Leading article: So will they really take the plunge?

Free swimming for all was probably not the first thing that flabby Britons thought of when they considered the legacy of the London Olympics. Gleaming new sports facilities, tracts of much-needed housing and a landscaped park with boating lake were probably more like it.

That free swimming was not the most obvious by-product of 2012, however, does not make it a bad idea. In fact, it is one of those practical initiatives that pleases because of its simplicity. Fees for local authority swimming pools have risen and risen in recent years. While still relatively affordable compared with many other leisure pursuits, a swim at the local pool would probably attract more people if payment were waived completely. At a time when obesity threatens to become the new public health scourge, anything that spurs people to take more exercise is to be encouraged.

To start with, free passes for the over-60s are also a good idea. Swimming is especially good for those whose bones are beginning to creak and for whom more active pastimes are a distant memory. Aerobics or other exercise classes have been among the few leisure activities tailored to older people.

A cold shower of realism is in order, however, before anyone prepares to take the plunge. In this country we have disgracefully few public pools compared with our near continental neighbours. Many of the pools that do exist have badly outdated facilities or have been fully or partly privatised, with entry fees to match.

Where pools are still run by the local authority, it is not necessarily money that discourages people from using them. Hygiene is not always what it should be. Because there are so few of them, pools are often crowded and rules about running, diving and general rowdiness are ignored. If older people are to enjoy their swim, they might benefit as much from their own sessions as from a free pool pass. As indeed, would disabled people.

We also admit to a little wariness about showy initiatives such as this. The Labour government came in promising to end sales of school playing fields and reintroduce more sports into the curriculum. Eleven years later, playing fields are still being built on and many pupils have no more than one gym or sports session a week. We are all in favour of free swimming, but one reason it is needed is that so many other good intentions have remained just that.