Carbonation does effect you but I believe sometimes its effects are more in a persons mind than in reality. The truth is if you're trying to shave .1 seconds off of your 40 yard dash time then stop drinking carbonation. If you're trying to shave 2 minutes off of that 3 mile hike then don't drink it. Because thats about all the effect it really has. We all drink it in moderation in camp and don't notice any real difference. I used to play college football so I did stop drinking it altogether for years, it doesn't make a real big difference. Its more of a fine tuning thing than the difference between being able and not being able.