I have seen the pics of the scary skinny guys like Rasmussen and others. I think the guys to look at are Indurain, Merckx and Armstrong. These guys are big powerful men who optimized their weight for racing but produced a lot of power. They killed the Rasmussens of this world in the mountains and the time trial.

Here is a pic of Merckx at the track in 1972 setting a world TT record.



Check out his back and glutes. That is where he generates his power in the TT and on the climbs.

Indurain (5 TdF wins in a row) was 6' 2" and 175. He massacred the "skinny guys" on the climbs. And Lance was 5' 11" 163ish.