SASUKE (サスケ) Stages
The 1ST Stage is designed to test a competitor's overall athletic ability. Over time repeat competitors condition themselves to pass the stage. Once that happens the Sasuke stage designers will overhaul some of the obstacles to make it more difficult.
One hundred participants are given the opportunity to attempt the First Stage, a course which primarily tests one's speed. The object is to hit the buzzer at the end of the course before the allotted time expires. If a competitor goes out of bounds or comes into contact with the water in any of the pits below the course, he is disqualified.
Typically, 85 to 90 of the 100 original entrants are eliminated in this stage. However, in the 4th competition, a record 37 of the original 100 competitors made it past the first stage. After the 4th, 17th, and 27th competition, the first stage was thoroughly redesigned to be much more difficult and prevent large numbers of people from moving on. In fact, a G4 special inside the making of the 18th Sasuke competition revealed that the redesign of the first stage for the 18th competition was done with the intention of seeing all 100 challengers fail it. This did not happen, however, and that has only spurred the production team on to make this and all stages to follow even harder.
That goal was almost met in the 19th competition, where much to everyone's surprise, only two competitors cleared the first stage (neither of the two being Sasuke All-Stars), a record in Sasuke history. (The only time something similar has happened was in the first Kunoichi, where again, only two competitors cleared the first stage.) Executive producer Ushio Higuchi said in interviews later that even he was surprised at the results, anticipating that around 10 to 12 people would survive in spite of the production team's attempts at making the first stage unbeatable.