Assessing Walking Behaviors of Selected Subpopulations

Trajectories of Outdoor Mobility in Vulnerable Community-Dwelling Elderly: The Role of Individual and Environmental Factors

OBJECTIVE

Outdoor mobility is critical for healthy aging, yet little is known about the factors influencing mobility in the frail elderly. We investigated the role of individual and community risk factors on trajectories of mobility in a population of vulnerable community-dwelling elderly.

METHOD

Using data from 1,188 older adults in Detroit, MI, who qualify for federally funded home care, a latent class growth analysis was used to model the frequency of going outside over a 15-month period.

RESULTS

Four latent trajectories were found: those with a low, high, and declining frequency of going outdoors over time, and those who do not go outdoors on a regular basis. Risk factors for membership in the homebound and infrequent mobility groups were older age, more severe mobility impairment, and fear of falling. Barriers at the entry to the home were associated with being homebound.

DISCUSSION

Declining health status and functional limitations are risk factors that pose a threat to outdoor mobility in the frail elderly, while housing barriers and community accessibility also merit attention.

The effects of observation of walking in a living room environment, on physical, cognitive, and quality of life related outcomes in older adults with dementia: a study protocol of a randomized controlled trial

BACKGROUND

The number of older adults with dementia is expected to increase. Dementia is not only characterized by a decline in cognition, also other functions, for example, physical functioning change. A possible means to decrease the decline in these functions, or even improve them, could be increasing the amount of physical activity. A feasible way hereto may be activation of the mirror neuron system through action observation. This method has already been shown beneficial for the performance of actions in, for example, stroke patients. The primary aim of this study is to examine the effect of observing videos of walking people on physical activity and physical performance, in older adults with dementia. Secondary, effects on cognition and quality of life related factors will be examined.

METHODS/DESIGN

A cluster randomized controlled trial is being performed, in which videos are shown to older adults with dementia (also additional eligibility criteria apply) in shared living rooms of residential care facilities. Due to the study design, living rooms instead of individual participants are randomly assigned to the experimental (videos of walking people) or control (videos of nature) condition, by means of drawing pieces of paper. The intervention has a duration of three months, and takes place on weekdays, during the day. There are four measurement occasions, in which physical activity, physical functioning, activities of daily living, cognition, the rest-activity rhythm, quality of life, and depression are assessed. Tests for participants are administered by a test administrator who is blind to the group the participant is in.

DISCUSSION

This study examines the effect of the observation of walking people on multiple daily life functions and quality of life related factors in older adults with dementia. A strength of this study is that the intervention does not require much time and attention from caregivers or researchers. A challenge of the study is therefore to get to know for how long residents watch the videos. However, the design implies a high feasibility of the study, as well as a high applicability of the intervention into daily care.

TRIAL REGISTRATION

NTR4708. Date of registration: 31 July 2014.

Optimizing mobility in later life: the role of the urban built environment for older adults aging in place

Hazards in the urban built environment can create barriers to mobility among older adults aging in place. We investigated the relationship between urban built environment characteristics and 15-month trajectories of mobility disability in a sample of 1,188 older adults living in Detroit, MI, a city that has undergone rapid economic and structural decline. Data come from the Michigan Minimum Data Set for Home Care (2001-2008), an enumerative database of older adults in Michigan who qualify for federal or state-funded home and community-based long-term care through a Medicaid waiver program. Standardized assessments are made at intake and every 90 days by case managers. Built environments were assessed with a virtual audit using the "Street View" feature of Google Earth. A summary accessibility score was created for each block based on a count of the number of accessible features (e.g., continuous barrier-free sidewalks and proximity of public transportation). Using growth mixture models, two latent trajectories of outdoor mobility were identified: one capturing occasional outdoor mobility (representing 83 % of the sample) and one capturing almost no mobility outside the home. Controlling for sociodemographic and health risk factors, individuals living in more accessible environments had a 18 % higher odds of being in the more mobile group (OR = 1.18, 95 % CI = 1.01, 1.41). These findings emphasize the importance of the built environment for mobility among urban-dwelling older adults.

A Systems Perspective on Postural and Gait Stability: Implications for Physical Activity in Aging and Disease

Postural instability, falls, and fear of falling that accompany frailty with aging and disease form major impediments to physical activity. In this article we present a theoretical framework that may help researchers and practitioners in the development and delivery of intervention programs aimed at reducing falls and improving postural stability and locomotion in older individuals and in those with disability due to disease. Based on a review of the dynamical and complex systems perspectives of movement coordination and control, we show that 1) central to developing a movement-based intervention program aimed at fall reduction and prevention is the notion that variability can play a functional role and facilitate movement adaptability, 2) intervention programs aimed at fall reduction should focus more on coordination and stability boundary measures instead of traditional gait and posture outcome variables, and 3) noise-based intervention techniques using stochastic resonance may offer external aids to improve dynamic balance control.

Influences on neighborhood walking in older adults

The purpose of this cross-sectional survey study was to examine the influence of self-efficacy, outcome expectations, and environment on neighborhood walking in older adults with (n = 163, mean age = 78.7, SD = 7.96 years) and without (n = 163, mean age = 73.6, SD = 7.93 years) mobility limitations, controlling for demographic characteristics. Multiple regression revealed that in mobility-limited older adults, demographic characteristics, self-efficacy, and outcome expectations explained 17.4% of variance in neighborhood walking, while environment (neighborhood destinations and design) explained 9.4%. Destinations, self-efficacy, sex, and outcome expectations influenced walking. In those without mobility limitations, demographic characteristics, self-efficacy, and outcome expectations explained 15.6% of the variance, while environment explained 5.6%. Self-efficacy, sex, and design influenced walking. Neighborhood walking interventions for older adults should include self-efficacy strategies tailored to mobility status and neighborhood characteristics.

Secular trends: a ten-year comparison of the amount and type of physical activity and inactivity of random samples of adolescents in the Czech Republic

BACKGROUND

An optimal level of physical activity (PA) in adolescence influences the level of PA in adulthood. Although PA declines with age have been demonstrated repeatedly, few studies have been carried out on secular trends. The present study assessed levels, types and secular trends of PA and sedentary behaviour of a sample of adolescents in the Czech Republic.

METHODS

The study comprised two cross-sectional cohorts of adolescents ten years apart. The analysis compared data collected through a week-long monitoring of adolescents' PA in 1998-2000 and 2008-2010. Adolescents wore either Yamax SW-701 or Omron HJ-105 pedometer continuously for 7 days (at least 10 hours per day) excluding sleeping, hygiene and bathing. They also recorded their number of steps per day, the type and duration of PA and sedentary behaviour (in minutes) on record sheets. In total, 902 adolescents (410 boys; 492 girls) aged 14-18 were eligible for analysis.

RESULTS

Overweight and obesity in Czech adolescents participating in this study increased from 5.5% (older cohort, 1998-2000) to 10.4% (younger cohort, 2008-2010). There were no inter-cohort significant changes in the total amount of sedentary behaviour in boys. However in girls, on weekdays, there was a significant increase in the total duration of sedentary behaviour of the younger cohort (2008-2010) compared with the older one (1998-2000). Studying and screen time (television and computer) were among the main sedentary behaviours in Czech adolescents. The types of sedentary behaviour also changed: watching TV (1998-2000) was replaced by time spent on computers (2008-2010).The Czech health-related criterion (achieving 11,000 steps per day) decreased only in boys from 68% (1998-2000) to 55% (2008-2010). Across both genders, 55%-75% of Czech adolescents met the health-related criterion of recommended steps per day, however less participants in the younger cohort (2008-2010) met this criterion than in the older cohort (1998-2000) ten years ago. Adolescents' PA levels for the monitored periods of 1998-2000 and 2008-2010 suggest a secular decrease in the weekly number of steps achieved by adolescent boys and girls.

CONCLUSION

In the younger cohort (2008-2010), every tenth adolescent was either overweight or obese; roughly twice the rate when compared to the older cohort (1998-2000). Sedentary behaviour seems relatively stable across the two cohorts as the increased time that the younger cohort (2008-2010) spent on computers is compensated with an equally decreased time spent watching TV or studying. Across both cohorts about half to three quarters of the adolescents met the health-related criterion for achieved number of steps. The findings show a secular decrease in PA amongst adolescents. The significant interaction effects (cohort × age; and cohort × gender) that this study found suggested that secular trends in PA differ by age and gender.

Protein consumption following aerobic exercise increases whole-body protein turnover in older adults

Research measuring whole-body protein turnover (WBPT) after both exercise and nutrition has generally focused on resistance exercise; however, there is a paucity of data regarding the effect of postaerobic exercise nutrition, especially in older adults. It is not known if postexercise protein feeding has a beneficial effect on protein turnover after low- to moderate-intensity exercise. We investigated whether consuming protein plus carbohydrate (PRO) immediately after an acute bout of aerobic exercise has an additive effect over carbohydrate alone (CHO) on WBPT in older individuals. Twelve healthy older adults (age, 59 ± 4 years) were studied on 2 separate occasions after 1 h of exercise at approximately 50% of maximal rate of oxygen uptake, followed by 4 h of recovery. Immediately following exercise, subjects ingested a CHO (60 g) or an isocaloric PRO beverage (40 g carbohydrate, 20 g whey protein). Whole-body protein metabolism was determined using [1-13C]leucine infusion (60 mg prime; 75 mgh(-1) continuous), and sampling blood and expired breath. Rates of whole-body leucine appearance and oxidation, and nonoxidative leucine disposal during the third and fourth hours of postexercise recovery were higher in the PRO group (2.51 ± 0.55, 0.78 ± 0.37, and 1.71 ± 0.44 micromol kg(-1)·min(-1), respectively) than in the CHO group (1.81 ± 0.27, 0.33 ± 0.14, and 1.47 ± 0.25 micromol kg(-1)·min-1, respectively; p = 0.001). Our results indicate that consumption of a PRO beverage after aerobic exercise increased WBPT to a greater extent than a CHO beverage.