Body composition associations with muscle strength in older adults living in Auckland, New Zealand.

Abstract

BackgroundAging is associated with decreases in muscle strength and simultaneous changes in body composition, including decreases in muscle mass, muscle quality and increases in adiposity.MethodsAdults (n = 369; 236 females) aged 65-74 years living independently were recruited from the cross-sectional Researching Eating Activity and Cognitive Health (REACH) study. Body fat percentage and appendicular skeletal muscle mass (ASM) (sum of lean mass in the arms and legs) were assessed using Dual-energy X-ray Absorptiometry (Hologic, QDR Discovery A). The ASM index was calculated by ASM (kilograms) divided by height (meters) squared. Isometric grip strength was measured using a hand grip strength dynamometer (JAMAR HAND).ResultsLinear regression analyses revealed that muscle strength was positively associated with the ASM index (R2 = 0.431, p ConclusionsBody fat percentage should be considered when measuring associations between muscle mass and muscle strength in older adults.