Japan’s Nao Kodaira won the 500m title on the first day of the ISU Speed Skating World Cup in Nagano ©ISU

Japan's Nao Kodaira and Yuma Murakami made the ideal starts to their home Speed Skating World Cup in Nagano, opening with wins in the 500 metres.

As 33-year-old reigning Olympic 500m champion and double World Sprint Championships gold medallist, Kodaira endured mixed fortunes over her specialist distance in the three previous International Skating Union World Cups of the season.

There were also high hopes for home prospects next year in the men's 500m, as Murakami won from team mate Tatsuya Shinhama.

Kodaira's 23-race-winning run ended at the opening World Cup in Minsk, and although she won the second race, she was only third in Nur-Sultan last weekend.

But a time of 37.49sec earned her victory in the arena that hosted the 1998 Winter Games ns allowed Kodaira to take the lead in the overall World Cup ranking from Olga Fatkulina of Russia, who finished fifth this time around in 37.77.

Another Russian, Angelina Golikova, was second.

"The first 100 metres were way better than last week," Kodaira said, referring to a mis-stroke at the start in Kazakhstan.

"But my full lap was not as good.

"I could not really keep the pressure on my skates."

She finished far behind her own 2017 track record of 37.13, although will get another chance to set the pace in the second 500m on Sunday.

With an overall time of 34.58sec, Murakami was was 0.02sec faster than the 2017 track record set by compatriot Tsubasa Haseqawa.

Home athlete Yuma Murakami won the men's 500m as the ISU Speed Skating World Cup in Nagano got underway ©ISU
Home athlete Yuma Murakami won the men's 500m as the ISU Speed Skating World Cup in Nagano got underway ©ISU

Shinhama took silver with 34.57, ahead of Russia's Pavel Kulizhnikov, who claimed bronze in his first World Cup of the season after returning from injury.

Kulizhnikov rounded off his opening evening by helping Russia win the men's team sprint, ahead of Japan and Canada.

Earlier, Canada's Jordan Belchos won the mass start men's race, ahead of Joey Mantia of the United States and Belgium's Bert Swings.

Ivanie Blondin of Canada earned her fourth World Cup gold in little more than a week, after winning a mass start ladies race that was even more chaotic than usual given, that the lack of semi-finals meant 24 starters.

Japan's Olympic champion Nana Takagi had to settle for silver ahead of Mia Kilburg-Manganello.

Blondin arrived in the Japanese city having won gold medals in the 5,000m and the 1,500m in the Kazakh capital on the previous Sunday.

Meanwhile, in the team sprint ladies event the Dutch were victorious ahead of Russia and Japan.

Competition in Nagano concludes on Sunday.