Deakin University
Browse

File(s) under permanent embargo

Association of sitting time and breaks in sitting with muscle mass, strength, function, and inflammation in community-dwelling older adults

journal contribution
posted on 2018-06-01, 00:00 authored by N Reid, G N Healy, Jenny GianoudisJenny Gianoudis, M Formica, P A Gardiner, E E Eakin, Caryl NowsonCaryl Nowson, Robin DalyRobin Daly
The mechanisms through which excessive sitting time impacts health are important to understand. This study found that each hour of sitting per day was not associated with physical function, although associations with poor body composition were observed. Reducing sitting time for improved weight management in older adults needs further exploration. INTRODUCTION: To examine the association of sitting time and breaks in sitting time with muscle mass, strength, function, and inflammation in older Australians. METHODS: Data from the thigh-worn activPAL3™ monitor (7-day continuous wear) was used to derive time spent sitting (hours) and total number of sit-stand transitions per day. Body composition (dual energy X-ray absorptiometry), lower-body muscle strength, function (timed up-and-go [TUG], 4-m gait speed, four square step test, 30-second sit-to-stand), and serum inflammatory markers (interleukin-[IL-6], IL-8, IL-10, tumor necrosis factor-alpha [TNF-α], and adiponectin) were measured. Multiple regression analyses, adjusted for age, sex, ethnicity, education, employment status, marital status, number of prescription medications, smoking status, vitamin D, and stepping time, were used to assess the associations. RESULTS: Data from 123 community-dwelling older adults (aged 65-84 years, 63% female) were used. Total daily sitting time was associated with lower percentage lean mass (β [95%CI], - 1.70% [- 2.30, - 1.10]) and higher total body fat mass (2.92 kg [1.94, 3.30]). More frequent breaks in sitting time were associated with a 45% reduced risk of having pre-sarcopenia (OR = 0.55; 95% CI 0.34, 0.91; model 1), defined as appendicular lean mass divided by BMI. No significant associations were observed for sitting time or breaks in sitting with measures of muscle strength, function, or inflammation. CONCLUSION: In older community-dwelling adults, greater sitting time was associated with a lower percentage lean mass, while more frequent breaks in sitting time were associated with lower odds of having pre-sarcopenia. This suggests that reducing sedentary time and introducing frequent breaks in sedentary time may be beneficial for improving body composition in healthy older adults.

History

Journal

Osteoporosis international

Volume

29

Issue

6

Pagination

1341 - 1350

Publisher

Springer

Location

London, Eng.

ISSN

0937-941X

eISSN

1433-2965

Language

eng

Publication classification

C Journal article; C1 Refereed article in a scholarly journal

Copyright notice

2018, International Osteoporosis Foundation and National Osteoporosis Foundation