*smile*
This subject/debate is always interesting to many. Many of the answers already mentioned are spot on. Here's a little insight from a buddy of mine who has written for DC and Marvel:
"DC is NOTORIOUS for keeping character's "prowess maximums" a bit nebulous. They have historically wanted characters to be able to supersede their imposed restrictions for the sake of the ultimate display of heroism. Marvel, on the other hand is a bit more definitive in making the indication for strength levels (especially since the advent of the 'Marvel Universe' comic-encyclopedias). Marvel will, however, COMPLETELY change a character's strength/prowess levels in a HEARTBEAT if they feel it will somehow serve their purposes for a storyline...take SABRETOOTH for example. Originally, he was designed with "peak human" strength (too somewhat match Wolverine). After the first X-men movie, he was stated as having Class 10 strength (Superhuman ability to lift/press 6-12 Tons)."
Interesting, huh?
Well, with my background in Fitness Training, a college running back athlete can clean and press (lifting a weight from the ground and
pressing it overhead) his own body weight ten to twelve times on average; with a male gymnast, that number usually falls to seven or eight repetitions. With a female gymnast, that number falls to no more than five reps (on AVERAGE). With powerlifters and quite a few bodybuilders (both male and female), that number hovers at twelve to fifteen repetitions.
With all that said, we both came to the these conclusions:
Clean and Press Indications (1 Repetition)
Average, non-sedentary Human Clean and Press - 80 - 110lbs (1 rep)
Athletic Human Clean and Press - Body weight for 3 - 6 reps
Collegiate/Pro Athlete Clean And Press - Body Weight for 8 to 12 reps
Peak Human Clean and Press - 350 - 500lbs (2 or 3 reps)
(Most non-superhuman heroes fall in between the previous
two "Real World" categories)
Meta Human Clean and Press - 500 - 1000lbs
(Most of the Watchmen in the recent Film)
Low Superhuman Clean and Press - up to 1 ton
Class 5 Clean and Press - up to 5 Tons
etc, etc,
So, to address Darth's statement: Original Capt. America was just in the cusp of Metahuman (in an Avenger's comic, Cap has been displayed doing barbell curls with 500lbs). In the Ultimates, Ultimate Cap has definitely received an "upgrade" and is in the low-end of the
Low SuperHuman Clean and Press. In the Ultimate Avengers movie, I remember seeing Cpt. America "rolling upright" an overturned, military truck by himself (and without SERIOUS strain)...THAT is superhuman.