downhill-skiing sections were fully-tracked already (after the four-day holiday weekend) -- so the overall skiing wasn't so good. And although the Piz Bernina (4049m) is the highest summit in the eastern Alps, I didn't find peak itself all that spectacular (from a distance).
But the peaks around it are very spectacular, and so are the seracs on the Buuch icefall. The navigation to and thru the icefall is rather interesting, also the navigation and variety of climbing to the summit by the Spallagrat. The gentler sections of skiing were nice, and I was glad to be able to ski all the way out to the train station. Of course it was just great to be out touring in different light conditions over so many hours of a pretty day.
Although I was glad to be able to climb to the summit, I think it would have been a great ski tour without that.
I left my skis around 3750-3800m -- I did not see any ski tracks higher than that (though it was obvious that lots of people had recently skied thru the Buuch icefall lower down).
Some people report that pushing with the poles doesn't help much, some experts recommend not pushing on the poles at all. Sometimes when I measure my time in climbing I've found adding pole-pushes can even make me a little slower.
This seems counter-intuitive, since lots of people would think that adding another muscle move to help the legs push would make climbing on skins faster or easier or both. I'm pretty convinced that pushing on the poles in the way I do it helps me go faster sometimes when conditions are favorable for it. But I think it's worth thinking about why many times the way other people do it does not help them.
How well poling works depends on several different factors.
(a) snow conditions are the most obvious problem. In soft deep snow the poles mostly just compress the snow.
Also it's difficult to predict how far down the pole will go in each push, so it disrupts balance and rhythm.
It's not surprising that experts who guide clients in regions known for consistent powder snow often advise not pushing with poles.
(b) poling to help the legs push the weight of the body up the hill does not address a key performance bottleneck for the legs: the extra weight of skis-boots-poles tends to make the main leg muscles operate at a lower turnover frequency or shorter range-of-motion than they are well-trained from other activities like walking, running, bicycling.
Multi-day tour: Climbing a steep slope carrying a heavy pack for a multi-day tour might be applying "peak force intensity" stress on the main leg muscles -- so they might need some help from the poles to take some load off them. In that situation, the advice might be to not push on the poles in more moderate climbing sections where the legs don't need the help -- to save the pole-push muscles for when they're really needed.
I saw a thread on TelemarkTalk about "efficiency" in skiing up hills, which had lots of stimulating ideas for skinning technique.
Only one person on the thread offered a definition of what kind of efficiency they were talking about. (and it was a smart definition, but not necessarily one shared by other contributors in the thread).
The obvious definitions of "efficiency" for climbing for skiing are:
I could also imagine some people defining it as the largest vertical distance for a given amount of fuel consumed. Or perhaps as the largest vertical speed for a given rate of fuel consumption (though this last is pretty similar to "most propulsive power output").
I could also imagine some people defining it as the largest vertical distance for a given amount of oxygen delivered to the bloodstream. Or perhaps as the largest vertical speed for a given rate of oxygen delivered to the bloodstream (though this last is pretty similar to "most propulsive power output").
The implications for technique are pretty similar for either kind of efficiency, since consumption of fuel and consumption of oxygen pretty much go together.
What kind of efficiency matters or not depends on the skier and the situation.
On the skier, because:
The big leg-extension muscles which provide the main forward and uphill push on the overall mass of the body are typically well-trained from other activities (bicycling, walking, running), while the muscles need to lift the weights on the feet forward and uphill are not well-trained. So the turnover frequency and/or range-of-motion distance that can be sustained by the muscles to move the weights on the feet is much less than what can use the capacity of the big leg-extension muscles. So for most backcountry skiers, those big muscles can easily get as much fuel and oxygen as they need. The problem for the muscles to move the weights on the feet is not lack of fuel or oxygen -- it's lack of size and training to deal with their assigned load.
Not that these skiers would hit a 100% VO2max rate, but that they would get close to a "Lactate Threshold" situation, where there's partial or temporary anaerobic functioning in some local specific muscle fibers, even though the total oxygen volume rate capacity of the central cardio-vascular system is sufficent to sustain 100% aerobic function. This locally partial or temporary anaerobic funtioning is not sustainable, which is why it "oxygen efficiency" only applies to short tours.
but this does not seem likely, because the same deficiencies also applied during the training of each and all of the muscles, so I'd expect that the proportions of performance capacity among the muscles are similar to without any oxygen-delivery deficiency.
On the situation, because:
In short races, oxygen-delivery is going to be a key performance-limiter (as it plays a role in determining "Lactate Threshold" power level).
In very long races, fuel ingestion and delivery is going to be a key performance-limiter.
Fuel ingestion and delivery is also important for recovery from hard races (or big tours).
If "fuel efficiency" matters, then fueling matters.
One thing that confirms my suspicion that "fuel efficiency" usually doesn't matter is that most backcountry skiers don't fueling seriously (compared with triathletes or cross-country ski racers or long-distance bicycle racers).
?? [ more to be added ]
Sierra ski touring trip from UK
08feb4 on a UK club discussion group
Thinking of going on a ski tour in the Sierra's (california) this year. Trying to figure out exactly what route. Would be grateful for any advise from people who have been - considering May - is this too late?! Let me know!
There's two helpful guidebooks with tours of various lengths (up to a week) and difficulties: Richins and Moynier. If you like paper maps, I find the Tom Harrison series for the Sierras to be good for ski touring. There used to be a website of multi-day tours. There are several experienced Sierra ski tourers (many of them not telemarkers) on TelemarkTalk.com forum who are likely to answer questions, especially if you give them a hint about what difficulty level (slope angle, vertical climbing per day), and style (high base camp, high traverse, single-day peaks + descents from valley campsite, etc) you're looking for . . . and which region.
The Sierra of California are a big range, and there's three or four very distinct regions in the Sierras, so it helps a lot if you say which one you intend to focus on: (a) Lake Tahoe (near Reno airport); (b) southern Eastside (Bishop and south); (c) northern Eastside (Mammoth Lake to Bridgeport); or (d) west side (closer to the big cities and airports).
I live in USA and I've done all but one of the recognized multi-day tours in regions (b) and (c), plus a couple in (a); and skied lots of the 4000m peaks (there's so many it's hard to guess what percentage). I think (b) and (c) are great touring regions, at at time with a decent snowpack. In springtime, they're one of the best bets in the world for stable snowpack, nice skiing on corn surface, stable predictable weather -- if they are taken with a flexible approach.
Trying to figure out exactly what route.
That's not the approach I and most experienced skiers I know take with the Sierras. If that's how you want to play the game, I strongly recommend that you hire a local guide service (you might want to try Robert S P Parker).
Also, unless you're engaging a local guide service, I recommend renting a car (rental costs and gasoline tend to be cheap in USA compared to Europe). Also there's some nice places to car-camp down in the valley (and I assume you're bringing your own tent and stove and sleeping gear), but the campsites can only be reached conveniently by car. Public transportation from the airports to regions (b), (c), (d) lacks convenient schedules. There's no "post bus" to anywhere near most ski-touring trailheads. So renting a car could easily gain you two days of skiing as well as save you money on hotels.
considering May - is this too late?
early May is one of my favorite times for the Sierras -- in a normal snow year. If snow looks good I'll hope to get there again this year. Three years ago was a big snowpack and I did some great tours in early May: http://www.roberts-1.com/t/s05/si/e . But other years May can require lots of hiking and carrying skis to reach snow-line, then taking off skis to cross explosed south-facing rocks even after up high. This year the latest long-term forecast I saw for April and May was unpromising (dry + warm). Currently snowpack is a bit below average (which is OK).
I'd suggest delaying commitment. Long-term forecast is more promising for the Cascades of Washington, where skiing the volcanoes and other tours around there can be good in May (or June) -- the Seattle region shares the weak currency and cheap petrol of the Sierras (but not so much the stable weather and snowpack).
I suggest: Purchase the guidebooks and maps, then ask some more specific questions on TelemarkTalk forum (could also check Teton Gravity forum for Sierra ski-tourers).
Something I occasionally wondered about over the years is if it helps to raise the shoulders on each step -- or is it better to keep the upper body more quiet and focus on pushing with the leg muscles (with some on with the arms pushing on the poles)?
Now I'm coming to think that raising the shoulders does help -- in two ways:
(1) uses the back-extension muscles to move the mass of the head + shoulders + upper torso upward against gravity . . . (a) which is part of the goal of climbing; and (b) which builds gravitational potential energy, which can be used to push the skier forward if the mass is allowed to drop while pressing on the poles and the poles transmit the force into the ground.
(2) prepares the abdominal-crunch muscles to push the torso downward (and perhaps backward) against the poles, which pushes the skier forward and upward if the arms and poles transmit the force into the snow. Raising the shoulders prepares by "recovering" the torso into a straighter configuration.
Key point from (2): Don't just "hinge" at the hips -- also "curl" or "crunch" (and un-curl and un-crunch) in abdomen.
Key point for both (1) and (2): In order to get the full benefit, the arm must transmit the downward force from the torso and shoulders into the poles. If the arm "collapses" as the shoulders move downward, then much of the benefit is lost.
It's usually more important for the arm to do a good job of transmitting force from the the torso than it is to add pushing motion of their own. Watch out for and avoid: arm initially collapse as the shoulders drop, but then extend to push the poles. Instead keep the upper and lower arm rigid as the shoulder drops to press on the pole. If the arm muscles still have the strength to make an independent pushing move after rigidly transmitting, that's good also but less important.
In soft snow the problem is that some of the energy from the torso-shoulder moves will go into compressing the snow instead of moving the skier forward. A possible strategy is to try to pre-compress the snow some using only the arm muscles, before the force of the shoulders dropping comes down onto the pole.
Raising the shoulders all the way to vertically above the hips is likely not helpful, at least not for skiers well-conditioned for climbing on skins. Two reasons: (a) A higher percentage of the force from the abdominal-crunch move will be transmitted directly into propulsive work if the shoulders are more forward (which requires that they be lower); (b) Raising the shoulders all the way to vertical may slow the frequency of the leg-pushes, so the total power output will be lower (since most skiers have more powerful leg muscles than back muscles).
more . . .
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