Jeffrey Leeke takes his eight-year-old granddaughter to gymnastics once a week and said each afternoon, hundreds of children, parents and carers had to get across Stockland Drive at Glendale without traffic calming measures in place.

"Recently they've blocked off all the car parking and it forces parents and carers to park in the shopping centre and walk across Stockland Drive, and at that particular point there are four lanes of traffic and two bus lane parking bays.

"Parents are effectively trying to take little kids from age six upwards across four lanes of traffic and there's no traffic calming measures between two roundabouts," Mr Leeke said.

"When the kids leave it's quite intense, you've got a changeover of 80 to 100 kids coming in and out and there's no pedestrian crossing or single-lane traffic."

The car park on the same side of the road as the centre has been closed while construction is under way on its $52 million expansion.

The project will ultimately include the new NSW Trampoline Centre of Excellence, an athlete testing centre, a sport and community centre, a gym and a larger car park.

Mr Leeke said he was told something would be done down the track, but he argued that something needed to be done now.

"This is going to be very interesting when we go to an inquiry if someone's hit, we talk about black spots and you've created one," he said.

"I'm a bit over it, you get to the point where it's like, 'I've raised it, you're not answering, I'm going to elevate it' because the court of public opinion is greater than any one person yelling in the wind'.

"Worst comes to worst, heaven forbid there was a coronial inquest, they'd love to see the video, they'd love to see the email trail and go, 'Well it's on you guys, you're now responsible, you've done nothing'."

A Lake Macquarie council spokesman said it had received a request about the issue this week.

"Hunter Sports Centre users were provided with more than one month's notice of the impending closure," he said.

"The road is already signposted as 40kmh, designed to create a shared pedestrian and vehicle environment.

"We have asked NSW Police to increase enforcement in this location to ensure road users are adhering to the speed limit."

He said existing pedestrian paths remained open and led to refuge islands, and the nearby roundabout "also reduces vehicle speeds in both directions".

The spokesman said work would begin next week on installing a signalised pedestrian crossing about 50 metres west of the current Hunter Sports Centre entry.

"Traffic management will be in place during installation, with some lanes of traffic closed during this period," he said.

Mr Leeke said he was concerned that some older teenagers were crossing the road by themselves, along with elderly grandparents who weren't as mobile.

"They [construction workers] said a pedestrian crossing would be put down near the roundabouts but that's still hundreds of metres away from where people have to cross the road and people will take the path of least resistance every time," he said.

"I was in the military for 34 years, and so I look at things from a safety perspective and this just ain't safe, we're getting away with it until something goes wrong."

The car park is expected to remain closed for the next four to five months while work is under way, the council says.