Chuck (Japanese: シジマ Shijima) is the Gym Leader of Cianwood City's Gym, officially known as the Cianwood Gym. His specialty is Fighting-type Pokémon. Chuck gives out the Storm Badge to Trainers who beat him.
Chuck made his only anime appearance in Machoke, Machoke Man!. Ash and his friends met a man roughhousing with a Machoke. After following him, Ash discovered that the man was Chuck, Gym Leader of the Cianwood Gym. Even though he is the Fighting master, he gets tired easily due to his body shape. His wife continually makes fun of him because of this. He is positive-minded and emotional and has a tendency to break out into tears if happy. His battle technique is to battle with his Pokémon to improve their concentration.
Later, Chuck and Ash had their battle for a Storm Badge. Ash used Pikachu who got defeated by Chuck's Poliwrath. Ash then used Bayleef who defeated both Poliwrath and Machoke.
It was later revealed that Brawly, the Dewford Town Gym Leader, used to be one of the many students of Chuck.
He reappeared in flashbacks in Why? Wynaut!, Brave the Wave and Wheel of Frontier.
- His Japanese Leader title is 唸る拳で語る男.
- Chuck appears as an opponent in Pokémon Puzzle Challenge. He uses a Primeape to battle.
- In Generation II, both Chuck and Pryce's weakest Pokémon are at the same level, level 27.
- In Generation IV, Chuck will appear in two places: Cianwood Gym and Fighting Dojo at the same time, when the player calls him for rematch on Wednesday night.
- Chuck has an illegal Sandslash in Round 2 of Pokémon Stadium 2: Metal Claw is an Egg move in Pokémon Crystal, while Rock Slide is aGeneration I TM.