Bathe, baby, bathe!
One of the most popular activities for the Romans was to bathe, which is great for hygiene… right? Well, bathhouses weren’t particularly sanitary as everyone (from all walks of life- slaves included) was welcome to take a dirty dip into the waters. Hundreds of dirty people cleaning off in the same water all day- you get the picture. If it makes it any better the baths were strictly segregated by gender.
Many were also not toned with a six pack like in some movies for precisely that reason. A nice bit of fat gives your opponent something to cut without a kill.
Die in the games*
And obviously in the the centuries of gladiatorial games there have been some exceptions and circumstances. But overall, I know what I'm talking about.