The quarterback told The MMQB's Peter King he's done all that without having feeling in his fingertips on his right hand.
"I can't feel anything in my fingertips," Manning said. "It's crazy. I've talked to a doctor recently who said, Don't count on the feeling coming back. It was hard for me for about two years, because one doctor told me I could wake up any morning and it might come back. So you wake up every day thinking, Today's the day! Then it's not."
The lack of feeling in his fingers stems from a quartet of neck surgeries, which caused him to miss the 2011 season. While it's not exactly an unexpected side effect, it does make his production all that more impressive -- and might explain the increased frequency of Manning's wobbly ducks.
Manning also told King he believes the quad injuries that derailed his 2014 season stemmed from dehydration after catching a stomach bug prior to the game against San Diego, during which he incurred the injury.
"I threw up all night," he said. "Then, in the game, I moved to the right on a simple scramble and my quad cramped on me. It lingered. I couldn't shake it the rest of the year.
"I really studied it hard this offseason, whether it could linger into this year or whether it was isolated. I just think I got dehydrated, and that caused it. I don't think you can blame it on my age. It was just an isolated thing. I've made it through every other season, and this off-season I went through a state of the union physically, if you will, and I started training earlier and made some dietary changes."