I sense more energy when I do the RTR than any other meditations, including yoga. The energy is hot and everywhere in my body.
Is this normal ? Am I helped by a god or is it my energy ?
Is the RTR more useful to advance than chakras meditation ?
Because for me it seems to be the case, some blocked energy is becoming unblocked.

rtrs seem to be more powerful than meditations, with them it is much easier to create courage to meditate

The RTR alone is NOT more useful to advance than chakra meditation. What you are experiencing is just the romval of dross and curses from your soul and is normal. Do not give up mediating on yourself.