Lower physical activity is associated with higher intermuscular adipose tissue in people with type 2 diabetes and peripheral neuropathy

Abstract

Background. Increased lipid accumulation in skeletal muscle has been linked to insulin resistance, impaired muscle performance, and impaired physical function. It is unclear whether physical activity is associated with lipid content in skeletal muscle, muscle performance, or overall physical function. Objective. The purpose of this study was to characterize physical activity levels (average daily step count) in a sample of people with diabetes and peripheral neuropathy and to determine the relationship among step count, intermuscular adipose tissue volume (IMAT), muscle performance (peak torque, power), and physical function. Design. A cross-sectional design was used in this study. Methods. Twenty-two people with diabetes and peripheral neuropathy (15 men and 7 women, mean age=64.5 years [SD=12.7], and mean body mass index-33.2 kg/m2 [SD=6.4]) participated. Average daily step count, glycosylated hemoglobin, modified 9-item Physical Performance Test scores, Six-Minute Walk Test distance, calf intermuscular adipose tissue volume (via magnetic resonance imaging), and isokinetic dynamometry of the ankle muscles were recorded. Results. Average daily step count was 7,754 (SD=4,678; range=3,088-20,079). Five participants had an average daily step count greater than 10,000. Average IMAT volume was 84 cm3 (SD=88). Greater average daily step count was associated with younger age (r=-.39, P