It's not the color loss that is the issue. The change from a washed out color to the fully saturated color is instant and very noticeable right when the color comes back. If the color loss is in fact due to running fatigue, then it shouldn't switch back and forth while in a constant run, and make it a gradual change back to saturation when you catch your breath, not right when the invisible fatigue meter refills. Its just a minor graphics glitch so its not game breaking, but it is something they should look into in the future.