Palmerston North's Arapuke Bike Park and the Gordon Kear Forest are now closed for public use.
Signage is installed that the reserves are closed and vehicle access is also closed.
All of the city's other parks and reserves remain open, but the use of playground equipment is not allowed.
The Palmerston North City Council's Emergency Operations Centre controller Tom Williams says the council knows how popular the two sites are with the community in normal circumstances but the decision was made following national guidelines and the Department of Conservation's decision to close its parks.
"If these two reserves remained open, we would be unable to control how many people used them," Williams said.
"We're also supporting the central Government's call for people to 'stay at home'."
Williams said another factor in the decision was the district health board's recommendation that people don't undertake "extreme" physical activity or sport. This is to prevent injuries and accidents that could lead to further pressure on medical facilities and more risk to those working for emergency services.
"We have some great parks and reserves in our city that are still open for exercise for walking and jogging – but people need to take the advice of national leaders who are encouraging people to not undertake activities that present potential risks of injuries."
Williams added that this decision would be disappointing for regular users of the reserves, but the council wants to do all it can to stop the spread of Covid-19 and keep people safe during this national isolation period.