My helmet makes my neck tired
My legs get tired skiing with taller Bears because they leave the bar up
Went to PSIA Academy long ago @ A Basin. They took us all down to DU and ran us through a sports testing lab. Their object was testing as many different people from as many different sports as possible. This was in the 70s' , conditioning was not a real high priority for us in those days. We were put through some really interesting tests, in a standard battery that they put all their participants through. They told us the testing was in its 3rd year then, so a very wide test group.
Our little band of gypsies set the high marks (for that time) in three different tests: static leg strength, eye foot speed, and one other leg strength test (don't remember what it was). This was out of about 12 tests.
The static leg thing was amazing. They sat you on the edge of an examination table with your lower legs hanging free. A 600 lb test cable was attached around 1 leg above your ankle using a padded collar with no cable slack. Then you would try to straighten the knee out while measuring the pull you applied. The guy who set the record sat there and BROKE 3 cables, 1st time the testers figured it was a stretched cable, by the 3rd time not so much.
If a bunch of PSIA weenies could match up that well to collegiate, Olympic and pro athletes then skiing is athletic.