What would happen if a person ran a race and her muscles carried out alcoholic fermentation instead of lactic acid fermentation?

The alcoholic fermentation would produce alcohol and CO2 rather than lactic acid. This could be detrimental to the runner. I don’t know if the person would get drunk, though, theoretically this is
possible if the alcohol can get into the bloodstream but it could definitely cause some problems with muscle tissue, since CO2 would take the place of the oxygen we need.

Yes yes yes very good