I just wrote an article on this topic. Just like NSAIDS can negate the inflammation response from training, fish oil can act in a similar fashion. It will lower arachidonic acid formation which ultimately blocks PGF2a which has demonstrated to elicit protein synthesis and initiate growth factors in repsonse to training. However, fish oil is amazing in lowering total triglycerides, blood pressure, and has been proven to help body fat loss. It also has a protein sparing, anti-catabolic effect. I have experimented with 48 fish oil caps a day plus 4 tbs of olive oil and it was too much. I was flat and my blood was way too thin. However, if dosed at around 12-15 caps a day it will aid in body composition change, decrease propensity for fat accumulation when bulking and help joints that are usually problematic. Fish oil is great, too much is bad. Like anything in life.