Published in the British Journal of Nutrition, the study looked at 45 women with an average age of 64. The women were assigned to different groups: strength training for 90 days without supplementation, strength training for 90 days with 2 g of fish oil per day or 2 g per day fish oil for 60 days followed by strength training and fish oil for 90 days.
Training was performed three times per week and included floor and upright hip, leg, knee and foot exercises. Various immune parameters were tested before supplementation as well as before and after training.
Age is said to deregulate immune systems, making elderly people more vulnerable to infectious, chronic degenerative, autoimmune and malignant diseases. Physical activity and diet also play a role in moderating immune system responses. While mild physical activity has been seen to increase T-cells, excessive exercise negatively impacts inflammatory response.
The researchers from the Paraná Federal University and the Pequeno Príncipe Research Institute in Brazil found: “The immune parameters improved in response to fish oil supplementation; however, strength training alone did not enhance the immune system.”
Fish oil improved the immune system by increasing the functioning of the white blood cells neutrophils, the proliferation of CD4þ and CD8þ lymphocytes which fight against infections and the production of lymphocyte cytokines - important small proteins for cell signalling in the immune system.
The activity of neutrophils improved in response to the 2 g per day supplementation.
Production of cytokines IL-2 and IFN-g also changed. They increased after supplementation by 80% and 60%, respectively. After supplementation and exercise they increased by 85 and 88%, respectively.
"These increases highlight the modulatory effects of fish oil and exercise in the elderly, which is helpful in restoring the immunity balance," they wrote.
The fish oil capsules contained 180 g EPA and 120 g DHA per kg.
Diet was monitored by a food diary of a day before and after training to check there were no changes in dietary intake.
The researchers said further research with a bigger sample size and greater health screening was now called for.
Source: British Journal of Nutrition
Published online ahead of print, DOI: http://dx.doi.org/10.1017/S0007114515001555
“Influence of fish oil supplementation and strength training on some functional aspects of immune cells in healthy elderly women”
Authors: C. Lourdes Nahhas Rodacki, A. Luiz Felix Rodacki, I. Coelho, D. Pequito, M. Krause, S. Bonatto, K. Naliwaiko and L. Cláudio Fernandes