SINGAPORE - Lose weight and win cash.
While inducements are known to yield results, studies have also shown that it is hard for people not to regain the kilos shed.
A study by the Duke-NUS Graduate Medical School and Singapore General Hospital (SGH) now wants to find out what can be done to get people to maintain their weight loss and activity over a longer period.
In the first study of its kind here, participants can opt to get $20 a month or a one-in-10 chance to win $200 a month, when monthly weight-loss and exercise targets are met.
The study, which began last October and will end in March 2015, aims to recruit more than 180 participants. They must be aged between 21 and 65 and have a body mass index of between 25 and 40.
They must pay $234 for an obesity-management programme and $165 to enrol in the incentive scheme.
During the four-month obesity-management programme, they get supervised gym sessions, a pedometer to track the number of steps they take and advice from SGH's Lifestyle Improvement and Fitness Enhancement centre.
All participants go through this programme and will have their weight and activity monitored for 12 months in all.
Those not assigned to the incentive scheme from the start will form the control group and get their $165 refunded.
The incentive group will get to choose guaranteed payments or lottery-style chances of winning cash for losing 1kg or more a month and taking 10,000 steps a day for 20 days of each month.
These payments are available for eight months but stop in the final four months.
In the eighth month of the study, the control group will also get a payment equal to the average paid to incentive-group participants. The amount they get is unrelated to the weight they lose.
The study, funded by the NUS Initiative to Improve Health in Asia and Duke-NUS, is expected to cost up to $171,000.
Asked if employers or policymakers who want to implement such schemes should keep paying out cash if the rewards work, Duke-NUS health economist Eric Finkelstein, one of the study's lead researchers, said he is not against such a move.
The cost of doing so may well work out to be lower and the results more effective compared to other expensive health schemes with higher dropout and lower success rates, he said.
Marketing lecturer Ho Teck Hua of the NUS and University of California, Berkeley said it is still unclear whether it is possible to get people to lose weight permanently via cash incentives.
Mr Jonathan Chew, founder of the Absolute Living workplace-health group, said the competition to win something in a lucky draw can be a good incentive. "The month monetary incentive can also work but it also depends on how it is marketed," he said.
Trainer Jeremy Ko, who owns the Movement First fitness equipment store, pointed out that guilt and commitment can also nudge people into working out.
"If you've made an appointment with a trainer, you are more likely to keep to your regimen than if you work on your own."
Those trying to stay fit have mixed views about whether money will prod them to exercise more.
Mr Teo Leng Kee, 26, a student, said he would force himself to do it for $2,000 but "if you motivate me with money and you cut it off later, I won't continue".
Project manager Cheow Xinyi, 28, who wants to shed 8kg, said: "If I'm motivated enough to go for a weight-loss programme, I'd want to make it work, so getting cash is secondary. But the lottery might be more attractive - $200 is a sizeable amount."
Those interested in the study can e-mail email@example.com for more details.
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