Consider StarCraft: Brood War, a legendary real-time strategy game. To be played well, it requires between 200-400 actions per minute (APM), with some players going even beyond 500 APM. Some games last for more than an hour. Players use both the mouse and the keyboard. There's always more to do than you can realistically do. You are always putting out fires, managing your economy, producing units, securing income, carrying multiple attacks at once, fighting tactical battles, and executing strategic goals. Yeah I'd call that a pretty active sitting :)