My Pokémon's HP and CP increased, but unsure why (GO)?

Question

In Pokémon Go, Vaporeon increased from 84 HP to 101 and around 450 CP to 650. I used him at one friendly and capturing two enemy Gyms. Also I went up 2 or 3 levels starting around 12, but only the Pokés I fought most seem affected and only this one changed a lot. It attacked more gyms. Is that supposed to make them stronger???

Comments

I think your train your pokemon by fighting friendly gyms, not sure though

Answer 1

Did you power it up, if not it must have been from the friendly or enemy gyms. Hoped this helped.

Comments

Thank you.  Niantic does not explain the power up feature well and I thought it was a temporary change rather than permanent.  Thank you.

Answer 2

I put my Vaporeon on a gym last week and when I checked it after a couple of days, its CP had increased by 211. I didn't level up as a trainer while it was defending, but would have been unable to power it up myself anyway, as you can't do anything with your Pokemon while they're sitting on a gym.

I have only found a few posts from players about this happening. I know some Pokemon have had their CP boosted to balance things out etc., but I thought it meant the CP cap had been raised, not that they could be boosted just by sitting in your inventory or whilst defending a gym.

I have now further powered up my Vaporeon to 1904 and, according to the CP arc, there is still room to power up a little more when I get enough stardust. I took over a gym this morning and have placed my Vaporeon on it. I'm hoping more team members will place some strong Pokemon there too, so I can see if it happens again before getting kicked off.

Maybe it was a one-time boost to help with the balancing out issue? We'll see.