Shijima

Anime: 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 as he is a little fat. 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 Poliwrath and Machoke.

It was later revealed that Brawly, the Dewford Town Gym Leader, used to be one of the many students of Chuck.

Manga: Chuck taught Blue martial arts and how to train Pokémon when the boy was very young.

He initially was training for a battle with Wayne in his first appearance. He then noticed something amiss when he found his sandbags and Wayne's jacket slashed, but then he met Suicune, and with help from Wayne. He figured out that it was the cause of the jacket and sandbags and attempted to catch it with Wayne, but to no avail as previous Gym Leaders such as Clair had tried to do.

(Source: bulbapedia)