There must be a dramatic improvement in the quality of PE in primary schools, according to a major report from the Scottish Parliament's health and sport committee.
The report also bemoans a scarcity of innovation in secondary PE and school facilities being closed off to the public.
The committee's inquiry into support for community sport has received considerable attention for predicting that the legacy of Glasgow's 2014 Commonwealth Games may be undermined by a lack of facilities, coaches and volunteers, but there is also concern around schools.
The "variation" in physical education skills among primary teachers causes concern. Although many primary teachers embrace PE and teach it to the same standard as other subjects, others lag some way behind. The committee also notes that it is rare to find PE specialists or peripatetic PE support in primaries.
MSPs add that it is "unacceptable" that 25 per cent of children leave primary school unable to swim; research suggests the figure may be even higher in poor areas.
The "best value and most realistic" way to improve primary teachers' PE skills is through CPD, and progress has already been made following the committee's earlier Pathways into Sport inquiry, says the report.
But another idea, providing more specialist PE teachers in primaries, has been hamstrung because "for the foreseeable future there will be insufficient resources".
The committee is concerned by evidence that disengagement from sport at school age "could be for life", although it acknowledges that the drop-off in physical activity in adolescence is attributable to societal factors and has "little to do with the ways in which physical education is provided in secondary schools".
There are many cases of collaborative work between PE teachers, Active Schools coordinators and young volunteers - St Maurice's High in Cumbernauld, North Lanarkshire, is highlighted - but "progress in this type of innovation is patchy" and some areas are not trying hard enough.
Stirling is praised for having made links across schools and communities, so that people "emerged from their silos and actively collaborated with each other" - but, again, not enough areas are making such an effort.
The committee is concerned about outstanding sports facilities in schools being closed to the public.
There are a range of reasons, including contractual issues and cost, but the committee also points to evidence of a "lack of commitment" among school management and headteachers.
- Scottish Rugby partly attributed a loss of sporting culture in Scotland to "the decline of sport in schools".
- Commonwealth Games and sport minister Shona Robison said it did not always take a lot of money to make school facilities more accessible - it could be as straightforward as having separate doors for the community and for pupils and teachers.
- Services should be seen as the problem, not the teenage girls who use them, when addressing plummeting physical activity rates in adolescence, according to sportscotland.