The guy who supposedly gave Manning the HGH has recanted the entire story to both Al Jazeera and ESPN. he said some other person was asking him questions trying to get into the business, he decided to make some stuff up to see if the guy had any idea what he was talking about. One of the things he made up was the HGH and Manning, the guy then went to the media naming the guy who made it up as the source.
No idea what's true or not but right now the source is actually denying it's true.
They named a bunch of other athletes including Clay Matthews(painkillers) and Julius Peppers and Mike Tyson