Possibly the best way to learn how to ski faster (which can often translate to being able to ski more efficiently at a slower speed as well) is to ski head-to-head against someone of similar or faster speed than you.
In order to get the most technique benefit out of it, it is important that the effort be all-out (100%) or close to it, so that you can’t simply “try harder” and keep up or get ahead just by muscling it or thrashing at a faster tempo (not that there’s anything wrong with putting lots of power into your kick or poles, or skiing with a super fast tempo…it’s just that in order to isolate the technique factor, effort level has to be neutralized.)
So, here’s one kind of drill/workout you can do with a friend (or 5!) that should give you a great opportunity to really hone in on what exactly it is that makes you go faster vs. what just “feels” faster or what might just be wasted effort. The amount of instantaneous feedback you will get while you do this is staggering! You can instantly, sometimes almost unconsciously learn a great deal about how to move and what you need to do to ski more effectively.
-Find a good wide trail (or a stadium if you are going with 2 or more people.)
-make some kind of starting line (this could be drawn with your ski or pole, or use a hat/glove/jacket on either side of the trail.) Make a similar finish line about 100 to 200 meters down the trail (about 10 to 20 seconds worth of top-speed sprinting.)
-Start with your toes behind the line and if possible, have someone yell “go” for you so you or your friend doesn’t have an advantage. (If no starter is available, set your watch to a 15 or 20-second countdown and don’t watch it, that way you can both - or all - wait for the beep like a starting gun. Whoever has the watch should be in the middle, or if it’s two of you, make sure the watch-to-be-used is the one that’s closest to both your heads! Ex. if it’s on the left arm, have that skier stand to the right of you.) Make sure you are both/all going to have your own imaginary lane with plenty of space to ski side by side without interference. You should both/all have room to go for it!
-when the “beep” goes off, give it your absolute best sprint to the finish line. As you go, try to experiment with different ways of skiing and see what things make you gain on or get ahead of your partner(s). For example, try skiing with a really fast tempo without worrying so much about putting tons of power into each pole plant or kick. Then, try skiing with TONS of power and don’t worry about trying to have a fast tempo. Or break it down into very small specific things such as getting your elbows higher/farther forward, planting the poles more vertically, getting in a deeper stance with more ankle flexion, getting the hips farther forward, really coming DOWN on the poles vs. staying more steady and lateral with not much up-and-down motion, following through with the poles more, following through with the poles less, applying most of the power at the beginning of the pole or the beginning of the kick vs. applying most of the power at the end of the kick or end of the poling motion, looking up the trail, looking down, thinking about cheeseburgers, thinking about salmon, etc.)
The idea is to do this a bunch of times…anywhere from 10 to 30 in a single workout. Do a sprint, then give yourself plenty of time (1 minute or up to 4 or 5 minutes if you need it) to FULLY recover, then line up and start again, and try something different! You can force yourself to ski a certain way for the entire 100 or 200m sprint, and then do something differently on the next one, and see which one you did better in, or you can try different things within a single sprint and try to see what makes you go faster relative to your partner(s). This can be tough to do in a 100m sprint as it goes by so fast, but it can be done!
And, this same idea can be applied to longer speeds / intervals, whether it’s a 30-second, 1-minute, 2-minute, 4-minute, 5-minute, 8-minute, or 10-minute interval, or a race! Anytime you can go all-out, head-to-head with someone who is your speed or a little faster, you can learn and improve a ton!
The advantage with doing shorter (10 or 20second) sprints is that to some degree at least, you take fitness out of the equation and it becomes more about just how well you are able to turn your effort as a human into speed across the snow on skis.
And, even if you never plan to race a sprint race and don’t care about being quick off the line in a mass start or improving your final 100m dash to the line at the end of a race, doing these head-to-head sprints can still be extremely helpful for your racing or general skiing enjoyment because you will learn the feel of, (or as Jeff Schloss would say, they teach your body to) use quick motions.
Even at a super-easy fun training pace or a 50k marathon pace, you can go faster for no additional effort if you use quick, precise movements with total relaxation in between, as opposed to long, big, slow pushes. If you get the feeling of that quickness and precision in those speeds, it is easy to apply it to your skiing at all intensity levels. And chances are, if you spend enough time doing those sprints, you are going to figure out (or the rest of you is going to figure out) a more ideal overall/general/”home base” body position to ski from, improving your efficiency and enjoyment at all speeds and in all distances.
Lastly, don’t be afraid to try these in all types of terrain, on corners, in soft conditions, firm conditions, slow conditions, fast conditions, skate, classic, no-poles, double-pole-only, or anything else you can think of! You will learn different things in each case, and then you can put it all together in the next race or your next Saturday ski!