The Role of the Environment on Sedentary Behavior in Community-Dwelling Older Adults.

OBJECTIVES: To compare amounts of sedentary behavior and physical activity in adults residing in planned group residential settings to those residing in private homes. METHODS: Thirty-one older adults who resided in planned group residential settings (n=13) and in private homes (n=18) participated. Daily activities were measured using the Sensewear Armband for 7 days. Estimates of the duration of daily activities performed across sedentary, light, and moderate-to-vigorous intensities were captured. RESULTS: Participants in planned group residential settings were older (age 85.9±3.5 vs 78.3±7.2; p=0.001) and spent more time in sedentary behaviors (12.7±1.5 vs 11.3±1.6; p=0.02) than participants in private homes. The difference was attenuated slightly after controlling for age and wear time (adjusted difference 1.2±0.6 hours, p=0.06). DISCUSSION: Adults residing in planned group residential settings, which provide supportive services, were more sedentary than adults residing in private homes. The environment in which older adults live may contribute to sedentary behavior.

Motor Control-based Group Exercise: Can It be Delivered as Effectively by Lay Leaders?

PURPOSE: On the Move (OTM), a motor control-based group exercise program for community-dwelling older adults, has produced greater gains in mobility than a standard group exercise program when delivered by research leaders. The purposes of this study were:1) to examine the effectiveness of OTM versus a standard program when delivered by lay leaders and 2) to compare the outcomes of OTM when delivered by research versus lay leaders. METHODS: Community-dwelling, medically stable older adults who could walk household distances participated. OTM consisted of warm-up, timing and coordination, strengthening, and stretching exercises. The seated standard program consisted of warm-up, aerobic, strengthening and stretching exercises. The primary outcome(s) of function and disability was the Late Life Function and Disability Instrument (LLFDI), and for walking ability were the Six Minute Walk Test and gait speed. RESULTS: 126 participants (mean age = 80.7±7.8 years, gait speed = 0.91 m/s) were randomized to OTM (n=49) or standard (n=77) programs. When taught by lay leaders, there were no significant between-intervention group differences in any of the outcomes (p>0.10). Comparing OTM outcomes between leaders, there was a statistical but not clinically meaningful difference in LLFDI disability (1.87±0.89, p=0.04) when taught by research versus lay leader, and moderate differences (p=0.06) in LLFDI overall function (1.89±1.02) and gait speed (0.05±0.03). Qualitative interview responses suggest that instructor-related concerns may have impacted program outcomes. CONCLUSION: When delivered by lay leaders OTM was not more effective than a standard program for improving function, disability, and mobility in older adults. Health promotion programs designed to improve mobility in community-dwelling older adults and based on a motor control theoretical background, may be best taught by rehabilitation professionals.

The Test-Retest Reliability of Indirect Calorimetry Measures of Energy Expenditure During Overground Walking in Older Adults With Mobility Limitations.

The purpose of this study was to assess the relative and absolute reliability of metabolic measures of energy expenditure and gait speed during overground walking in older adults with mobility limitations. Thirty-three (mean age [SD] = 76.4 [6.6] years; 66% female) older adults with slow gait participated. Measures of energy expenditure and gait speed were recorded during two 6-min bouts of overground walking (1 week apart) at a self-selected "usual" walking pace. The relative reliability for all variables was excellent: ICC = .81-.91. Mean differences for five of the six outcome variables was less than or equal to the respected SEM, while all six mean differences fell below the calculated MDC95. Clinicians and researchers can be confident that metabolic measures of energy expenditure and gait speed in older adults with slow walking speeds can be reliably assessed during overground walking, providing an alternative to traditional treadmill assessments.

The Influence of Body Mass Index on Self-report and Performance-based Measures of Physical Function in Adult Women.

PURPOSE: Little is known about limitations in physical function across BMI categories in middle aged women using both self-report and performance-based measures. Furthermore, the impact of BMI on the measurement of function has not been explored. The purpose of this study was to assess physical function in adult women across BMI categories using self-report and performance-based measures and determine the influence of BMI on the relationship between the measures. METHODS: Fifty sedentary females (10 in each BMI category: normal weight, overweight, obese class I, II, and III) aged 51.2 ± 5.4 years participated. Assessments included demographics, past medical history, physical activity level, BMI, and self-report (Late Life Function and Disability Instrument) and performance-based measures of physical function (6-Minute Walk Test, timed chair rise, gait speed). Physical function was compared between BMI categories using analysis of variance. The influence of BMI on the relationship of self-report and performance-based measures was analyzed using linear regression. RESULTS: Compared to those that were normal weight or overweight, individuals with obesity scored lower on the self-report measure of physical function (LLFDI) for capability in participating in life tasks and ability to perform discrete functional activities. On the performance-based measures, the individuals with obesity had slower gait speed compared to the normal and overweight weight groups. For the 6-Minute Walk Test and timed chair stands, individuals with obesity had poorer performance compared to those who were normal weight. Linear regression analyses revealed that BMI attenuated the relationship between the self-report and performance-based measures by approximately 50%. CONCLUSIONS: While those with severe obesity were most impaired, adult women with less severe obesity also demonstrated significant decrements in physical function.