It's that kind of reaction inside a beardie's body that fuels their fires too, except that there are no broken blood vessels, it's all done with thermal receptor cells. It's more than just blood that causes the heat from sunburn, as that goes much higher than a human's core body temp, anyhow. The cells are actually excited by stored radiation that gets trapped in the blood and all the movement from that energy creates heat.
Thermal heat is blocked from deep tissue absorption because fat, skin, muscle, etc. all absorb and dissipate it. Radiant energy penetrates right to the bone where it does the most good.
The Zombie Mama is here!