Positive Health Online

Abstract

DA BOIT and COLLEAGUES, 1. Institute of Medical Sciences and; 2. Exeter MR Research Centre, University of Exeter, Exeter, United Kingdom; 3. School of Sport, Exercise and Rehabilitation Sciences and; 4. Medical Research Council Arthritis Research United Kingdom Centre for Musculoskeletal Ageing Research, University of Birmingham, Birmingham, United Kingdom; 5. Faculty of Health Sciences and Sport, University of Stirling, Stirling, United Kingdom; 6. School of Biological Sciences, University of Aberdeen, Aberdeen, United Kingdom; 7. Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China; 8. Department of Clinical Pharmacology, School of Medicine, Flinders University, Adelaide, Australia; and 9. Scottish Universities Environmental Research Centre, University of Glasgow, Glasgow, United Kingdom 10. Institute of Medical Sciences and stuart.gray@glasgow.ac.uk sought to determine the effects of long-chain n-3 PUFA supplementation on resistance exercise training-induced increases in muscle mass and function and whether these effects differ between older men and women.

Background

Resistance exercise increases muscle mass and function in older adults, but responses are attenuated compared with younger people. Data suggest that long-chain n-3 polyunsaturated fatty acids (PUFAs) may enhance adaptations to resistance exercise in older women. To our knowledge, this possibility has not been investigated in men.

Methodology

Objective: The authors sought to determine the effects of long-chain n-3 PUFA supplementation on resistance exercise training-induced increases in muscle mass and function and whether these effects differ between older men and women. Design: Fifty men and women [men: n = 27, mean ± SD age: 70.6 ± 4.5 y, mean ± SD body mass index (BMI; in kg/m2): 25.6 ± 4.2; women: n = 23, mean ± SD age: 70.7 ± 3.3 y, mean ± SD BMI: 25.3 ± 4.7] were randomly assigned to either long-chain n-3 PUFA (n = 23; 3 g fish oil/d) or placebo (n = 27; 3 g safflower oil/d) and participated in lower-limb resistance exercise training twice weekly for 18 wk. Muscle size, strength, and quality (strength per unit muscle area), functional abilities, and circulating metabolic and inflammatory markers were measured before and after the intervention.

Results

Maximal isometric torque increased after exercise training to a greater (P < 0.05) extent in the long-chain n-3 PUFA group than in the placebo group in women, with no differences (P > 0.05) between groups in men. In both sexes, the effect of exercise training on maximal isokinetic torque at 30, 90, and 240° s-1, 4-m walk time, chair-rise time, muscle anatomic cross-sectional area, and muscle fat did not differ (P > 0.05) between groups. There was a greater (P < 0.05) increase in muscle quality in women after exercise training in the long-chain n-3 PUFA group than in the placebo group, with no such differences in men (P > 0.05). Long-chain n-3 PUFAs resulted in a greater decrease (P < 0.05) than the placebo in plasma triglyceride concentrations in both sexes, with no differences (P > 0.05) in glucose, insulin, or inflammatory markers.

Conclusion

Long-chain n-3 PUFA supplementation augments increases in muscle function and quality in older women but not in older men after resistance exercise training. This trial was registered at clinicaltrials.gov as NCT02843009.

References

Da Boit M1, Sibson R1, Sivasubramaniam S1, Meakin JR2, Greig CA3,4, Aspden RM1, Thies F1, Jeromson S5, Hamilton DL5, Speakman JR6,7, Hambly C6, Mangoni AA8, Preston T9, Gray SR10. Sex differences in the effect of fish-oil supplementation on the adaptive response to resistance exercise training in older people: a randomized controlled trial. Am J Clin Nutr.;105(1):151-158. doi: 10.3945/ajcn.116.140780  Epub 2016 Nov 16. Jan 2017.

 

Comment

The above research demonstrated that long-chain n-3 PUFA supplementation augments increases in muscle function and quality in older women but not in older men after resistance exercise training.