Effects of daily walking on intermuscular adipose tissue accumulation with age: a 5-year follow-up of participants in a lifestyle-based daily walking program.

Abstract

Intermuscular adipose tissue (IMAT) accumulates with age. However, there has been no long-term intervention study examining whether daily walking prevents or decreases the age-related IMAT accumulation. The purpose of this study was to determine effects of a long-term lifestyle-based daily walking program on age-related IMAT accumulation after a 5-year follow-up. Using a pedometer, daily step count was evaluated for 5years in 24 middle-aged and elderly male and female participants. Using magnetic resonance imaging, thigh muscle, thigh subcutaneous adipose tissue, IMAT, abdominal subcutaneous adipose tissue, and visceral adipose tissue were examined at baseline and after 5years. After 5 years, there was no significant increase in IMAT in all participants. In addition, IMAT significantly decreased in participants with a daily step count of > 9000 (4.0 ± 2.1 vs. 3.1 ± 1.6cm2; p < 0.05). Moreover, changes in IMAT within 5years correlated with changes in daily step counts, even after adjusting for confounding factors (p < 0.05). Long-term lifestyle-based daily walking program prevented the age-related IMAT accumulation in middle-aged and elderly adults. Furthermore, increased daily walking correlated with decreased IMAT over 5years.