Matt Hemsley, from sustainable transport charity Sustrans ,says the the Assembly should make the introduction of more speed restrictions part of future policy.
"Slower speeds limits really encourage people to get out and walk and cycle, which is really good for their health" he says.
"Fast-moving traffic in communities really puts people off".
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Wales are through to the Rugby World Cup quarter-finals after Australia beat England at Twickenham last night.
The Conservative's annual conference is getting underway in Manchester, and talk has turned to next year's Welsh election.
A band of showery rain will push through overnight, but it will feel mild.