My brother is a huge fan of the Joe Rogan podcast, even before Robb Wolf was a guest a while back (if you haven't checked that episode I recommend it especially to introduce others).
My brother mentioned how Joe Rogan had surgery to "fix" his deviated septum and how happy Joe was to be able to breathe so much better and feel his cardio improve.
I have never had great athletic performance, but my cardio and endurance has ALWAYS been especially poor. Eating a paleo has improved lots of things since I incorporated this lifestyle 2 years ago, but I have always been stumped why I get exhausted much faster than my less-than-athletic and non-Paleo friends.
I don't have sleep apnea nor am I normally loud breather, but am seriously considering surgery after an orthodontist saw my septum was abnormal in a CAT scan.