It is part of a push to get 20,000 families to sign up for the Flora Family Marathon, which means that groups -- who can be families, friends or colleagues -- can split a 25.2 mile marathon between them, running as much or as little as they want.
The lets people sign up for the marathon and specify how they wish to allocate their miles between each member.
Families can download a personalised training plan for each person taking part, choose which celebrity family they wish to receive encouraging training messages from, and set up an online sponsorship page to allow them to raise money for one of the official charities.
The push is being backed by a media campaign, with activity in the national press, online, on radio, outdoor and in-store. This is designed to drive people to the website.
Warren Plaskett, brand manager for Flora, said: "2005 is the 10th year of the Flora brand's sponsorship of the London Marathon and to celebrate we're helping 20,000 families across the UK get fit and healthy."
The official charities are Save the Children, The Steve Redgrave Trust, Tommy's 北京赛车pk10, The Scottish Society for Autism, SHARP, Multiple Sclerosis Society Scotland and Maplewood School.
Kenzie, of Blazin' Squad, said: "We chose the Save the Children Fund as we were upset by the tsunami. We wanted to do something to help."
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