"It's hard keeping up. Low-fat milk and lots of pastas and rice and that sort of thing. Lean meat and fish - obviously not cakes and pies. And lots and lots of water."
Ms Knowles said the players - who are training in the Eastern Bay of Plenty town ahead of their first match in Rotorua next Saturday - were an amazing bunch of guys.
"And they're huge. They make us all look like we're dwarves."
She said the beds at the holiday park were holding up well. But other hotels have swapped double beds for queen-sized beds, just in case.
"The standard bed is 2m-long and that's all that they've requested," said a manager at a North Island hotel set to host the Springboks.
"But we've actually moved in bigger beds to the rooms that the team are going to be in. I can just imagine a huge lock or something arriving and saying, what am I going to do?"
The players skew the normal range of weights and heights - only 22 players come in below the "overweight" threshold in the body mass index.
That is less than 4 per cent of 600 total players, and roughly one player per team. There are no All Blacks in that category.
The heaviest player - Ireland's Tony Buckley - is also about twice as heavy as the players tied for the lowest weight.
Georgia's Irakli Abuseridze, Japan's Atsushi Hiwasa and South Africa's Gio Aplon weigh 70kg each, and Buckley 137kg.
Forty-five centimetres separate the shortest and tallest player.
Most of the hotels said they had done something extra with their facilities and staff training to prepare for the World Cup.
At the Gulf Harbour Lodge in Auckland, manager Sonya Burton said teams were not allowed to communicate any special requests until they arrived.
But the current group of players had been pleased with the hotel, its facilities and its cooking - though there had been one unusual request, she said.
"We've actually had to take a bed out of one room. The player likes to sleep on the floor."
The IRB has demanded that hotels avoid talking about specific teams - but most agreed that the teams' movements were obvious.
"They travel in a very luxury coach that all the Rugby World Cup teams are to use. They are painted and decorated and they turn quite a few heads driving through Ohope," said Ms Knowles.
Size matters
Lightest
* Gio Aplon (South Africa)
70kg, 1.75m tall
* Irakli Abuseridze (Georgia)
70kg, 1.74m tall
* Atsushi Hiwasa (Japan)
70kg, 1.6m tall
Shortest
* Alexander Yanyushkin (Russia)
75kg, 1.65m tall
Heaviest
* Tony Buckley (Ireland)
137kg, 1.95m tall
Tallest
* Luke Charteris (Wales)
125kg, 2.06m tall
