Phase angle predicts physical function in older adults

Abstract

Background: Phase angle (PhA) is recognized as an indicator of cellular health and may be a useful marker of physical functions in geriatric populations.

Aims: We aim to analyse the ability of the Phase angle (PhA) to predict the physical function in older adults.

Method: 113 healthy older adults (67 female and 46 male) performed physical tests using the Fullerton Battery - Senior Fitness Test, to assess their physical fitness. Bioelectrical impedance spectroscopy was used to determine PhA at 50KHz and dual-energy x-ray absorptiometry to assess body composition.

Results: PhA was positively associated with functional fitness composite, chair stand, arm curl and 6 min walk test and negatively related with chair sit-and-reach and 8-foot and go (p < 0.05). Even after adjusting for potential confounding variables such as age, sex and appendicular lean soft tissue, PhA showed an association with arm curl (ß = 0.23,p = 0.038), and 8-foot and go (ß=-0.214,p = 0.042).

Conclusions: Higher values of PhA are related with a better physical function. Regardless of sex, age, and skeletal muscle, PhA predicts body strength, agility and dynamic balance in healthy older adults.

Keywords: BIS; Body composition; Elderly; Functional fitness; Physical fitness tests.