Gung-ho (adjective)

1. Overly enthusiastic and eager to participate, especially in a militaristic or aggressive way.
2. Extremely zealous and eager to get involved in something.

Origin:

From chinese "gōng hé" (work together), which was adopted by american marines as a motto during world war ii.

Examples:

1. He was gung-ho about joining the army.
2. The sales team was gung-ho about their new strategy.
3. He was always gung-ho about any new project.
4. He was gung-ho about the new product launch.
5. She was gung-ho about the new workout plan.