Department of Education inspectors have rapped schools for cutting the amount of time that exam students spend in physical education (PE) classes.
The pressure for results, particularly in the Leaving Cert points race, has been blamed for a trend in schools to sacrifice sport for exam subjects.
The department says second-level students should spend two hours a week -- the equivalent of three class periods -- doing PE.
But according to the latest series of inspectors' reports, not one of four schools visited was meeting this requirement -- and some students were doing no PE classes at all.
The inspectors have exp-ressed concern at a time of rising levels of obesity in Ireland, with more than one in five children regarded as overweight or obese.
Inspectors say the "practice of reducing or withdrawing curricular time for certificate examination students may, inadvertently, create the perception amongst students that physical education and engagement in physical activity is a low priority".
Their comments, in a report on a girls' school, stress that physical activity is essential for this age group and gender "to develop positive attitudes and sustainable health-related lifestyle behaviours, especially at such an important stage in their development".
In visits to schools last year, the inspectors found:
Loreto Wexford said it could only meet the PE requirement "when the department provides the school and its 706 students with such basic facilities as an indoor sports hall, associated equipment, dressing rooms and shower facilities".
A report on obesity produced for the Department of Health and Children by the ESRI last year found that 90pc of post-primary students were not meeting the recommended minimum of 120 minutes of PE per week.