Fish Oil and Muscle Function

• Evaluate the effect of omega-3 fatty acids on muscle mass [ Time Frame: Change from baseline in muscle mass at 24 weeks in older adults only ] [ Designated as safety issue: No ]
  We will measure thigh muscle volume by using magnetic resonance imaging. These measurements will also be assessed at week 12 in a subset of subjects but the data will not be used as a primary outcome measure.
  
  
• Evaluate the effect of omega-3 fatty acids on physical function [ Time Frame: Change from baseline in physical function at 24 weeks in older adults only ] [ Designated as safety issue: No ]
  We will evaluate muscle strength by assessing one-repetition maximum strength of upper- and lower-body skeletal muscles, grip strength and isometric and isokinetic force development. We will assess overall physical function using the physical performance tests, which evaluates the ability to perform usual daily activities such as climbing a flight of stairs, walking 50 feet and putting on and removing a coat. These measurements will also be assessed at week 12 in a subset of subjects but the data will not be used as a primary outcome measure.
  
  

• Evaluate the effect of aging on muscle mass [ Time Frame: During baseline testing in both young and older subjects ] [ Designated as safety issue: No ]
  We will measure total fat-free mass by duel X-ray absorptiometry, thigh muscle and intermuscular fat volumes by using magnetic resonance imaging.
  
  
• Evaluate the effect of aging on physical function [ Time Frame: During baseline testing in both young and older subjects ] [ Designated as safety issue: No ]
  We will evaluate muscle strength by assessing one-repetition maximum strength of upper- and lower-body skeletal muscles, grip strength, thigh isometric and isokinetic force development and time-to-peak force development during thigh isokinetic exercises. We will assess overall physical function using the physical performance tests, which evaluates the ability to perform usual daily activities such as climbing a flight of stairs, walking 50 feet and putting on and removing a coat.
  
  

Loss of muscle mass is a normal consequence of aging in many older adults, worsened by chronic illness, poor appetite and diet, and reduced physical activity. The ensuing decline in physical function is a major cause of frailty, disability and death. Treatments that can reverse or reduce the age-associated loss of muscle mass are therefore much needed. Evidence is emerging that consumption of fish or fish oil derived long-chain omega-3 polyunsaturated fatty acids (LCn-3PUFA) may be important for maintenance of muscle mass and physical function throughout the life-span. However, the effect of LCn-3PUFA supplementation on muscle mass, muscle strength and overall physical function is not known. The goal of this study therefore is to determine the effect of LCn-3PUFA supplementation on muscle mass, muscle strength and physical function in older adults.