A refreshed Nick Willis is confident his "improvement curve is still on the way up" as the 1500m star plots to turn silver into gold at the London Olympics in August.

Last year was underwhelming by Willis' high standards as the Hutt Valley product faded badly to finish last in September's world championships final in South Korea.

But Willis – back home in New Zealand for a part holiday, part training stint – is well over the disappointment of Daegu and draws optimism from the fact that two months before the world champs he ran a personal best of 3min 31.79sec in Monaco.

"So that's the most satisfying part; despite my not so good performances at world championships I ran my personal best, so I know that the improvement curve is still on the way up," the 28-year-old said.

"So as long as I can stay healthy and get in some good training, there's no reason to believe that improvement won't continue. I would dearly love that [another Olympic medal], but there's still a long way to go and it really depends on how my training goes over the next three months.

"What I do February, March, April, May will really determine what my chances are. I've had some good fortune and some awful [2010 knee surgery] lately but I'd love to put myself up there."

The United States-based Willis and his American wife Sierra saw in the new year in the Bay of Islands with family before relocating to Wellington "with a stop-off in the Redwoods for a run".

Canny coach Ron Warhurst hasn't joined Willis in New Zealand as he starts his training regime but his brother, Steve, is back on board and has taken the stopwatch.

British training partner Lee Emanuel has arrived in Wellington and US stars Will Leer and Brandon Bethke join Team Willis on Monday.

The quartet will compete in the Cooks Classic in Whanganui next Friday as well as the International Track Meet on the grass track at Christchurch's Christ's College on February 4.

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