Fedor was 33 when he lost to Werdum and 34 when he lost to Bigfoot.
Yeah, most guys begin decline around 9 or 10 years if you actually looked around. Look at the thousands of fighters who declined and began losing around that mileage marker.
https://www.bloodyelbow.com/2013/7/...er-into-mma-fighter-longevity-does-age-matter
If you actually watched the fights, you would see Fedor was obviously slowing down before he ever even lost.
Guys like Cro Cop and Arlovski were 30 and 29 and were looking very good leading up to the Fedor fights. They were definitely not on decline. All those guys are still fighting too. Fedor beat them back then but they would be the favorites to beat Fedor in 2018. If that doesn't show how fighters change over the years there is no helping you with your narrow point of view.