thielges@uiucdcsb.UUCP (11/21/84)
I was wondering if any net.bikers who also cross country ski could relate some of their skiing experiance in biking terms. Specifically, I would like to know the physical effort needed per mile (aerobic and isometric) in terms of the same effort used in biking. Something like 'skiing 3 miles is like biking ten on a flat surface' or 'skiing up a 1% grade is like biking up a 4% grade' Actually, any helpful comments would be nice to help a biker evaluate c.c. skiing and to decide to try to take it up as a winter sport. Also, if you know how it works the 'bike' muscles to keep them in condition, please let me know. Bart Thielges
neal@druxv.UUCP (Neal D. McBurnett) (11/26/84)
It seems to me that x-c skiing is pretty close to running in terms of effort per mile. Of course your skill level, ski quality, waxing technique can make large differences, but the top runners and skiers are frequently within 10-20% of each other in terms of speed. Naturally, inexperienced skiers will be slower (and more sore...). So now you may ask, "well how do biking and running compare?". Again, depending on technique and experience, expect a slowdown factor of between 2.5 and 3 when you start running. This is even more difficult to specify. The rate of energy expenditure when you run is nearly linearly related to the speed with which you run, whereas when you bike, your effort is related to a cubic polynomial of your speed. Thus the effort expended when you run is quite closely correlated to the distance you run (regardless of how fast you run it), whereas the faster you ride, the more energy you expend per mile (assuming you're going faster than about 12 mph). As for hills, in all cases (to a first approximation), the extra effort required to go up a hill is determined by the effort required to lift you and your gear upwards against the pull of gravity. First, note that your bike weighs more than your skis, so hills are more of a problem on your bike from that standpoint. Furthermore, note that you are more efficient on level ground on your bike than on your skis (there was a great Scientific American article a while back which pointed out that the bicycle is more efficient than any other mode of transportation, man-made or in the animal kingdom). Thus you will notice more of a decrease in speed when you ascend a hill on your bike than when you ski (and more of an increase when you go downhill). As a rule of thumb, for casual biking, I find that a 3% grade cuts my speed in half, but I'm sure that it wouldn't slow my skiing down that much. If anyone wants harder numbers and equations, I can probably supply them. Finally, as for muscles, I frequently pull my groin muscle when I ski: it is stretched a lot in x-c, but not at all in biking. -Neal McBurnett, ihnp4!druny!neal, 303-538-4852
jans@mako.UUCP (Jan Steinman) (11/26/84)
[All references to "skiing" are to >complete< skiing, not the lift kind!] In article <uiucdcsb.16200079> thielges@uiucdcsb.UUCP writes: > ...(what is) the physical effort needed per mile (for cross-country skiing) > in terms of the same effort used in biking. Nordic (a.k.a. "cross-country) skiing is generally regarded as having the highest >potential< for caloric expenditure, which often gets overemphasized. (Cross country skiing? That's a lot of work!) But it also has one of the broadest ranges in energy usage. Simply shuffling around at an easy pace consumes little more energy than walking (150-250 calories per hour), while racers in top condition burn energy at a rate greater than any other athelete. (1000+ c/h) An average skier probably burns around 250-450 c/h. I don't know how this compares to biking, and the whole thing is pretty individual, anyway. If you are an aggressive biker, and will be an aggressive skier, I suspect you will burn more energy skiing, simply because: >...how it works the 'bike' muscles to keep them in condition,... You are using more muscles when you ski (especially if you ski correctly). Nordic skiing is a whole-body exercise, which it shares with swimming, wrestling, and very few other exercises. Although both biking and skiing are quadricep (sp?) intensive, skiing involves the back, stomach, shoulder, and arm (and even facial ":-)") muscle groups in a coordinated manner seen in no other sport. If your intent is training for biking, the upper-body work will probably be counter productive, but it certainly is great for over-all fitness. I personally find that cycling tends to increase leg muscle bulk, while skiing improves leg muscle definition. Also, the grecillous (sp?), the pronating muscle that runs from the groin to the inside of the knee, is relatively unused in biking and may be painful after your first few snowplows. Unlike bicycling, nordic skiing is technique intensive. (No flames from cycling technophiles, I stand by the statement that there is more to learn about skiing efficiently than pedalling a bicycle.) To get the most from skiing, take a few lessons from a PSIA Certified instructor. (A biased opinion -- I'm a certified instructor with eight years experience.) After a while, you may find yourself riding a bicycle to keep in shape for skiing... -- :::::: Jan Steinman Box 1000, MS 61-161 (w)503/685-2843 :::::: :::::: tektronix!tekecs!jans Wilsonville, OR 97070 (h)503/657-7703 ::::::
harris@uiucdcsb.UUCP (11/28/84)
As an exercise sport in the C-U area, XC is very impractical -- it just doesn't snow enough (if last winter is any indication). Of course, the roller variety might be suitable if the roads are clear. Or, perhaps I just don't know how to wax for grass and gravel. Jon Harris
rogerh@arizona.UUCP (Roger Hayes) (11/28/84)
I agree with Jan Steinman, that skiing is more of a whole-body workout, and has a wider range of energy expenditure, than biking. In support of the point that technique is more important on skis: if you're a graceless bicyclist, you waste energy. If your technique on skis is bad, you won't be able to climb hills or turn corners -- strong impediments to making forward progress. I'd like to add that skiing feels wonderful. If done right (ie fast), it stretches all the muscles as it works them, so you end up feeling like a rag doll. It's great! It is somewhat less convenient than cycling, at least in Arizona, though. Roger Hayes Tucson, Arizona
jans@mako.UUCP (Jan Steinman) (11/29/84)
In article <druxv.1367> neal@druxv.UUCP (Neal D. McBurnett) writes: > It seems to me that x-c skiing is pretty close to running in terms > of effort per mile... the top runners and skiers are frequently within > 10-20% of each other in terms of speed. WRONG! That makes about as much sense as saying that a Volkswagen and a Volvo will use the same amount of gas when travelling the same speed! Running and skiing are as different as running and cycling are. The speed- energy curve you describe for cycling (cubic polynomial) really fits skiing like a glove! (Remember fluid mechanics? Just what is that stuff your skiis are sliding over?) The speed-energy ratio of varios sports cannot be so simplified. (If you're really interested, I'll pull out some sports-medicine papers showing energy expenditure for various levels of expertise in various aerobic sports.) >As for hills, in all cases (to a first approximation), the extra effort >required to go up a hill is determined by the effort required to lift >you and your gear upwards against the pull of gravity. First, note >that your bike weighs more than your skis.. Again, a gross simplification. Are we talking gravel or asphalt? Nice set tracks or four feet of mushy snow? Is the skier wearing a parka, carrying a lunch and some water, using metel-edged mountaineering skis (all of which can easily equal the weight of a bicycle. Generalizations based on such oversimplification are not valid. I think it is fair to say that skiing efficiency and work-out value is more affected by external conditions than cycling, and is correspondingly more difficult to quantify. There are certainly times when a 3% upgrade will cut speed in half, and times when such a grade's effect is nil. The wide variety of conditions and situations is what makes XC such an interesting (frustrating?) sport! >Finally, as for muscles, I frequently pull my groin muscle when I ski: >it is stretched a lot in x-c, but not at all in biking. Granted, as I mentioned in my original posting. Some one has since mailed me that a little roller skating in the bicycling season will keep the grecillous (sp?) in shape. A lot depends on point of view and individual preferences. Sports literature shows a higher injury rate for runners than XC skiers, and the injuries are generally more severe. (I have yet to hear of a top XC skier requiring knee sugery.) Skiing is quadricep (sp?) intensive, which maps better to cycling than the gastrocemius (sp? It's been a long time since anatomy!) intensive nature of running. If you have the snow, I still beleive skiing (the original kind) is one of the better things a cyclist can do off season. -- :::::: Jan Steinman Box 1000, MS 61-161 (w)503/685-2843 :::::: :::::: tektronix!tekecs!jans Wilsonville, OR 97070 (h)503/657-7703 ::::::