In 2009, Matt Cutts, an American engineer who works for Google, felt he was ''stuck in a rut'', so he set himself a 30-day challenge. He vowed to walk 10,000 steps every day for a month - and he accomplished it.
Three years later, he has transformed his life in one-month intervals doing things such as following a vegan diet, learning to play the ukulele, getting eight hours' sleep a night, and doing something nice for his wife every day. Recently, he underwent a 30-day technological detox, abstaining from reading news online or checking emails after 9pm.
He has even climbed Mount Kilimanjaro as part of a 30-day makeover.
On hearing about his mission, TED - the conference for leading world thinkers - invited Matt to speak at an event. His seminar has been watched online by more than 3.5 million people.
''It turns out, 30 days is just about the right amount of time to add a new habit or subtract one,'' Cutts says. ''I noticed, as I started to do harder challenges, that my self-confidence grew. I went from a desk-dwelling computer nerd to the kind of guy who bikes to work for fun.''
He also found the challenges made him live more in the moment.
''Instead of the months flying by forgotten, the time is much more memorable,'' Cutts says. ''I challenged myself to take a picture every day for a month and I can remember exactly where I was and what I was doing when I look at every photograph.''
He is not alone in his quest. In the past few years, the popularity of 30-day challenges has grown. Many yoga studios offer discounts if you clock up 30 classes in a row, and there are 30-day programs for meditating, quitting sugar and improving self-confidence.
In Ocsober, we're encouraged to give up alcohol, while Parched March urges us to drink more. In November, which is national novel-writing month, thousands of novice authors attempt to write a 50,000-word book in 30 consecutive days. Those who don't achieve it can practice self-acceptance during ''Grateful in April'', when participants are encouraged to count their blessings.
So, why is 30 such a magic number? If you believe in the theory of biorhythms, everyone's body clock has the same cycle of renewal. Our physical body works on a 23-day cycle, our emotional body on a 28-day cycle, and our intellectual body a 33-day cycle. This makes one month ideal for self-improvement, although it's worth noting that this ancient theory has no scientific proof. Many medical studies show that repetition is the key to making lasting changes.
''We can actually lay new neuron pathways in our brains by repeating an action or way of thinking,'' psychologist Meredith Fuller says. ''The aim is to transform a new activity into an automatic habit. With repetition, it becomes something we do without thinking; in fact, we experience discomfort if we don't do it.''
The odds for successful behaviour change are stacked in your favour when you undertake an organised challenge as part of a group.
''That sense of camaraderie is key,'' Fuller says. ''It heightens motivation and the resulting pride in your achievement. We respond well to cues - whether that's a gold star next to your name on a noticeboard or a hug from a friend after a workout. It's far harder to let someone else down than yourself.''
In March 2011, British web developer Michael Burton set himself a goal: to code a website from scratch in one month. The result, 30daychallenges.net, is a place for others to share their trials. It has 2500 members worldwide who track their progress on an online calendar, where others can write words of praise or encouragement.
''I wanted to find a way to better myself that didn't cost money,'' says Burton, who joins in members' challenges when they inspire him. ''That sense of victory is addictive. Some goals are fun, like reading 10 books in 30 days, but others, like giving up smoking, are truly life-changing.''
The majority of challenges featured are fitness-based. A recent study from the University of Michigan found that working out with a virtual partner is just as motivating as doing it with a real-life fitness buddy.
During a study, 200 participants were asked to hold a series of strength-building poses, such as the plank. First, they exercised alone and then, using a webcam, they competed with a virtual partner to see who could hold a pose longer. Performances improved, on average, by 24 per cent. This suggests that an online fitness community can be just as effective as a physical gym.
Originating in Minneapolis, 30 days of biking was launched in 2011, challenging cyclists around the world to pedal daily, whether 10 miles or 10 metres. Past participants have ranged from complete beginners to Tour de France winner Greg le Mond.
''The project is not elitist,'' founder Patrick Stephenson says. ''It is not a political statement against carbon emissions. We just want you to remember how it felt to ride around your neighbourhood as a kid - that happiness, freedom and independence.''
Though many training programs suggest rest days for muscle recovery, they're not in the policy of 30 days of cycling.
''For us, a rest day, at least during April, is pedaling for two minutes instead of 20,'' Stephenson says. ''It reminds you that cycling doesn't have to mean punishing yourself up a hill. You can take a leisurely journey for the sheer joy of it.''
Participants share their two-wheeled journeys on social media. Through the website, they can also print spoke cards that boast ''I made the 30-day pledge'' to attach to their wheels.
The message, as with many of these challenges, is ''We're all in this together'' - and that's not just in the sporting arena.
Sydney mum Andrea Zanetich launched her fashion blog, Fox in Flats, two years ago to combat the loneliness of parenthood. Offering tips for ''navigating motherhood in style'', Zanetich began setting her followers style dares, such as wearing red lipstick for a week, or sequins in the daytime.
''I was inspired by a book I found in my local library called The Autonymum,'' Zanetich says. ''It's about a group of female friends who feel stuck in a rut so they dare each other to step outside their comfort zone.'' The dares originally spanned seven days, but became so popular, Zanetich now runs 30-day versions. In Darecember, more than 10,000 outfit photos were posted on the blog's Instagram page.
''It's a fun and manageable way to put a little focus back on yourself, even in the midst of a busy life,'' Zanetich says. ''I get beautiful emails from women saying the dare has made them appreciate their own beauty by being 'forced' to take a picture of themselves.''
And to pay for all these new clothes and gym visits, why not undertake a financial detox?
Business adviser Wilson Lunar wrote the best-selling self-help guide Save $30,000 in 30 Days and insists that's all the time you need to get your budget in order.
''It's the simple things done consistently that make the biggest difference,'' Lunar says. Cutting small costs, such as buying a coffee, can add up to big savings.
''One of the reasons people yo-yo after a crash diet is because they've felt deprived,'' he says. ''Challenges are tough but you still need to enjoy them.''
Lunar suggests adding variety to the month by tackling a different area of your outgoings every week, such as utility bills and entertainment costs. ''Don't underestimate the power of the small things done repeatedly,'' he says.
And if you do miss a day, don't catastrophise it into a failure. A missed day doesn't mean you need to go back to day one.
And when the final deadline arrives, manage your expectations. Rather than telling yourself, ''I'll now follow this regime forever'', set small sub-goals, extending the plan by one month and then another.
Or, like Matt Cutts, you could leap between different challenges, tackling one area of your life at a time.
In Cutts' words, ''What are you waiting for? I guarantee you that the next 30 days will pass, whether you like it or not, so why not think about something you've always wanted to try and give it a shot.''
- Sydney Morning Herald
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