The 20th Choujin Olympics Arc is the second story arc of Kinnikuman. It features the very first Tournament Arc of the series. It's length is Chapters 28-51.
Due to Ultraman withdrawing, Kinnikuman is selected (By default) to represent Japan for the 20th Choujin Olympics, a competition for superhumans from across the world. And he'll have his work cut out for him, as not only will he be up against his friend Terryman, but some very brutal Choujin! And of course, Kinkotsuman is always lurking in the shadows, planning to cause trouble...
- Bring My Brown Pants: Kinnikuman is saved from Ramenman's Camel Clutch hold when Ramenman realizes that Kin pooped in his pants, and lets go in disgust.
- Family-Unfriendly Violence: In-universe! Meat realizes that the second half of the quarterfinals are being broadcasted by radio is because Ramenman, Brockenman, and Curry Cook are brutal choujin who kill their opponents in ways that can't be aired on TV. To prove it, Ramenman rips Brockenman in half!
- Heroic Second Wind:
- Terryman gets one during his match against Skyman.
- And of course, Kinnikuman during his match against Robin Mask.
- Let's Get Dangerous!: After goofing around the entire Olympics, Kinnikuman finally sobers up for his match with Robin Mask after Ramenman gives a heartfelt plea to Kin, if only so he can look at his own defeat with pride.
- My God, What Have I Done?: When Robin Mask thinks he's killed Kinnikuman, he realizes that he was taking the match to seriously.
- RockPaperScissors: The first preliminary. Naturally, everyone is irate at having to do something so mundane is part of the Choujin Olympics. Kinnikuman wins by choosing Kani Besu as his opponent, as the crab choujin's claws are permanently stuck on "scissors".
- Taking the Bullet: When Kinkotsuman tries to shoot Kinnikuman after the match with Ramenman, Terry blocks the shot with his own body. He survives, but now his leg is wounded before his match against Robin Mask.
- Wins by Doing Absolutely Nothing: a battle royal is held to see who makes it to the quarterfinals. Even though Kinnikuman was defeated instantly, he still passes because the other fighters killed themselves duking it out.