“My experience of running very, very large programmes is that a small percentage, usually less than 10 per cent of people that join, cheat,” he said. 

Details of the software that will be used to track a person’s activity are still being worked on, but are likely to include a QR code check-in system, he added.

“You would turn up [at a park run], you’d show your phone, which would have a QR code on it,” he said.

While it would not track a runner all the way around the 5k, “it will say you’ve turned up to run”, he added.

“And if you join Weight Watchers, you have to take your phone every week and get it scanned so we know you’re going,” Sir Keith said.

“It’s not rocket science, but the object of the exercise isn’t just join the programme and tell us you’ve lost 20lbs and you get rewarded, that’s not the way it’s going to work,” he said.

It could also be possible to validate a participant’s progress during the programme by working with pharmacies to install electronic scales inside stores to scan a person’s QR code and record their weight.

A user’s supermarket shop could also be tracked through the app by linking it to the retailer’s loyalty card scheme, Sir Keith explained.

Supermarkets ‘very willing’ to take part

A person’s supermarket shop could also be tracked through the app by linking it to the retailer’s loyalty card scheme, Sir Keith explained.

Discussions are ongoing with major supermarkets, but early indications showed they were “very willing” to take part, he said. 

Healthy food, including fruit and vegetables, in a person’s shop would earn them points and technology to track how many calories are in your basket could also be used. “If your calories next week are down, you could get rewarded for it,” Sir Keith said.

A company has now been awarded the contract to run the scheme but details of the firm are yet to be disclosed. It is understood a master contractor will oversee the project and outsource some elements to other companies. Sir Keith will stay on to advise the programme.

Rewards will be based on what incentivises people to stick to permanent healthy life choices and these could differ depending on geographic regions and even socio-economic status, Sir Keith said.

Rewards can be ‘effective in changing behaviour’

Asked if rewards such as energy, fuel or food vouchers could be offered through the scheme, he indicated they are a possibility.

The options available will be driven by public choice “providing the rewards are healthy”, he said. 

“The most important thing, and this is crucial, the reason these programs are successful, is they’re run digitally and you get to know what it is people really want,” he said.