Background: Lower muscle and higher fat mass are characteristics of older adults; their physical function is also characterized by slower gait speed and weaker strength. However, the association between specific body composition and physical function is unclear.
Methods: We examined the association between body composition and physical performance using combined cross-sectional data of 1,821 participants from 13 clinical studies at Wake Forest University that used a consistent battery of tests. All participants were ≥60 years old and had one of the following conditions: healthy, osteoarthritis, coronary artery disease, obesity, heart failure, at elevated risk for disability, renal transplantation candidates, heart failure with preserved ejection fraction, moderate self-reported disability, hypertension, diabetes, or coronary artery disease, at high risk for cardiovascular disease. Data at enrollment from each study using uniform tools including body mass index (BMI), dual energy x-ray absorptiometry, physical performance assessment using 4 m walk speed, five chair rise time, handgrip strength, short physical performance battery (17), and Pepper Assessment Tool for Disability were analyzed.
Results: Increased BMI was associated with slower walk speed, lower short physical performance battery, and higher Pepper Assessment Tool for Disability score. Increased percentage of body fat was associated with slower walk speed, lower hand grip strength, lower short physical performance battery scores, and higher Pepper Assessment Tool for Disability scores. Percent appendicular lean mass was associated with faster walk speed, higher handgrip strength, higher short physical performance battery, and lower Pepper Assessment Tool for Disability score. There were no significant discrepancies in relationship between body composition and physical function by gender except gender and BMI on chair-rise time.
Conclusions: Higher BMI and percent body fat were associated with poor physical function while percent appendicular lean mass was associated with better physical function. There was no significant discrepancy in the by gender.
Keywords: 4 m walk speed; BMI; Body composition; Body percent (%) fat; Percent appendicular lean mass; Physical function; SPPB.