[screye]

Yeah, I wonder if they compared dancing to highly dynamic (non repetitive) sports, then would the results be different.

Soccer for instance, demands continuous concentration and is as taxing mentally as it is physically, esp. in certain positions. This seems to be similarly true with sports like hockey, basketball, tennis, etc. Not sure how much of it applies to stop-start sports like baseball, cricket and american football.

Climbing requires deliberate control over muscles, breathing, coordination and concentration, in manner that I haven't seen in any physical activity.

That being said, looking at some of the dancers I know, dancing can be incredibly physically taxing on its own.