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Fish oil and resistance training – effective for older adults?

Omega-3 fatty acids have been long touted for their cardiovascular benefits. But many research studies strongly suggest that these fatty acids exert improvements well beyond those related to heart health.

 

Omega-3 fatty acids and/or fish oil supplements (the latter being a rich source of omega-3s) have been administered to those with cancer, heart disease, rheumatoid arthritis, and psychiatric disorders (i.e. schizophrenia and major depressive disorder) with resultant improvements in disease-specific outcomes and body composition (read: more and/or better quality of muscle) (1, 2). The supplement also has essentially no side effects, aside from the occasional lingering fishy after-taste. It’s thought that these beneficial effects are due to omega-3’s inhibition of numerous pro-inflammatory pathways.

So is there a place for these supplements in healthy populations? Say, exercising older adults? This is exactly what Mariasole Da Boit and a group of colleagues investigated in a randomized, double-blind placebo controlled trial published in the American Journal of Clinical Nutrition earlier this year (3). Fifty men and women (age 70.6 ± 4.5) participated in a resistance exercise training program for lower limbs twice weekly for 18 weeks. All were randomized to 3g fish oil/day or placebo (3g safflower oil/day). In women, maximal isometric torque (static contraction) and muscle quality defined by torque per unit of muscle cross-sectional area improved more in the fish oil group, independent of muscle mass changes; no differences were observed in men. Plasma triglycerides decreased in both sexes, while maximal isokinetic torque (moving contraction), 4-minute walk test, chair-rise time, muscle size, and muscle fat did not differ. The authors speculate that omega-3 improves neuromuscular function and/or enhances the contractile properties of type II (fast-twitch) muscle fibers. Some findings suggest that older women do not increase muscle strength to the same degree as older men; thus women could undergo a more profound response to resistance training since there is a greater capacity for muscular improvement.

While this is only one study and the mechanisms behind the results are somewhat speculative, the results are promising. With forthcoming research, omega-3 fatty acid supplements might become an evidence-based recommendation for healthy community-dwelling older adults and many clinical populations.

  1. Lee S, Gura KM, Kim S, Arsenault DA, Bistrian BR, Puder M. Current clinical application of omega-6 and omega-3 fatty acids. Nutrition in Clinical Practice 2006; 21(4):323-41
  2. Murphy RA, Mourtzakis M, Chu QS, Baracos VE, Reiman T, Mazurak VC. Nutritional intervention with fish oil provides a benefit over standard of care for weight and skeletal muscle mass in patients with nonsmall cell lung cancer receiving chemotherapy. Cancer 2011;117(8):1775-82.
  3. Da Boit , Sibson R, Sivasubramaniam S, Meakin JR, Greig CA, Aspden RM, et al. Sex differences in the effect of fish-oil supplementation on the adaptiveresponse to resistance exercise training in older people: a randomized controlled trial. American Journal of Clinical Nutrition 2017; 105:151-8

Eat More Berries!

The session held Thursday afternoon on Aging and Cognition presented by Barbara Shukitt-Hale, PhD focused on the increase in inflammation and oxidative stress in brain aging.
Thirty percent of the United States population is over the age of 65. If these individuals suffer from decreased motor and cognitive function there could be a healthcare crisis in this country.
Dr. Shukitt-Hale and her staff have conducted several research studies looking at impaired motor performance and cognitive function in aging rats. Their results showed a  decrease in motor behavior, learning,  and spatial memory.
Their research question was whether this impaired function could be stopped or improved by altering the diet of the rats.  They specifically looked at polyphenols found in dark fruit and vegetables, wine, chocolate, and walnuts.
Polyphenols show many neuroprotective features such as anti-inflammation, antioxidants, and reduced risk of cardiovascular disease and cancer as well as improved vision.
The overall findings of their research show that nutrition intervention can forestall age related deficits in learning and memory and reverses deficits in learning and memory and declines in motor behavior performance.
But, can this translate to humans now becomes the question. The research group expanded their studies to assess exactly that.
Initial studies looked at the effects of aging on balance, gait, and cognition. Both cognition and mobility decrease with age and these declines are measurable at younger ages than expected.
The introduction of blueberries and strawberries into the diet of their human subjects improved both the measures of executive function and spatial recognition.
Their results showed:
  • Berries can reduce proinflammatory signals in cells
  • Functional declines in mobility and cognition are key features of aging
  • Berry fruit can improve cognition
  • Different berry fruits affect different aspects of cognition
In summary, polyphenols have direct effects on the brain and they can reverse age related declines.
And most importantly, eat more berries!