
On the first day, an opening ceremony was held on the facility's open platform.
Organizing Committee Secretary General Toshiro Muto explained the name "Let's 55" as the sum of the 33 Olympic sports and 22 Paralympic sports, multiplied by "Let's go." "Stock prices have been somewhat sluggish lately, but I hope this event can contribute even a little. Please enjoy the event by trying out the sports with the athletes who have come to the venue. And let's build excitement for the Games, now just 482 days away."
Koji Nagai, Group CEO of the company, stated, "This is the first time I've heard children's voices so full of joy at a stock exchange. I'm delighted we could co-host our first sports event with the Organizing Committee here. Athletes benefit from participating in three or more sports. While Japanese people tend to focus on one thing, I hope they experience many events here."
On stage, watched by Olympians participating in the event—Tsuguharu Ogihara, Kumi Nakata, and Hidehiko Yoshida—alongside current BMX cyclists and sitting volleyball players, Secretary General Muto and CEO Nagai each rang the stock exchange's symbolic bell once. This bell is typically rung to wish prosperity upon companies going public. They rang it to pray for the Games' success and economic development.
During the ceremony, 72 illustrations were unveiled: 49 featuring the Olympic mascot Miraitowa in athletic poses and 23 featuring the Paralympic mascot Someity in athletic poses.
The event featured experience booths for seven Olympic sports and five Paralympic sports, as well as partner PR corners. It also included talk shows and lectures by athletes, plus a classical concert, drawing large crowds of families on both days.