After two months and 1600km on foot between Waiheke Island and Queenstown, he reckons he has found it.
What does a 41-year-old real estate company owner do when he feels overweight and in need of a recharge?
Walk between his two favourite places in New Zealand - Oneroa, where he lives and works, and Queenstown, where he lived for two years nearly 20 years ago.
Celebrating his arrival in the resort yesterday with a meal and Champagne were his partner Lucila, family and friends.
A little humble pie may also have been on the menu after some tried to talk him out of the journey.
''They all thought I was completely mad, and some were quite fearful of my safety,'' Mr Smith said.
''I wanted to lose weight and I wanted to walk to Queenstown, but the ultimate goal was to give myself a better lifestyle - to get my body and mind in a state where I can live my life to the maximum.''
He endured blisters, intense pain from an old heel injury and the fatigue of long days on the road - the longest a 78km, 19-hour stretch through Marlborough.
He was also reminded of the beauty of New Zealand's landscape, touched by the generosity of strangers who made sure of his next bed and meal, and sampled some of the best food and wine the country could offer.
''When you're averaging 50km a day, you can pretty much drink as much as you like.
''I wanted instant gratification and to enjoy the experience, rather than just a hard slog.
''I've realised something they don't teach you when you're young, and that's how incredibly adaptable your body is.
''It'll become a fat and lazy thing if you don't do anything with it, but it becomes fit, agile and strong if it needs to be.''
Throughout the walk he continued working, keeping in touch with his staff by smartphone - connected to Bluetooth-compatible headphones equipped with a microphone.
''I've done a massive amount of work - the guys in Waiheke have never found me to be so accessible.''
The experience had given the Ray White principal owner ideas on better ways to run his business.
Four months ago, before changing his diet to prepare for the walk, he weighed 94kg.
Now he weighed 71kg.
One of the first things he would do upon getting home was order an expensive, tailored suit that wouldn't lie if he began putting on weight.
''That will be my benchmark.''