Cooling energy?

Hello,
Wasn't sure the best way to phrase the topic title. I was wondering if anyone here has similar experience and/or could provide a bit more information.

I have a disability, and during a training session last week I was told not to think about being violent when training/sparring because the heat energy coming from these thoughts and/or actions could put pressure onto or damage my spine.

I was instead told to come from a pacifist sort of angle, which would use cooling energy.

Again, I wasn't sure how to phrase this without it sounding weird. The idea sounded reasonable enough to me, so I was just wondering is there anything that I can do to better develop this mindset? I try not to think violently anyway, but having been made aware of this, it's something that I've been thinking a lot of.

By the way, the individual that informed me of this is not always present at training sessions so it will be a while before I can speak to him about it in more detail.

Thanks.