We want you to be snappy not sweeping. How to be snappy:
1. Compact at pole plant - look at the elbow angle at pole plant (90° is a good rule of thumb. Many top skiers are closer to 80°.
2. Do not finish with back parallel with ground. 45-60° is a good rule of thumb. Once you get to 45° snap back into back extension.
3. do not allow shoulders to extend so that arms are pointed backward down the track. Instead, Once your hands pass your knees, SNAP them back! Really. Swing your arms forward powerfully. This momentum is what lifts your heels (heels are NOT lifted by "standing on one's toes")
Q: Why snappy? A: Your poles are done generating a propulsive force at #4 in the top image. If you allow your arms to continue to swing rearward, this is time you could be snapping them back forward. So snappy poling allows you to have a higher turnover at the same maximum angular velocity at the shoulder because you have a shorter (snappier!) range of motion.
Q: But doesn't a good follow through allow more forceful poling? Good question. Unquestionably you can increase the propulsive force at this point in the cycle with a hard push at the end. The problem is, at that point in the cycle your elbows are very extended so your output lever arm (the length of your jaw!) is long and it takes a huge input force to eke out a small output force. So is it worth it?
Some other notes about the two figures. Note in the top figure the poles are planted more vertically. This is good. You do not want to plant them vertically, but if your body position is good, then the poles should be nearly vertical when planted.
Some snappy videos!
(ok there is a little bit of sweeping poling, especially at the beginning of the ladies video. Is that Kikkan? Snappy poling doesn't require hyperfast angular velocity. Check out the bottom video of the Swedish ladies at about 4:50. Indeed look at the men just before that. The point is, at the same maximum angular velocity your turnover - and therefore force phase - will be higher with snappier poling)
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