Physical Exhaustion - A Test For Virtual Reality

If I walk a mile or run a race in virtual reality, I do not feel physically tired or out of breath and my heart doesn't pound.
If I walk a mile or run a race in this world that I am told is reality, I do feel physically tired, out of breath and my heart pounds.
I do not know for certain that scientists will not one day invent 'virtual exhaustion' but, at this present moment in time, tiredness and the other signs of physical exhaustion: becoming out of breath and having a pounding heart are a discernible difference between reality and virtual reality.