Lean Body Mass Associated with Upper Body Strength in Healthy Older Adults While Higher Body Fat Limits Lower Extremity Performance and Endurance.
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.
School of Medicine and Statistical Consulting Centre, University of Wollongong, New South Wales 2522, Australia. karenc@uow.edu.au.
Karen
K
Charlton
Statistical Consulting Services, National Institute of Applied Statistics Research Australia, University of Wollongong, Wollongong, New South Wales 2522, Australia. marijka@uow.edu.au.
Marijka
M
Batterham
School of Medicine and Statistical Consulting Centre, University of Wollongong, New South Wales 2522, Australia. kl704@uowmail.edu.au.
Kelly
K
Langford
School of Medicine and Statistical Consulting Centre, University of Wollongong, New South Wales 2522, Australia. jennalateo@gmail.com.
Jenna
J
Lateo
School of Medicine and Statistical Consulting Centre, University of Wollongong, New South Wales 2522, Australia. eeb786@uowmail.edu.au.
Erin
E
Brock
School of Medicine and Statistical Consulting Centre, University of Wollongong, New South Wales 2522, Australia. kwalton@uow.edu.au.
Karen
K
Walton
School of Exercise and Health Sciences, Edith Cowan University, Joondalup WA 6027, Australia. p.lyons-wall@ecu.edu.au.
Philippa
P
Lyons-Wall
School of Medicine and Statistical Consulting Centre, University of Wollongong, New South Wales 2522, Australia. katie_e@balancepodiatry.com.au.
Katie
K
Eisenhauer
School of Medicine and Statistical Consulting Centre, University of Wollongong, New South Wales 2522, Australia. Nick.Green@bupa.com.au.
Nick
N
Green
School of Medicine and Statistical Consulting Centre, University of Wollongong, New South Wales 2522, Australia. camo.mclean@bigpond.com.
Cameron
C
McLean
D000203:Activities of Daily Living; D050154:Adiposity; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D004032:Diet; D017097:Electric Impedance; D005080:Exercise Test; D005260:Female; D015577:Geriatric Assessment; D064368:Healthy Volunteers; D006801:Humans; D035002:Lower Extremity; D008297:Male; D008875:Middle Aged; D053580:Muscle Strength; D018482:Muscle, Skeletal / Q000502:physiology*; D015596:Nutrition Assessment; D009752:Nutritional Status; D010807:Physical Endurance; D010809:Physical Fitness; D011795:Surveys and Questionnaires
body composition; lean body mass; older people; physical function; protein; upper body strength