Raiden wasn't gonna let Toshi go with Ryuga. He would want to go down the floor instead.
When Toshi suggested that he and Ryuga would go down. Raiden, as expected, objected to that.
"No, if anyone is going down it would be me."
"Hold it down, Raiden. You aren't going anywhere. I can just do the job easily," Toshi wasn't backing off easily.
"No. Because I think I would do the job more efficiently."
"And, how is that?"
"I can run faster than you!"
Surprisingly, Raiden was really good at sports. While Toshi was the champion of sword techniques, you could say Raiden was kind of an all-rounder.
Trying to find something that would be of interest to him, he tried every single sport and became a really good athlete who could even surpass Toshi.
"You are not going in a marathon! It is a matter of stealth, Raiden." Toshi had a point, too.