Yeah I'd be interested if someone did analysis on this, I tend to suspect they aren't linked either but I really don't know.
I do know overtraining can cause a loss of muscle, built up fatigue on the body, and a loss of performance. So playing players too many minutes can really hurt their effectiveness on the court. Back to back NBA games lead to a weak product that is less enjoyable for fans to watch.
I'd love to see the NBA get rid of some of these games and eliminate tanking. That draft wheel idea sounded crazy at first but now that I've thought about it more I think it would make for a much better product.