I get most of my protein from booze ...?

My friend is a sprinter athlete, clocking between 10.7 and 11.2 for the hundred meters. I am a bit worried because as soon as his training ends, he goes with friends in a bar and drinks a few beers and even wine and vodka. He says he's ok as his coach advised him to at most 20 units of alcohol, and in the training season at most 10! His performance still improved this year, but not quite as much as before. He also says that he gets enough protein and goes with that and just another big meal in the morning. Is this regimen ok? I start feeling dizzy and get bad sleep even with 2 beers in the evening.