No, in Frazier 3, Norton comments their weight in the ring and guesses that it is lower than the weigh-in due do dehydration before the fight. A very strong indication that at least the Futch fighters did this in the 70's.
So just a few studies of the correlation between weight exercises and power. These studies all measured an increase in rear hand power (but not in front hand, at least not concerning bench press) power after excercises such as bench press and squats: https://bmcsportsscimedrehabil.biomedcentral.com/articles/10.1186/s13102-022-00557-4 https://www.scitechnol.com/peer-rev...combat-athletes-a-pi-eC30.php?article_id=9355 https://journals.lww.com/nsca-jscr/...nship_between_bench_press_strength_and.3.aspx http://scielo.sld.cu/scielo.php?pid=S1996-24522021000200509&script=sci_arttext&tlng=en These two measured an increase in power after some exercises but not from others: http://www.thescienceofstriking.com...-resistance-training-load-for-punching-power/ http://www.thescienceofstriking.com...and-power-in-highly-trained-amateur-boxers-1/ This one found that specific boxing training increased weight lifting results: https://www.ksep-es.org/journal/view.php?number=768
Frazier likely had no clue what the event was even about other than a chance to go to a warm climate and have some fun .. Joe barely even went to HS let alone college and had next to no understanding of organized sport physical fitness training and as a result suffered a bit publicly but like Joe he shrugged it off and went on ... I doubt any of the other participants laughed in his face , that's for sure .. I do remember before their fight at some point in 83 or 84 Hagler and Hearns were both on the Superstars at the same time and both did pretty good athletically , even faced off in the obstacle course and Haggler just edged him but again both were impressive ... wish I could find that clip ..
An average teenage girl is very likely an overstatement. They are much lower body fat than teen girls & much taller, so their upper bodies look even thinner than they are. A teen girl should have even less muscle on their upper bodies. But that is merely a technicality, the general trend is correct! They also did not commonly have pretty muscular upper bodies for sprinters until the 1980's. Then they discovered that this could help.
I was talking cycling. They are still skeletally thin upper body. Even top pros are skinny like POWs.
I know you were speaking about cycling, I just added commenting on sprinters at the end. I just disagree that they have as little upper body muscle as POWS, or that a typical teenage girl could out lift them. They do not have much upper body mass, especially for athletes, I just find that too extreme. If you took an exactly average man & lowered his body fat % to that of a pro cycler, their upper body would not look much different. A little bulkier is all...
