Megan Harvey used to arrive at the office angry, and the reason why wouldn't surprise most Auckland commuters.
She was among those motorway slaves now spending an average 85 hours of their year in traffic, and it got to the point where the daily crawl was "driving me crazy".
So she went and did what a rising number of Aucklanders are doing: she began commuting on two wheels instead of four.
The trip from her Te Atatu South home to work at Auckland Museum, alongside the Northwestern Motorway, takes an easy 40 minutes on her e-bike.
As long as she leaves by 7.50am, rain or shine, she always knows she can get to work on time: there's no risk of a crash or a breakdown creating a delaying snarl-up.
It's also been better for her health - and better for the planet.
"Going back to my little petrol-powered hatchback is not something I can see myself doing."
They're all points that come through strongly in a new University of Auckland study that set out to understand why e-bicycle users tend to be generally happier than their car-bound counterparts.
Environmental sociologist Dr Kirsty Wild said it was often said that Aucklanders love cars – yet that wasn't something she'd heard from cyclists who had switched to an e-bike because they were desperate to get off congested motorways.
She was surprised to discover that, despite that congestion was growing worse, no data was being collected on what that meant for commuters' happiness or quality of life.
Overseas studies had shown how people who drove consistently were the most stressed out, those who walked found it relaxing, those who took buses and trains were often bored, and cyclists most likely found their commute exciting.
"Active transport users, and cyclists in particular, are consistently shown to be the happiest commuters, but there actually hasn't been much research exploring why," Wild said.
"So I decided to use our local research with e-cyclists to have a go at teasing out why cycling to work might be a good way of boosting your happiness."
Her study, which surveyed one group of e-bike users and another group that trialled them, turned up four reasons why making the switch made them happier.
Like Harvey, they felt more control of their lives by being able to predict arrival time – and the moderate exercise that came with e-cycling happened to be the best intensity for boosting mood.
Thirdly, there was a positive "sensory input" from spending more time outdoors – and fourthly, it meant more social interaction.
"People who walk and cycle tend to get the chance to see a bit more of what is going on in their neighbourhood, to start to recognise familiar faces, and to get more opportunities to make eye contact and to chat to people on their way in to work," Wild said.
"We found that these four themes are also pretty common in other overseas studies on cycling experience, but that no one has pulled them all together before to look at the reasons for high commute satisfaction amongst cyclists."
At the same time, she said the findings highlighted the negative impact that our lengthening, increasingly congested car commutes could have on our lives – and how it was likely that car users had resigned themselves to the fact that commuting was naturally stressful and awful.
"But I think the e-bikers provided some good examples of why commuting doesn't necessarily need to be one of the most awful parts of our day, and in that fact getting to work could actually be one of the most enjoyable parts of our day if we design transport systems that support active commuting a bit more."
Bike Auckland chair Barb Cuthbert said annual cycling growth across the city was up 8.9 per cent and rising, with midwinter numbers outstripping last year's summer highs.
"What's striking - but not surprising - is that the growth is highest on protected and connected routes, and on weekdays," she said
"It's proof that more and more Aucklanders are using bikes as an everyday transport option – and that good infrastructure is the key.
"Besides, you know which country officially has the happiest drivers in the world? The Netherlands, for all the same reasons it's a great place to bike.
"When everyone can get where they're going smoothly and safely, you increase the sum total of happiness on your streets. Who doesn't want that?"
The new findings follow an Otago University study that suggested swapping short car trips for walking or biking could achieve as much health gain as ongoing tobacco tax increases.
KIWIS AND CARS
• Data suggests that nearly 80 per cent of our trips are made by car
• 56 per cent of car trips are under 5km (12 per cent are under 1km).
• New Zealand has among the highest car ownership rates in the world.
• 17.3 per cent of gross greenhouse gas emissions are related to road transport.
• Only half of adults meet the national physical activity recommendations.