Dataset Information

Analysis and Interpretation of Accelerometry Data in Older Adults: The LIFE Study.

ABSTRACT:

Background

Accelerometry has become the gold standard for evaluating physical activity in the health sciences. An important feature of using this technology is the cutpoint for determining moderate to vigorous physical activity (MVPA) because this is a key component of exercise prescription. This article focused on evaluating what cutpoint is appropriate for use with older adults 70-89 years who are physically compromised.

Methods

The analyses are based on data collected from the Lifestyle Interventions and Independence for Elders (LIFE) study. Accelerometry data were collected during a 40-minute, overground, walking exercise session in a subset of participants at four sites; we also used 1-week baseline and 6-month accelerometry data collected in the main trial.

Results

There was extreme variability in median counts per minute (CPM) achieved during a controlled bout of exercise (n = 140; median = 1,220 CPM (25th, 75th percentile = 715, 1,930 CPM). An equation combining age, age(2), and 400 m gait speed explained 61% of the variance in CPM achieved during this session. When applied to the LIFE accelerometry data (n = 1,448), the use of an individually tailored cutpoint based on this equation resulted in markedly different patterns of MVPA as compared with using standard fixed cutpoints.

Conclusions

The findings of this study have important implications for the use and interpretations of accelerometry data and in the design/delivery of physical activity interventions with older adults.

SUBMITTER: Rejeski WJ

PROVIDER: S-EPMC5175451 | biostudies-literature | 2016 Apr

REPOSITORIES: biostudies-literature

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Publications

Analysis and Interpretation of Accelerometry Data in Older Adults: The LIFE Study.

Rejeski W Jack WJ Marsh Anthony P AP Brubaker Peter H PH Buman Matthew M Fielding Roger A RA Hire Don D Manini Todd T Rego Alvito A Miller Michael E ME

The journals of gerontology. Series A, Biological sciences and medical sciences 20151029 4

<h4>Background</h4>Accelerometry has become the gold standard for evaluating physical activity in the health sciences. An important feature of using this technology is the cutpoint for determining moderate to vigorous physical activity (MVPA) because this is a key component of exercise prescription. This article focused on evaluating what cutpoint is appropriate for use with older adults 70-89 years who are physically compromised.<h4>Methods</h4>The analyses are based on data collected from the ...[more]

PMID: 26515258

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Project description:BackgroundOlder adults receive important health benefits from more robust social capital. Yet, the mechanisms behind these associations are not fully understood. Some evidence suggests that higher levels of social capital ultimately affect health through alterations in physical activity (PA), but most of this research has relied on self-reported levels of PA. The aim of this study was to determine whether components of social capital, including social network size and composition as well as the frequency of participation in various social and community activities, were associated with accelerometry-measured PA levels in a nationally representative sample of community-dwelling older adults (≥ 62 years).MethodsWe conducted a cross-sectional analysis using data from the wrist accelerometry sub-study (n = 738) within Wave 2 of the National Social, Health, and Aging Project (NSHAP), a population-based longitudinal study that collects extensive survey data on the physical, cognitive, and social health of older adults. Participants' physical activity was measured with a wrist accelerometer worn for 72 consecutive hours. We related seven, self-reported social relationship variables (network size, network proportion friends, and frequencies of socializing with friends and family, visiting with neighbors, attending organized group meetings, attending religious services, and volunteering) to accelerometer-measured PA (mean counts-per-minute) using multivariate linear regression analysis, while adjusting for potential confounders.ResultsLarger social networks (p = 0.042), higher network proportion friends (p = 0.013), more frequent visiting with neighbors (p = 0.009), and more frequent attendance at organized group meetings (p = 0.035) were associated with higher PA levels after controlling for demographic and health covariates. Volunteering was significant prior to adjusting for covariates. No significant associations were found between frequencies of socializing with friends and relatives or attendance at religious services and PA.ConclusionsThis study suggests social capital is significantly related to objectively measured PA levels among older adults, and that friendships as well as social participation in groups and with neighbors may be particularly pertinent to PA. These findings expand our understanding of and offer a potential mechanism linking social relationships and overall health among older adults. They also have implications for how we might motivate older adults to be more physically active.

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Dataset Information

Analysis and Interpretation of Accelerometry Data in Older Adults: The LIFE Study.

Background

Methods

Results

Conclusions

Publications

Analysis and Interpretation of Accelerometry Data in Older Adults: The LIFE Study.

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