If you see Dean Barker with a small plastic tube in his mouth during an America's Cup press conference, don't panic. It's not oxygen, as some fans mistakenly thought. It's also not vodka, though he'd probably prefer that.
He's re-hydrating, sucking in some isotonic fluid. It's all part of the science of nutrition which is hugely in play as the America's Cup teams battle it out for the Auld Mug.
Oracle Team USA's trainers reckon that their sailors chew up something like 6000 calories on a training run in San Francisco Bay. Emirates Team New Zealand's trainer, David Slyfield, doubts the calorie output is quite that great but agrees that the sailors' diets are managed to ensure optimum performance in such a taxing sport.
Tour de France cyclists, for example, have to take in even more. Britain's Bradley Wiggins, the 2012 winner, ingested something like 7000 calories per day to fuel his exertions.
So Team NZ chefs Harry Lynsky and Romeo Mitchell-Dowling are key people in the vital plate-to-performance equation.
"They are fantastic," says Slyfield. "They produce high-quality nutrition - and we eat what a lot of people eat in restaurants, though you won't find a lot of nouvelle cuisine portions here."
In typical Kiwi fashion, it's an egalitarian food regime. The shore crew, support crew, engineers and designers all eat the same tucker. There's no special diet for the sailing team but plenty of variety through carbohydrates, protein and other food groups.
"We don't count calories," says Slyfield. "The sailors make decisions on the quantity they eat. We give them guidelines but it's up to them.
"What we do is look at things like timing. Like we tend to split lunch [on race days] into two. They have something to eat before they go out on the boat and, when they get back, I am at the top of the ramp giving them some more to eat.
"I do that for two reasons - one, they get distracted by people asking them questions and other things. Two, you recover better when you eat immediately after exertion.
"Your muscles are far more receptive to nutrition in that period - so timing is important. You might forget and eat later and even take in the same amount of calories but you won't recover as well."
It's the same with drink, which is why you sometimes see Barker replacing his fluids during the press conference. It's not a nervous tic. He's recovering.
"First and foremost, it's hydration," says Slyfield. "We know that there can be a 1-2 per cent performance drop straight away if you do not re-hydrate."
There's been plenty of examples where athletes have admitted to being fatigued and having poorer decision-making faculties because they haven't drunk enough afterwards.
Slyfield and co may not count calories for their sailing charges but they do monitor weights.
The 11-man crew have to average 92kg (a total of 1012kg across the team) and they have some big men on board, the biggest at 116kg.
So they have reason to be grateful for smaller blokes like Ray Davies and Glenn Ashby - and grateful but careful when the chefs produce the odd luxury or two.
Like the day we visited the Team NZ base and a chocolate cake was plonked on the kitchen server fronting the dining room. We were nearly trampled in the rush.
"Well, says Slyfield, "you have to have some treats. You have to enjoy your food as well."
All for one and one for all
• There is no special diet for the sailing team but they have a variety of carbohydrates, protein and other food groups.
• The shore crew, support crew, engineers and designers all eat the same tucker as the sailors.
• Lunch is split into two on race days. They eat before going out on the boat and when they come back.
• The most important part of recovery is hydration. There can be a 1-2 per cent performance drop straight away if they do not re-hydrate.
• The 11-man crew have to average 92kg (a total of 1012kg across the team) and they have some big men on board, the biggest at 116kg.