Lean Body Mass Associated with Upper Body Strength in Healthy Older Adults While Higher Body Fat Limits Lower Extremity Performance and Endurance

Nutrients. 2015 Aug 26;7(9):7126-42. doi: 10.3390/nu7095327.

Abstract

Impaired strength adversely influences an older person's ability to perform activities of daily living. A cross-sectional study of 117 independently living men and women (age = 73.4 ± 9.4 year; body mass index (BMI) = 27.6 ± 4.8 kg/m²) aimed to assess the association between body composition and: (1) upper body strength (handgrip strength, HGS); (2) lower extremity performance (timed up and go (TUG) and sit to stand test (STS)); and (3) endurance (6-minute walk (SMWT). Body composition (% fat; lean body mass (LBM)) was assessed using bioelectrical impedance. Habitual physical activity was measured using the Minnesota Leisure Time Physical Activity Questionnaire (MLTPA) and dietary macronutrient intake, assessed using 24 h recalls and 3-day food records. Regression analyses included the covariates, protein intake (g/kg), MLTPA, age and sex. For natural logarithm (Ln) of right HGS, LBM (p < 0.001) and % body fat (p < 0.005) were significant (r² = 46.5%; p < 0.000). For left LnHGS, LBM (p < 0.000), age (p = 0.036), protein intake (p = 0.015) and LnMLTPA (p = 0.015) were significant (r² = 0.535; p < 0.000). For SMW, % body fat, age and LnMLTPA were significant (r² = 0.346; p < 0.000). For STS, % body fat and age were significant (r² = 0.251; p < 0.000). LBM is a strong predictor of upper body strength while higher % body fat and lower physical activity are associated with poorer outcomes on tests of lower extremity performance.

Keywords: body composition; lean body mass; older people; physical function; protein; upper body strength.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Activities of Daily Living
  • Adiposity*
  • Age Factors
  • Aged
  • Aged, 80 and over
  • Aging*
  • Body Mass Index*
  • Cross-Sectional Studies
  • Diet
  • Electric Impedance
  • Exercise Test
  • Female
  • Geriatric Assessment
  • Healthy Volunteers
  • Humans
  • Lower Extremity
  • Male
  • Middle Aged
  • Muscle Strength*
  • Muscle, Skeletal / physiology*
  • Nutrition Assessment
  • Nutritional Status
  • Physical Endurance*
  • Physical Fitness*
  • Surveys and Questionnaires