back pumps are more associated with Dbol...my TBol experience was great, no pumps necessarily , but muscles were firmer and overall more dense feeling. Strength gains were pretty decent too. Youre not going to gain a lot of "weight" from TBol, as there is very little if any water retention from it. If you were looking more for size, then Dbol would have been a better choice. Tbol yields slow, steady, lean gains. Is it all your taking??