The authors sought to evaluate the effects of physical training and supplementation with shark liver oil on the onset of cachexia syndrome. The association of both treatments in relation to tumour mass. Non-tumour bearing individuals, physical exercise and shark liver oil supplementation and their effects on the immune system. Supplementation with shark liver oil and physical exercise alone on the proliferation of defence cells. The results corroborate the hypothesis that physical exercise and supplementation with shark liver oil play an important role in the treatment of individuals with tumours, modulating the activity of the immune system and promoting improvements in the individual’s general metabolic condition.