It's Tokyo's turn to prepare for the 2020 Olympic Games now that the Rio Olympics are history and organizers are hoping the event will help boost the country's economy.

Economists estimate that the advanced countries that have hosted the Olympics have realized about a 0.3 percent increase in annual economic growth during the years needed to prepare for the Games. Experts says that will translate into about 20 trillion yen for Japan's economy.

"The economic benefit of the Tokyo Olympics will be shown in two sides: one is the economic growth brought by infrastructure construction; and the second is that with the upcoming Olympics, tourists will increase, which will also boost the economy," said  Toshihiro Nagaham, chief economist of Dai-Ichi Life Insurance Research Institute.

However, a labor shortage will be a major challenge for Japan's Olympic preparations. That's because Japan is busy rebuilding areas ravaged by earthquakes in an effort that requires a significant work force.

"Although there's more need of construction, workers in the sector are decreasing. How to solve the shortage of labor is a main issue. On the other hand, with increasing demand of construction, material prices have surged. How to control the construction expenses is closely related to the country's future loans and fiscal problems," said Toshihiro Nagaham.

Winning 20 to 33 gold medals at the 2020 Olympics will be a major goal for Japan but a boost to the country's economy through more construction and increased tourism is what organizers see as the real prize.