Effects of a DVD-Delivered Exercise Intervention on Maintenance of Physical Activity in Older Adults.

BACKGROUND: Previous research supports the efficacy of a 6-month DVD-delivered program for enhancing physical activity (PA) in older adults. In the current study, we examined the degree to which intervention-related increases in PA were maintained after a 6-month, no-contact follow-up. METHODS: Follow-up assessments of PA via accelerometry and the Godin Leisure-Time Exercise Questionnaire (GLTEQ) were collected in a sample of older adults (N = 238). Repeated measures analyses of variance were conducted to examine changes in PA over the course of the follow-up period. RESULTS: For accelerometer measured PA, there was a significant time × treatment × age group interaction, F1,203 =11.319, P = .001, η2 = .053, such that younger (≤70 years) intervention participants maintained high levels of PA across the follow-up period, while PA in older intervention and young control participants declined significantly. Rates of PA in older control participants remained low over the course of the follow-up period. Analyses of GLTEQ scores revealed similar, though less significant patterns. CONCLUSIONS: DVD-based exercise programs may be effective for maintaining PA in younger members of the older adult population; however, there remains a need to develop better strategies for promoting PA maintenance in older individuals when using home-based designs.

Preliminary validation of the short physical performance battery in older adults with multiple sclerosis: secondary data analysis.

BACKGROUND: There are relatively few standard, objective measures for studying physical function among older adults with multiple sclerosis (MS), yet such measures are necessary considering the shift in prevalence and associated consequences of both MS and older age on physical function. We undertook a preliminary examination of the construct validity of Short Physical Performance Battery (SPPB) scores in older adults with MS based on an expected differential pattern of associations with measures of lower and upper extremity function. METHODS: The sample included 48 persons with MS aged 50 years and older who were enrolled in a pilot, randomized controlled trial of exercise training. Participants completed the SPPB and other objective and self-report measures of lower and upper extremity function as part of baseline testing. RESULTS: SPPB scores demonstrated strong associations with measures of lower extremity function (|r s| = .66-.79), and weak associations with measures of upper extremity function (|r s| = .03-.33). CONCLUSIONS: We provide preliminary evidence that supports the validity of scores from the SPPB as a measure of lower extremity function for inclusion in clinical research and practice involving older adults with MS.

Effects of a DVD-delivered exercise intervention on physical function in older adults with multiple sclerosis: A pilot randomized controlled trial.

BACKGROUND: Older adults with multiple sclerosis (MS) exhibit disease-related impairments such as compromised strength, balance, mobility, coordination, and quality of life (QOL). Exercise training as an intervention to reverse these conditions in older adults with MS is limited. OBJECTIVE: The objective of this pilot trial was to examine the effects of a DVD exercise intervention targeting flexibility, strength, and balance in older adults with MS in order to generate effect sizes to power a larger trial. METHODS: Participants were randomly assigned to a six-month DVD exercise intervention (n = 24) or a healthy aging DVD control condition (n = 24). Measures of physical function, physical activity, sedentary behavior, QOL and program satisfaction were assessed at baseline and at follow-up. RESULTS: The DVD exercise intervention was well received with no adverse events. Effects sizes ranged from small to modest reflecting improved function, increased physical activity, decreased sitting time, and improved QOL in the intervention condition compared to the control condition. CONCLUSION: This pilot randomized controlled trial suggests that older adults with MS are receptive to an exercise program via DVD, and the program results in modest but potentially important improvements in function and physical activity.

Differential exercise effects on quality of life and health-related quality of life in older adults: a randomized controlled trial.

PURPOSE: Maintaining quality of life (QOL) and physical and mental health status are important outcomes throughout the aging process. Although cross-sectional studies suggest a relationship between global QOL and physical activity, it is unclear whether such a relationship exists as a function of exercise training. METHODS: We examined the effects of two exercise intervention arms on health-related quality of life (HRQOL) and global QOL. Low-active, older adults (n = 179) were randomly assigned to either a 12-month aerobic walking group or a strengthening and flexibility group. HRQOL and QOL were measured at baseline, 6, and 12 months. RESULTS: There was a significant group by time effect on QOL [F(2,176) = 3.11, p = 0.047, η (2) = 0.03]. There was also a significant overall group by time effect for HRQOL [F(4,174) = 2.46, p = 0.047, η (2) = 0.05], which was explained by the significant group by time interaction for mental health status (p = 0.041, η (2) = 0.02) favoring the walking condition. Further analyses using latent class analysis revealed three classes of individuals with differential patterns of change in QOL and HRQOL across time. These classes reflected no change, declines, and improvements in these constructs across time. CONCLUSIONS: Walking appears to enhance the mental aspect of HRQOL and global QOL when compared to a non-aerobic intervention. Additionally, the patterns of change in QOL and HRQOL were not linear over time. Our findings are in contrast to previous reports that these outcomes change a little or not at all in randomized trials.

Maintenance Effects of a DVD-Delivered Exercise Intervention on Physical Function in Older Adults.

BACKGROUND: Exercise training has been demonstrated to enhance physical function and to have a protective effect against functional limitations and disability in older adults. PURPOSE: The objective of this study was to determine whether the effects of a home-based, DVD-delivered exercise intervention on functional performance and limitations were maintained 6-month postintervention termination. METHODS: Follow-up assessments of functional performance and limitations were conducted in a sample of community-dwelling older adults (N = 237) who participated in a 6-month randomized controlled exercise trial. Participants were initially randomized to a DVD-delivered exercise intervention or an attentional control condition. The Short Physical Performance Battery, measures of flexibility and strength, and functional limitations were assessed immediately before and after the intervention and then again 6 months later. Analyses of covariance were conducted to examine changes in physical function between the two conditions at the end of the intervention to 6-month follow-up. RESULTS: There were statistically significant adjusted group differences in the Short Physical Performance Battery (η(2) = 0.03, p = .01), upper-body strength (η(2) = 0.03, p = .005), and lower-body flexibility (η(2) = 0.02, p = .05), indicating that gains brought about by the intervention were maintained 6 months later. CONCLUSIONS: A DVD-delivered exercise program specifically designed to target elements of functional fitness in older adults can produce clinically meaningful gains in physical function that are maintained beyond intervention cessation.

Physical activity levels and patterns in older adults: the influence of a DVD-based exercise program.

The use of multimedia to influence health behaviors offers unique advantages over more traditional center-based programs, however, little is known about the effectiveness of such approaches in improving physical activity levels over time. The purpose of this study was to examine the efficacy of a progressive and age-appropriate, DVD-delivered exercise program in promoting physical activity levels among older adult cohorts. Community dwelling older adults (N = 307, Mean age = 71 years) were randomized to one of two groups: a 6-month home-based DVD-delivered exercise (i.e., FlexToBa™) intervention group or a healthy aging DVD control group. Physical activity was assessed objectively using a standard 7-day accelerometer wear period and subjectively using the Godin Leisure Time Exercise Questionnaire, at baseline and follow-up. Analysis of covariances indicated a statistically significant treatment effect for subjectively [F(1,250) = 8.42, P = .004, η(2) = .03] and objectively [F(1,240) = 3.77, P = .05, η(2) = .02] measured physical activity. The older cohort (>70) in the FlexToBa condition further had significantly larger improvements in physical activity levels compared to their younger counterparts. From a public health perspective, media-delivered interventions such as the FlexToBa program might prove to be cost-effective, have a broader reach and at the same time be effective in improving physical activity levels in older adults.

Improving physical functional and quality of life in older adults with multiple sclerosis via a DVD-delivered exercise intervention: a study protocol.

INTRODUCTION: There is a need to identify innovative, low-cost and broad-reaching strategies for promoting exercise and improving physical function in older adults with multiple sclerosis (MS). METHODS AND ANALYSIS: This randomised controlled pilot trial will test the efficacy of a 6-month, DVD-delivered exercise intervention to improve functional performance and quality of life in older adults with MS. Participants will be randomised either into a DVD-delivered exercise condition or an attentional control condition. This novel approach to programme delivery provides participants with detailed exercise instructions which are presented in a progressive manner and includes a variety of modifications to better meet varying levels of physical abilities. The targeted exercises focus on three critical elements of functional fitness: flexibility, strength and balance. It is hypothesised that participants who are randomised to the exercise DVD condition will demonstrate improvements in physical function compared with participants assigned to the attentional control condition. Data analysis will include a 2 (condition)×2 (time) mixed factor analysis of variance (ANOVA) that follows intent-to-treat principles, as well as an examination of effect sizes. Participants will take part in qualitative interviews about perspectives on physical activity and programme participation. ETHICS AND DISSEMINATION: The study protocol was approved by a university institutional review board and registered with a federal database. Participants will be asked to read and sign a detailed informed consent document and will be required to provide a physician's approval to participate in the study. The exercise DVDs include an overview of safety-related concerns and recommendations relative to exercise participation, as well as detailed instructions highlighting the proper execution of each exercise presented on screen. Following completion of this trial, data will be immediately analysed and results will be presented at scientific meetings and published in scholarly journals. TRIAL REGISTRATION NUMBER: Clinical Trials NCT01993095.

II. Physical activity: measurement and behavioral patterns in children and youth.

With physical activity levels among children and adolescents at an all-time low, there is a critical need for scientists and public health officials alike to further examine the physical activity behaviors of this population. Accordingly, this chapter will act as an entrée to the rest of the monograph by providing a general overview of the epidemiology of physical activity among youth in the United States. In so doing, we discuss the following: public health guidelines for youth-based physical activity, current rates and trends of physical activity participation in youth, issues related to physical education rates in school systems, lifestyle practices that encourage sedentary behaviors and attendant disease states, a synopsis of the health-related benefits of a physically active lifestyle, promotion of and opportunities for increased engagement, and comparisons of objective and subjective methods of measuring physical activity.

Promoting Physical Activity in Low-Active Adolescents via Facebook: A Pilot Randomized Controlled Trial to Test Feasibility.

BACKGROUND: The World Wide Web is an effective method for delivering health behavior programs, yet major limitations remain (eg, cost of development, time and resource requirements, limited interactivity). Social media, however, has the potential to deliver highly customizable and socially interactive behavioral interventions with fewer constraints. Thus, the evaluation of social media as a means to influence health behaviors is warranted. OBJECTIVE: The objective of this trial was to examine and demonstrate the feasibility of using an established social networking platform (ie, Facebook) to deliver an 8 week physical activity intervention to a sample of low-active adolescents (N=21; estimated marginal mean age 13.48 years). METHODS: Participants were randomized to either an experimental (ie, Behavioral) or attentional control (ie, Informational) condition. Both conditions received access to a restricted-access, study-specific Facebook group where the group's administrator made two daily wall posts containing youth-based physical activity information and resources. Primary outcomes included physical activity as assessed by accelerometry and self-report. Interactions and main effects were examined, as well as mean differences in effect sizes. RESULTS: Analyses revealed significant improvements over time on subjectively reported weekly leisure-time physical activity (F1,18=8.426, P=.009, η2 = .319). However, there was no interaction between time and condition (F1,18=0.002, P=.968, η2 = .000). There were no significant time or interaction effects among the objectively measured physical activity variables. Examination of effect sizes revealed moderate-to-large changes in physical activity outcomes. CONCLUSIONS: Results provide initial support for the feasibility of delivery of a physical activity intervention to low-active adolescents via social media. Whether by employing behavioral interventions via social media can result in statistically meaningful changes in health-related behaviors and outcomes remains to be determined. TRIAL REGISTRATION: ClinicalTrials.gov NCT01870323; http://clinicaltrials.gov/show/NCT01870323 (Archived by WebCite at http://www.webcitation.org/6SUTmSeZZ).

Physical activity and cardiorespiratory fitness are beneficial for white matter in low-fit older adults.

Physical activity (PA) and cardiorespiratory fitness (CRF) are associated with better cognitive function in late life, but the neural correlates for these relationships are unclear. To study these correlates, we examined the association of both PA and CRF with measures of white matter (WM) integrity in 88 healthy low-fit adults (age 60-78). Using accelerometry, we objectively measured sedentary behavior, light PA, and moderate to vigorous PA (MV-PA) over a week. We showed that greater MV-PA was related to lower volume of WM lesions. The association between PA and WM microstructural integrity (measured with diffusion tensor imaging) was region-specific: light PA was related to temporal WM, while sedentary behavior was associated with lower integrity in the parahippocampal WM. Our findings highlight that engaging in PA of various intensity in parallel with avoiding sedentariness are important in maintaining WM health in older age, supporting public health recommendations that emphasize the importance of active lifestyle.

Executive function processes predict mobility outcomes in older adults.

OBJECTIVES: To examine the relationship between performance on executive function measures and subsequent mobility outcomes in community-dwelling older adults. DESIGN: Randomized controlled clinical trial. SETTING: Champaign-Urbana, Illinois. PARTICIPANTS: Community-dwelling older adults (N = 179; mean age 66.4). INTERVENTION: A 12-month exercise trial with two arms: an aerobic exercise group and a stretching and strengthening group. MEASUREMENTS: Established cognitive tests of executive function (flanker task, task switching, and a dual-task paradigm) and the Wisconsin card sort test. Mobility was assessed using the timed 8-foot up and go test and times to climb up and down a flight of stairs. METHODS: Participants completed the cognitive tests at baseline and the mobility measures at baseline and after 12 months of the intervention. Multiple regression analyses were conducted to determine whether baseline executive function predicted postintervention functional performance after controlling for age, sex, education, cardiorespiratory fitness, and baseline mobility levels. RESULTS: Selective baseline executive function measurements, particularly performance on the flanker task (ß = 0.15-0.17) and the Wisconsin card sort test (ß = 0.11-0.16) consistently predicted mobility outcomes at 12 months. The estimates were in the expected direction, such that better baseline performance on the executive function measures predicted better performance on the timed mobility tests independent of intervention. CONCLUSION: Executive functions of inhibitory control, mental set shifting, and attentional flexibility were predictive of functional mobility. Given the literature associating mobility limitations with disability, morbidity, and mortality, these results are important for understanding the antecedents to poor mobility function that well-designed interventions to improve cognitive performance can attenuate.

Influence of allowable interruption period on estimates of accelerometer wear time and sedentary time in older adults.

The criteria one uses to reduce accelerometer data can profoundly influence the interpretation of research outcomes. The purpose of this study was to examine the influence of 3 different interruption periods (i.e., 20, 30, and 60 min) on the amount of data retained for analyses and estimates of sedentary time among older adults. Older adults (N = 311, M age = 71.1) wore an accelerometer for 7 d and reported wear time on an accelerometer log. Accelerometer data were downloaded and scored using 20-, 30-, and 60-min interruption periods. Estimates of wear time, derived using each interruption period, were compared with self-reported wear time, and descriptive statistics were used to compare estimates of sedentary time. Results showed a longer interruption period (i.e., 60 min) yields the largest sample size and the closest approximation of self-reported wear time. A short interruption period (i.e., 20 min) is likely to underestimate sedentary time among older adults.

Effects of a DVD-delivered exercise intervention on physical function in older adults.

BACKGROUND: Given the rapidly increasing demographic of older adults, it is vital to implement effective behavioral strategies to improve physical function to maintain activities of daily living. However, changing physical activity in older adults remains extremely difficult. The current trial tested the efficacy of a novel, 6-month, home-based, DVD-delivered exercise program focusing on flexibility, balance, and toning on the physical function of older adults. METHODS: Older adults (N = 307) were recruited from 83 towns and cities throughout central Illinois. The trial consisted of 4 waves of recruitment and randomization from May 2010 through January 2012. Inclusion criteria included being inactive, at least 65 years of age, English speaking, providing physician's consent, and willingness to be randomized. Eligible participants were randomly assigned to 1 of 2 treatment conditions: the exercise intervention or a healthy aging, attentional control. Functional assessments were completed at baseline and following the 6-month DVD intervention. Measures included the Short Physical Performance Battery, assessments of flexibility and strength, and self-reported functional limitations. RESULTS: Participants in the DVD intervention condition demonstrated significant improvements in the Short Physical Performance Battery (p = .005), lower extremity flexibility (p = .04), and upper body strength (p = .003). There were no effects of the intervention on self-reported functional limitations. CONCLUSIONS: The exercise intervention produced a clinically significant improvement in the Short Physical Performance Battery and improvements in flexibility and strength, demonstrating the effectiveness of a low-cost DVD exercise program in improving physical function in older adults.

A profile for predicting attrition from exercise in older adults.

The purpose of this study was to determine a profile for predicting attrition among older adults involved in a 12-month exercise program. The parent study was a single-blinded randomized controlled trial. The study took place between 2006 and 2009 within a university setting. Older adults (N = 179) completed baseline assessments of functional performance and psychosocial measures. Participants who were randomized, elected to receive treatment, and did not complete the exercise program were considered "dropouts" (n = 35). Those who completed the program (n = 144) were classified as "completers." A latent profile analysis revealed two distinct patterns of memory complaints, self-efficacy to overcome barriers to exercise, balance performance, and stair performance. Dropouts were nearly twice as likely to be members of the profile that exhibited a higher degree of memory complaints, lower self-efficacy for overcoming exercise barriers, poorer single leg balance, and longer times to walk down stairs. The results provide an initial validation of a profile for discriminating between "dropouts" and "completers," one that may have considerable utility for screening older adults prior to study entry.

The influence of aerobic fitness on cerebral white matter integrity and cognitive function in older adults: results of a one-year exercise intervention.

Cerebral white matter (WM) degeneration occurs with increasing age and is associated with declining cognitive function. Research has shown that cardiorespiratory fitness and exercise are effective as protective, even restorative, agents against cognitive and neurobiological impairments in older adults. In this study, we investigated whether the beneficial impact of aerobic fitness would extend to WM integrity in the context of a one-year exercise intervention. Further, we examined the pattern of diffusivity changes to better understand the underlying biological mechanisms. Finally, we assessed whether training-induced changes in WM integrity would be associated with improvements in cognitive performance independent of aerobic fitness gains. Results showed that aerobic fitness training did not affect group-level change in WM integrity, executive function, or short-term memory, but that greater aerobic fitness derived from the walking program was associated with greater change in WM integrity in the frontal and temporal lobes, and greater improvement in short-term memory. Increases in WM integrity, however, were not associated with short-term memory improvement, independent of fitness improvements. Therefore, while not all findings are consistent with previous research, we provide novel evidence for correlated change in training-induced aerobic fitness, WM integrity, and cognition among healthy older adults.

The perceived importance of physical activity: associations with psychosocial and health-related outcomes.

BACKGROUND: The purpose of this study was to assess the extent to which participation in a 12-month exercise program changed the degree of importance that older adults attached to physical activity. In addition, associations among changes in physical activity importance and health-related and psychosocial outcomes were examined. METHODS: Community-dwelling older adults (N = 179) were recruited to participate in a 12-month exercise trial examining the association between changes in physical activity and fitness with changes in brain structure and psychological health. Participants were randomly assigned to a walking condition or a flexibility, toning, and balance condition. Physical, psychological, and cognitive assessments were taken at months 0, 6, and 12. RESULTS: Involvement in a 12-month exercise program increased the importance that participants placed on physical activity; this positive change was similar across exercise condition and sex. Changes in importance, however, were only associated with changes in physical health status and outcome expectations for exercise midway through the intervention. There were no significant associations at the end of the program. CONCLUSIONS: Regular participation in physical activity can positively influence the perceived importance of the behavior itself. Yet, the implications of such changes on physical activity-related outcomes remain equivocal and warrant further investigation.

Neurobiological markers of exercise-related brain plasticity in older adults.

The current study examined how a randomized one-year aerobic exercise program for healthy older adults would affect serum levels of brain-derived neurotrophic factor (BDNF), insulin-like growth factor type 1 (IGF-1), and vascular endothelial growth factor (VEGF) - putative markers of exercise-induced benefits on brain function. The study also examined whether (a) change in the concentration of these growth factors was associated with alterations in functional connectivity following exercise, and (b) the extent to which pre-intervention growth factor levels were associated with training-related changes in functional connectivity. In 65 participants (mean age=66.4), we found that although there were no group-level changes in growth factors as a function of the intervention, increased temporal lobe connectivity between the bilateral parahippocampus and the bilateral middle temporal gyrus was associated with increased BDNF, IGF-1, and VEGF for an aerobic walking group but not for a non-aerobic control group, and greater pre-intervention VEGF was associated with greater training-related increases in this functional connection. Results are consistent with animal models of exercise and the brain, but are the first to show in humans that exercise-induced increases in temporal lobe functional connectivity are associated with changes in growth factors and may be augmented by greater baseline VEGF.

Physical activity and quality of life in older adults: an 18-month panel analysis.

PURPOSE: Although physical activity has been associated with quality of life (QOL), the empirical evidence regarding the mechanisms underlying this relationship is limited. In the present study, we examined the mediating roles played by self-efficacy and health status in the physical activity-QOL relationship from baseline to 18-month follow-up in a sample of community-dwelling older adults. METHODS: Community-dwelling adults (N = 321, M age = 63.8 years) were recruited to participate in a cross-sectional study and were later contacted to participate in an 18-month follow-up. Individuals completed a battery of questionnaires assessing physical activity, self-efficacy, physical self-worth, disability limitations, and quality of life. A panel analysis within a covariance modeling framework was used to analyze the data. RESULTS: Overall, the model was a good fit to the data (χ(2) = 61.00, df = 29, p < 0.001, standardized root mean residual = 0.05, Comparative Fit Index = 0.97) with changes in physical activity indirectly influencing change in life satisfaction from baseline to 18 months via changes in exercise self-efficacy, physical self-worth, and disability limitations independent of baseline relationships and demographic factors. Specifically, increases in physical activity were associated with increases in exercise self-efficacy which, in turn, was associated with higher physical self-worth and fewer disability limitations which were associated with greater life satisfaction. CONCLUSIONS: The findings from this study suggest the relationship between physical activity and global QOL in older adults may be mediated by more proximal modifiable outcomes that can be targeted in physical activity programs and interventions.

Caudate Nucleus Volume Mediates the Link between Cardiorespiratory Fitness and Cognitive Flexibility in Older Adults.

The basal ganglia play a central role in regulating the response selection abilities that are critical for mental flexibility. In neocortical areas, higher cardiorespiratory fitness levels are associated with increased gray matter volume, and these volumetric differences mediate enhanced cognitive performance in a variety of tasks. Here we examine whether cardiorespiratory fitness correlates with the volume of the subcortical nuclei that make up the basal ganglia and whether this relationship predicts cognitive flexibility in older adults. Structural MRI was used to determine the volume of the basal ganglia nuclei in a group of older, neurologically healthy individuals (mean age 66 years, N = 179). Measures of cardiorespiratory fitness (VO(2max)), cognitive flexibility (task switching), and attentional control (flanker task) were also collected. Higher fitness levels were correlated with higher accuracy rates in the Task Switching paradigm. In addition, the volume of the caudate nucleus, putamen, and globus pallidus positively correlated with Task Switching accuracy. Nested regression modeling revealed that caudate nucleus volume was a significant mediator of the relationship between cardiorespiratory fitness, and task switching performance. These findings indicate that higher cardiorespiratory fitness predicts better cognitive flexibility in older adults through greater grey matter volume in the dorsal striatum.

Validity of the multidimensional outcome expectations for exercise scale in continuing-care retirement communities.

OBJECTIVE: The current study examined the psychometric properties and validity of the Multidimensional Outcome Expectations for Exercise Scale (MOEES) in a sample of older adults with physical and functional comorbidities. METHODS: Confirmatory factor analysis was used to examine the hypothesized 3-factor model in 108 older adults (M age 85 yr) residing in continuing-care retirement communities. RESULTS: Analyses supported the 3-factor structure of the MOEES reflecting physical, social, and self-evaluative outcome expectations, with a 12-item model providing the best fit. Theorized bivariate associations between outcome expectations and physical activity, self-efficacy, and functional performance were all supported. CONCLUSIONS: The 12-item version of the MOEES appears to be a reliable and valid measure of outcome expectations for exercise in this sample of older adults with physical and functional comorbidities. Further examination of the factor structure and the longitudinal properties of this measure in older adults is warranted.