This is Kylee, an Uphill Athlete Coach and Skimo racer. Yes, your observations of Skimo vs Ultra are what a lot of people have experienced. Although, it’s become quite popular to cross train for Ultra running with Skimo and vice versa they are actually really different beasts. As you probably guessed at the start of a Skimo race lots of people are pushing zone 4/5 so getting right into their anaerobic zone. It’s best if you can ease off the pedal a little bit off the start so that you don’t burn up in your anaerobic zone very quickly (1-2 minutes). I will say high end Skimo racers have a very high aerobic threshold and well-developed aerobic systems to be able to sustain a very hard effort for upwards of an hour. To your question about a warm-up one thing you could try for a 15 minute warmup is five minutes of upper zone 2 so fairly easy and then complete 5 x 30 seconds of hard effort followed by 30
seconds of easy skinning. The 30 seconds could be classified as an “acceleration” or “pick-up” effort the reasoning behind doing this is to get your leg and arm speed going and slightly tap into a higher heart rate zone so it doesn’t feel so shocking off the start. Finish with five minutes in zone two this should fire up your body to get ready for the demands ahead. Because you are tapping into your anaerobic zone possibly right off the start I would also advise ingesting some carbohydrate or energy snack approximately 20 minutes before the start. To improve at skimo long term, building a huge aerobic base but also sprinkling in some tempo or intensity efforts is important. Hope your season goes well!