Former Warriors and Kiwis doctor Chris Hanna said: "If you are binge drinking and you become dehydrated you are not going to play as well as you would have been able to in a test match. "We are talking about tiny percentages when it comes to beating the opposition at this level.
"Your ability is going to be reduced. It's just not sensible."
He said players could also have impaired judgment, dehydration and reduced ability to recover after training.
"If you consume alcohol in the first few hours after intense exercise, what you are doing is reducing your ability to replenish your muscles.
"I would never encourage binge drinking. However, it is important that the All Blacks keep doing what they have done to get this far."
Hanna said a single cigarette would reduce a player's lung capacity but it would also introduce carbon monoxide and nicotine to the player's blood.