Organisers of the Tokyo Marathon will distribute surgical masks to runners and volunteers if they request them over concerns about the coronavirus.
According to a statement from the organisers, four "preventive safety measures against the coronavirus" will be taken during the event, which will be held on March 1, reports Xinhua news agency.
The masks will be on offer upon request at the Packet Pick-up and at the venue in the finish area on the race day.
Alcohol-based hand sanitisers and antibacterial wet-wipes will also be available at the relevant venues, it said.
There will be operational revisions of the aid stations, but it is not clear what revisions will be made.
The statement said that it is a "personal choice" for the registered runners to make, whether to participate in the event.
"Please pay careful attention to your own health," it read. "One each individual must consider carefully. We would like to request the cooperation from all participants to monitor the body temperature, and if you have fever or experiencing symptoms of respiratory illness, we advise you to refrain from participating in the event."
Tokyo Marathon organisers last week announced that runners living in China will automatically be entered into the 2021 race if they fail to take part in this year's competition.
Some 1,800 runners living in China registered for this year's race.