well I just finished a 5 week SD cycle and I lifted heavy (squats, deads, cleans, etc.) throughout most of the cycle. My extreme lower back feels like it has been injured so i take a week or so off from hitting it and it feels fine. I do heavy t-bar rows and it hurts again..bad! I ahd to get icyhot back pads on it for like 8 hours just to feel mobile. this pain goes away after a day or so and i feel 100% okay and have full flexibility and range of motion pain free. It feels simila to the SD lower back pumps.....what is the typical duration/intensity of these back pumps?