"I wanted to give it one last hurrah and go somewhere that was a little bit hotter. In Boulder I had one day of rain in eight weeks. Temperatures in the last 70 days were all over 32C.
"The weather has been fantastic. It's been a massive help when you are training day in and day out.
"I have had a solid eight weeks of training at altitude that has been fantastic, with no interruptions. Then the altitude effect has allowed me to push a bit harder. It takes two to three weeks for that altitude effect to benefit back at sea level. I've been here in Hawaii for two weeks now so I should be firing on all cylinders.
"At 40 years of age I am still going strong and going well. I don't know if this is the last one here. Never say never. But I wanted to have a bloody good push. My results over the last few years here have not been the norm so I am really, really looking forward to putting a good performance on the board."
Brown is one of three New Zealanders in the elite start list. Another 30 are in the age group field to take on the heat and strong trade winds that are part of the cauldron of Kona.
Joining Brown in the elite field is fellow Auckland and seven-time Ironman New Zealand champion Jo Lawn, and Wanganui's Gina Crawford. Lawn, like Brown, is chasing a strong performance after two indifferent displays in 2010 and last year.
Last year her focus was on the Ironman 70.3 world title in Las Vegas, where she finished fifth. In Hawaii, she faded to 32nd without specific Ironman preparation. This year the aim is Kona but along the way she again managed a highly creditable fifth in Las Vegas.
"I surprised myself," she said. "This race course is all about strength and toughness. I was in preparation for Kona so I was unsure how I would feel compared to last year when my focus was 70.3. So I felt amazing, Ironman training is perfect for this race."
Like Brown, she is ready for a strong performance.
Crawford won seven iron distance titles, including Ironman New Zealand in 2009, before taking time out for the birth of her son Benji in July last year. Since her return to the sport in January, Crawford's performances have been remarkable.
She has never been further back than seventh, and picked up wins in two iron distance races including Wanaka, second in Ironman France and fourth in European long distance championships.
She comes into Kona after victory with a sub three-hour marathon at Henley near London.
The men's race is laden with talent. The battle will be between Australians Craig Alexander and Chris McCormack - who have won the past five Kona titles between them - Belgian Marino Vanhoenaker, Germans Andreas Raelert and newcomer Christian Kienle and American hope Tim O'Donnell.
In the women's event, Australia's 2010 winner Mirinda Carfrae is favoured, with Noosa-based Swiss star Caroline Steffen and British world 70.3 winner Leanda Cave.