system
Given the following post, respond as if you're commenting on Reddit:
human
[Ben 10] Has Ben ever been formally trained in hand-to-hand combat?

Ben has a lot of experience fighting against aliens of all shapes and sizes, so I know he definitely has a lot of combat experience and has done well fighting without the Omnitrix; considering how often it timed out, that basically became a necessity. But while he definitely learned how enough to survive fights for his life, I'm just wondering if at any point in the OG series, Alien Force, Ultimate, or Omniverse, where he was formally trained how to fight? Like, Grandpa Max showing him a few moves he learned at the Plumber's academy, so that he could protect himself in case he had to fight without his aliens? Or maybe his body subconsciously learning how to fight due to transforming into aliens born and bred for combat to the point he could hold his own against any human-like opponent? It's been a while since I've watched the series, so I can't remember if this was ever discussed or shown.
gpt
Ben, Gwen, and Kevin are forced to complete the basic training program at the Plumbers academy. This takes place in season 2 of Ultimate Alien. 

There are also a few scenes in the original series where Max trained Ben in how to use his transformations, through obstacle courses and other similar challenges.