Association between muscle mass, leg strength, and fat mass with physical function in older adults: influence of age and sex

J Aging Health. 2011 Mar;23(2):313-28. doi: 10.1177/0898264310388562. Epub 2010 Nov 16.


Objective: The purposes of this study were to determine the relationship between muscle mass, muscle strength, muscle quality, and fat mass with a composite measure of physical function in older adults, and to determine whether these relations differed by age and sex.

Method: Participants consisted of 1280 adults aged ≥ 55 yr from the NHANES study. Reduced rank regression was used to identify patterns of muscle mass, muscle strength, muscle quality, and fat mass related to physical function.

Results: A single relevant pattern emerged that included leg strength and fat mass as predictors of the 7 physical function variables. The leg strength loading was significantly greater than the fat mass loading in men and women aged 55-64 and ≥ 75, and differed between sexes.

Conclusion: Leg strength and fat mass best predict physical function in older adults and the relative importance varies according to age and sex.

MeSH terms

  • Absorptiometry, Photon
  • Age Factors
  • Aged
  • Aging
  • Body Composition
  • Body Mass Index
  • Cross-Sectional Studies
  • Factor Analysis, Statistical
  • Female
  • Health Status
  • Humans
  • Leg / physiology*
  • Male
  • Middle Aged
  • Multivariate Analysis
  • Muscle Contraction / physiology*
  • Muscle Strength / physiology*
  • Muscle, Skeletal / physiology*
  • Nutrition Surveys
  • Regression Analysis
  • Self Report
  • Sex Factors