Only a third of pupils play sport outside school, said a survey

The survey of 1,000 people also discovered youngsters played outside for just one hour on average each night and watched more than three hours of TV a day.

Two out of three parents questioned said they were concerned about their child's weight.

The fitness camps - due to be launched by the website sportsfundays.com this weekend - aim to turn youngsters "from couch potatoes into runner beans".

Its organisers have accused the city council of cutting funding for children's sport.

The local authority has slashed funding available for outdoor activity Steve Flanagan, sportsfundays.com

Youngsters aged four to 16 will be offered courses in tennis, hockey, football and "gladiator skills".

Steve Flanagan, of sportsfundays.com, said: "We set up sportsfundays.com due to the increasingly apathetic interest in sport and the lack of activities provided for children during the school holidays.

"The local authority has slashed funding available for outdoor activity and we believe that we are in real danger of creating a generation that has missed out on the vital skills that sport brings."

However, a Manchester City Council spokesman denied it had "slashed" children's sport budgets.

'Free sessions'

He said a wide range of sports and leisure activities for young people were being provided over the summer holidays.

These included a programme of sports, craft and environmental activities in parks across the city from July 28 until September 7.

He added: "These sessions are free of charge and aimed at boys and girls aged 7-14 years.

"They include football, rounders, cricket, treasure hunts, athletics, basketball, parachute games, health walks, orienteering, junior bowls, pond-dipping, fishing, habitat creation and more."