You probably don't need a scientific study to tell you that consumption of sodas during and after exercise is bad, but here we are for some reason.
In a small study published recently, researchers at the University of Buffalo sought to quantify the effects of soda (Mountain Dew, specifically) on subjects physically exerting themselves in the heat. They found that consuming a soda during and after exercise reduced renal function and increased markers of AKI (acute kidney injury) as opposed to drinking water.
I'm sure you are scratching your head at this point. Why on earth does this matter? Who doesn't already know this?
The researchers were not intending to keep people from drinking a Coke during a strenuous session in the weight room, what they were intending to do is mimic some of the conditions of physical labor in the heat.
"What we are learning from this recent study is that soft drinks may actually inflict kidney injury in individuals who are dehydrated and have heat stress." Dr. Richard Johnson
Anyone who has ever spent a day on a job site working outdoors knows that a soda or two at lunch is incredibly common.
There is also a non-insignificant portion of the endurance training community that relies on high-carb, high-sugar fuels (yes, even including a soda on occasion) during and after long sessions.
So, the moral of the story is the common sense one...don't drink soda after you exercise but also pay attention to what you're drinking during long days in the heat.