More that speak to this
The spine
It was like this raging fire
The power of loving-kindness.
What Scott says
it was like this raging fire and i would just sweat did loving kindness practice every day for 30 minutes for about six months you know maybe five days a week six days a week but almost every day and over time what happened is it began as the first two months i felt nothing i guess longer than six months probably for a year or longer but um and then after a few months i felt felt this subtle warmth in my chest very very slight and then after four or five months it was like this raging fire and i would just sweat as i was doing the loving kindness practice almost like a if you're familiar with tibetan like a good tummo practice