This is the first obstacle in SASUKE that allows the competitors to touch the water to progress, as usually, touching the water in any fashion results in disqualification.
The obstacle is a large swimming tank, 10m in length and 2m in depth, in which the competitors must swim through the tank to reach a ladder and move on to the next obstacle. There is also a series of jets toward the end of the obstacle, designed to disrupt their progress to the ladder.
Because of this obstacle, at the Second Stage's starting line, every competitor who advanced to the Second Stage must wear swimming goggles on his/her head, and use them while attempting this obstacle.
Although all competitors to attempt the obstacle cleared it in SASUKE 28, it helped slow down Matachi Ryo enough to time out at the Passing Wall. During Asa Kazuma's run in SASUKE 28, there was a platform placed after the Backstream, but this was later removed in the next runs.
In SASUKE 29 the jets were more powerful, resulting in the biggest pressure for the competitors. The jets were later reduced after Hashimoto Koji's run and increased after Takahashi Kenji's run. However, the obstacle was still deadly, as 11 out of the 21 who attempted the Second Stage failed there, including 5 former finalists (Okuyama Yoshiyuki, Hashimoto Koji, Urushihara Yuuji, Matachi Ryo, and Yamamoto Shingo), while it slowed a further two finalists (Lee En-Chih and Nagasaki Shunsuke) to the point where they timed out on the Passing Wall.
In SASUKE 30, the jets' speed were reduced. As the result, less competitos failed there. However, it did cause Yamamoto Shingo to swim to the side of the pool (as the result of inhaling some water) and it also slowed Urushihara Yuuji and Morimoto Yūsuke to time out on the Wall Lifting.
In SASUKE 32, the length of the obstacle was reduced from 10m to 9m.
Competitors' Success Rate
- All results based on the TBS broadcast and external information found