First man I though of was Renel Janvier.
I worked the backstage at the 1991 Ironman Pro. I was to assist pros who showed up without an attendant and needed oil, etc. I was assigned to Renel. My gawd that man had the thinnest skin on any human I have ever seen in 60 years in this sport. I had to be careful not to tear his skin as I applied his oil. If he had any body fat at all it was not visible. He took 2nd to J.J. Marsh. Hard to believe but he was kept out of first because the judges in those days did not like the striated glute look.