European sports ministers have pledged to improve the status and training of PE teachers and investigate claims that the subject is being squeezed out in many countries, including the UK.
Rising numbers of children suffering from obesity, diabetes, high blood pressure and other problems associated with a "couch potato" lifestyle are being reported across the developed world.
The issue dominated the 16th Informal Meeting of European Sports Ministers, a gathering of ministers, civil servants and pressure groups from 42 countries. It was organised by the Council of Europe and held last week in the Polish capital, Warsaw.
Delegates demanded action to tackle the problems caused by youngsters spending their free time in front of computer or TV screens.
Recent international surveys have shown academic subjects and cuts are squeezing out PE and sport.
In some European countries PE teachers are not just poorly regarded but are paid less than colleagues with equivalent experience in other subjects.
Maud De Boer-Buquicchio, deputy secretary general of the Council of Europe, said: "A century ago in Europe it would have been difficult not to have sufficient exercise. Today, human power has been replaced by machine power and artificial intelligence. The move towards a sedentary lifestyle is accelerating rapidly.
"Such conditions as obesity, diabetes mellitus and high blood pressure have never been seen in so many children and young people at such a young age. This will have very serious consequences in the future if urgent action is not taken."
An undertaking to increase the amount of time set aside for PE to three hours a week across Europe was dropped from the conference resolutions amid fears that the target was unrealistic.
A survey by the Council of Europe's Committee for the Development of Sport, which drew responses from 33 countries, shows that primary schools teach PE for an average of 121 minutes a week and secondary schools for 117 minutes.
However, in around a third of the countries surveyed just 90 minutes a week are set aside for teaching PE in both primary and secondary schools, half of the proposed target that was dropped from the meeting's final conclusions.
The UK failed to respond to the survey but children in England and Wales have an entitlement to two hours of physical exercise a week, though this can include extra-curricular sport and, in reality, some schools timetable just one PE lesson a week.