Play England assistant director Catherine Prisk told parks managers: "Everyone involved needs to understand why it is valuable to have children using parks and open spaces and not just stuck in a corner somewhere."
Prisk was speaking at the GreenSpace conference Parks for Play, held in Sheffield on 21 April.
She outlined the Government's play strategy, which includes £235m to create spaces in every local authority. "It is a very exciting time," she added.
Mile End park director Mike Rowan said parks staff needed a greater focus on play.
"Many parks people have probably taken their eyes off the ball but the fact that money is available means there is a focus there again that needs be met," he said.