Physical Activity and Sedentary Behavior Timing in Fatigued and Nonfatigued Adults With Multiple Sclerosis.

OBJECTIVE: To examine device-measured physical activity levels and sedentary behavior participation during different times of the day (ie, morning, midday, and evening) in adults with multiple sclerosis (MS) who differed in fatigue status. DESIGN: Cross-sectional survey. SETTING: Remote survey study managed by a university-based research laboratory. PARTICIPANTS: A population-based sample of 1000 participants with MS were sent recruitment materials by the North American Research Committee on Multiple Sclerosis and 218 participants completed all relevant outcomes (N=218). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Participants (N=218) completed the Fatigue Severity Scale (FSS) as a measure of fatigue severity and were divided into subgroups of fatigued (FSS score ≥4) and nonfatigued (FSS score <4). Participants wore an ActiGraph GT3X+ on the nondominant hip for 7 days to measure physical activity (ie, light physical activity [LPA], moderate-to-vigorous physical activity [MVPA], steps) and sedentary behavior. RESULTS: Fatigued participants engaged in less MVPA (F[1216]=18.5, P<.001), fewer steps (F[1216]=27.8, P<.001), and more sedentary time (F[1216]=8.2, P=.005) than nonfatigued participants. Regardless of group, the highest levels of LPA (F[1.7355.7]=72.9, P<.001) and MVPA (F[1.8395.3]=23.0,P<.001) occurred in the morning and middle of the day, with the lowest levels in the evening. Regardless of group, the highest levels of sedentary behavior occurred in the evening, with similar levels in the morning and evening (F[1.6354.5]=84.3,P<.001). Regardless of group, participants had more steps in the middle of the day, followed by morning and then evening (F[1.8383.9]=84.7,P<.001). CONCLUSIONS: Our results suggest that physical activity timing should be considered in future development and delivery of behavior interventions that focus on increasing physical activity and reducing sedentary behavior among adults with MS who have fatigue.

Restless legs syndrome and health-related quality of life in adults with multiple sclerosis.

Restless legs syndrome (RLS) is a sleep disorder that may exacerbate many of the symptoms and consequences of multiple sclerosis (MS), and may have further implications for health-related quality of life (HRQOL). The present study examined the relationships among RLS, symptoms and HRQOL in people with MS. Participants with MS (n = 275) completed the Cambridge-Hopkins Restless Legs Syndrome Questionnaire, the International Restless Legs Syndrome Study Group Scale, the Multiple Sclerosis Impact Scale, the Pittsburgh Sleep Quality Index, the Fatigue Severity Scale, the Hospital Anxiety and Depression Scale and the Patient Determined Disease Steps. There were 74 (26.9%) persons with MS who had RLS (MS + RLS). The MS + RLS group reported worse physical and psychological HRQOL (p = 0.020 and p = 0.017, respectively) and greater perceived fatigue (p = 0.006) and anxiety symptoms (p = 0.042) than the MS-only group. Within the MS + RLS group, RLS severity was associated with physical (r = 0.43) and psychological (r = 0.46) HRQOL, sleep quality (r = 0.38), perceived fatigue (r = 0.28), depression (r = 0.38) and anxiety (r = 0.28). The relationships between RLS severity and the domains of HRQOL were attenuated when accounting for fatigue, depression and/or anxiety. Worse RLS severity was associated with reduced HRQOL, which was accounted for by fatigue, depression and anxiety.

Step-rate threshold for physical activity intensity in Parkinson's disease.

OBJECTIVES: To examine the relationship between step-rate and energy expenditure during treadmill walking in persons with PD and then further develop a step-rate cut-point for moderate-to-vigorous physical activity (MVPA) for persons with PD. MATERIALS AND METHODS: The sample consisted of 30 persons with mild-to-moderate PD and 30 controls matched by age and sex. Participants performed a 6-minute bout of over-ground walking at comfortable speed, and then completed three, 6-minute bouts of treadmill walking at 13.4 m/min slower, comfortable, and 13.4 m/min faster than comfortable speeds. The three treadmill speeds were based on the initial over-ground walking speed. The total number of steps per treadmill walking bout was recorded using a hand-tally counter, and energy expenditure was measured using a portable, indirect spirometry system. RESULTS: The results indicated a strong association between step-rate and energy expenditure for persons with PD (R2  = .92) and controls (R2  = .92). The analyses further indicated a steeper slope of the association for persons with PD compared with controls (t(58) = -1.87, P < .05), resulting in a lower step-rate threshold (t(58) = 2.19, P < .05) for persons with PD (~80 steps·per minutes) than controls (~93 steps·per minutes). CONCLUSION: Collectively, these results support the application of this disease-specific step-rate threshold for MVPA among persons with PD. This has important implications for physical activity promotion, prescription, and monitoring using accelerometers and pedometers for persons with PD to manage health and symptoms of PD.

Changes in Cognitive Performance With Age in Adults With Multiple Sclerosis.

BACKGROUND: Cognitive impairment is one of the most common consequences of multiple sclerosis (MS), yet there is a shortage of data regarding how cognition changes during the life span of individuals with MS. This information is of increasing importance given the growing proportion of older adults with MS. OBJECTIVE: To study possible changes in cognitive function in correlation with increasing age in individuals with MS. METHODS: Participants (N=129) were recruited and a priori allocated into one of three age groups (young, middle-aged, and older). All participants completed the Brief International Cognitive Assessment for Multiple Sclerosis (BICAMS) during a single laboratory testing session. The BICAMS measures cognitive processing speed as well as verbal and visuospatial learning and memory. RESULTS: A multivariate analysis of variance indicated that cognitive function significantly differed by age group, and these differences were not explained by amount of physical activity, years of education, years since diagnosis, or race. Older adults displayed significantly worse cognitive processing speed than young and middle-aged adults. The older and middle-aged adults also demonstrated significantly worse visuospatial learning and memory than the younger adults. Effect sizes indicated that cognitive processing speed and verbal learning and memory were more affected in late adulthood than early adulthood, whereas visuospatial learning and memory was affected similarly in early and late adulthood. CONCLUSIONS: Older adults with MS demonstrated significant impairments in cognitive function compared to young and middle-aged adults with MS. Future studies should determine the predictors of cognitive decline in this age cohort.

Physical activity classification with dynamic discriminative methods.

A person's physical activity has important health implications, so it is important to be able to measure aspects of physical activity objectively. One approach to doing that is to use data from an accelerometer to classify physical activity according to activity type (e.g., lying down, sitting, standing, or walking) or intensity (e.g., sedentary, light, moderate, or vigorous). This can be formulated as a labeled classification problem, where the model relates a feature vector summarizing the accelerometer signal in a window of time to the activity type or intensity in that window. These data exhibit two key characteristics: (1) the activity classes in different time windows are not independent, and (2) the accelerometer features have moderately high dimension and follow complex distributions. Through a simulation study and applications to three datasets, we demonstrate that a model's classification performance is related to how it addresses these aspects of the data. Dynamic methods that account for temporal dependence achieve better performance than static methods that do not. Generative methods that explicitly model the distribution of the accelerometer signal features do not perform as well as methods that take a discriminative approach to establishing the relationship between the accelerometer signal and the activity class. Specifically, Conditional Random Fields consistently have better performance than commonly employed methods that ignore temporal dependence or attempt to model the accelerometer features.

Combined Associations of Physical Activity and Sedentary Behavior With Depressive Symptoms in Older Adults.

The aim of this study was to analyze the association of combined physical activity (PA)/sedentary behaviour (SB) with depressive symptoms (DS) in older adults. A cross-sectional study was conducted with 622 individuals ≥ 60 years old. After adjusting for gender, years of study, and monthly household income, prevalence ratios for presence of DS were statistically significant for older adults with <150 min/week in PA and ≥75th percentile of SB on weekdays (PR = 2.11,95%CI: 1.54-2.90) and on weekends (PR = 2.20,95%CI:1.57-3.09). Older adults who do not meet the PA guidelines and spend more time in SB on weekdays or weekend days are more likely to present with DS compared to those who meet the recommendations of PA and spend less time in SB during the day.

Wrist-based accelerometer cut-points for quantifying moderate-to-vigorous intensity physical activity in Parkinson's disease.

BACKGROUND: Persons with Parkinson's disease (PD) participate in low levels of physical activity. This has prompted interest in developing interventions targeting physical activity behavior in PD. However, the current cut-points to quantify moderate-to-vigorous physical activity (MVPA) developed for PD have been derived from a single, vertical axis using hip-worn accelerometers, and this cut-point may not be applicable for wrist-worn devices. Wrist-worn devices might improve accessibility and compliance with physical activity monitoring in PD. RESEARCH QUESTION: What is the relationship between wrist-based activity counts and energy expenditure during treadmill walking in persons with PD? Do cut-points for quantifying time spent in MVPA differ between persons with PD and controls matched by age and sex? METHODS: The sample included 26 persons with mild-to-moderate PD (Hoehn and Yahr stages 2-3) and 27 age- and sex-matched controls. Participants completed three, 6-minute bouts of walking on a treadmill at three increasing speeds. Vector magnitude was measured using ActiGraph GT3X+ accelerometer worn on the more affected side for persons with PD and the non-dominant side for controls. The rate of oxygen consumption, or energy expenditure, was measured using a portable, open-circuit spirometry system. RESULTS: Our results indicated a strong association between activity counts and energy expenditure for persons with PD and controls with R2 values of 0.94(0.07) and 0.95(0.06), respectively. Persons with PD had a cut-point of 2883(871) counts·min-1; this was significantly lower than the cut-point of 4389(1844) counts·min-1 for controls. CONCLUSION: We generated a PD-specific cut-point for wrist-worn ActiGraph accelerometers among persons with PD, and this was lower than controls. This disease-specific cut-point may provide more accurate measurements of time spent in MVPA in PD.

Does physical activity timing differentially correlate with symptoms of restless legs syndrome in adults with multiple sclerosis?

OBJECTIVE/BACKGROUND: The present study examined the associations among physical activity during different times of the day(i.e., morning, midday,evening) and days of the week(i.e., weekdays, weekend days) with restless legs syndrome(RLS) severity and sleep quality in adults with multiple sclerosis(MS). PATIENTS/METHODS: Participants(N = 39) completed the International Restless Legs Syndrome Study Group Scale and the Pittsburgh Sleep Quality Index as measures of RLS severity and global sleep quality, respectively, and wore an ActiGraph GT3X + on the non-dominant hip for seven days for measuring physical activity(i.e., light physical activity[LPA], moderate-to-vigorous physical activity[MVPA], and steps). RESULTS: There was a significant effect of time of day wherein participants had more midday activity compared with morning or evening for LPA, MVPA, and steps; there was no effect of day of the week. Spearman's rho correlations across the week indicated higher evening LPA, evening steps, and overall daily steps (ρ = -0.42,ρ = -0.51,ρ = -0.40,respectively) were associated with lower RLS severity. Similar associations were demonstrated for weekdays(ρ = -0.39,ρ = -0.50,ρ = -0.41,respectively) and weekend days(ρ = -0.44,ρ = -0.51,ρ = -0.39,respectively). Higher evening MVPA on weekend days(ρ = -0.42) was associated with lower RLS severity. Higher morning and overall daily LPA(ρ = 0.34,ρ = 0.33,respecitvely) were associated with worse sleep quality. Similar associations were demonstrated on weekdays(ρ = 0.33,ρ = 0.37,respectively) and more evening MVPA(ρ = 0.32) was associated with worse sleep quality. On weekend days, more morning MVPA(ρ = 0.42) was associated with worse sleep quality. CONCLUSIONS: Our results suggest that undertaking physical activity, particularly LPA and steps, in evenings may be important for managing symptoms of RLS without worsening sleep quality.

Social Cognitive Theory variables as correlates of physical activity in fatigued persons with multiple sclerosis.

BACKGROUND: There is interest in the application of behavioral interventions based on theory for increasing physical activity among adults with multiple sclerosis (MS). To date, researchers have applied theory such as Social Cognitive Theory (SCT) for identifying correlates of physical activity that can then inform the design and delivery of behavioral interventions. Such research often has been conducted in heterogeneous samples of persons with MS without a focus on those with a specific symptom, such as fatigue, that may be targeted by physical activity behavioral interventions. To that end, this study examined SCT variables (i.e., self-efficacy, barriers, outcome expectations, goal-setting, planning, social support, and functional limitations) as correlates of physical activity in persons with MS who self-reported elevated fatigue. METHODS: Persons with MS (N=210; aged 49.6[13.2] years) who ambulated with or without assistance participated in the study. Participants completed self-report measures of fatigue, physical activity, and SCT variables and wore an ActiGraph GT3X+ accelerometer on a belt around the waist for 7 days. The accelerometer data were processed and delineated into time spent in light and moderate-to-vigorous physical activity (MVPA) based on MS-specific cut-points. We generated groups of fatigued (n=134) and non-fatigued (n=76) persons with MS based on the cut-off score of 4 for the Fatigue Severity Scale. RESULTS: There were differences in physical activity and SCT variables between fatigued and non-fatigued persons with MS. Among those with fatigue, functional limitations (ρ=0.52), self-efficacy (ρ=0.31), and goal-setting (ρ=0.25) were associated with device-measured MVPA, and all SCT variables except outcome expectations were associated with self-reported physical activity. The regression analyses indicated self-efficacy, functional limitations, and goal-setting as significant correlates of MVPA in those with fatigue. CONCLUSION: Self-efficacy, goal-setting, and social support may be important targets of SCT-based behavioral interventions for increasing physical activity among persons with MS who have fatigue.

Can Sports Practice in Childhood and Adolescence Be Associated with Higher Intensities of Physical Activity in Adult Life? A Retrospective Study in Community-Dwelling Adults.

INTRODUCTION: Investigating the determinants of physical activity (PA) is an important strategy for the promotion of healthy lifestyles, mainly with PA of a moderate-to-vigorous intensity, which provides several health benefits in adulthood. In this sense, it is not clear whether early sports practice (ESP) during childhood and adolescence could be associated with the habitual practice of PA of higher intensities in adulthood. OBJECTIVE: This study aimed to analyze the association of ESP in childhood and adolescence with different intensities of habitual PA in adulthood. METHODS: A sample of 264 community-dwelling adults were randomly selected (42.2 ± 17.0 years, 57.5% of women). ESP during childhood and adolescence was evaluated using retrospective questions. Weekly minutes of PA were assessed using accelerometry and classified according to intensity as light, moderate, moderate-to-vigorous, vigorous and very vigorous. The association of ESP with a high level of PA (above median) in each intensity was analyzed using binary regression models. RESULTS: The prevalence of ESP was 42.8% in childhood and 49.2% in adolescence. ESP in childhood was associated with a high level of very vigorous (OR: 2.48, p < 0.001) and vigorous PA (OR: 2.91, p < 0.001) in adulthood, but lost significance after adjustments by sex and age. ESP in adolescence was associated with a high level of very vigorous PA (OR: 1.99, p = 0.013) in the crude model and vigorous PA (OR: 2.21, p = 0.006), even after adjustments by age, sex and socioeconomic status. CONCLUSIONS: Engagement in sports practice during adolescence was associated with high levels of vigorous PA in adulthood and is an important period for healthy lifestyle promotion.

Physical activity, cardiorespiratory fitness, and metabolic syndrome in adolescents: a cross-sectional study.

BACKGROUND: In adults, there is a substantial body of evidence that physical inactivity or low cardiorespiratory fitness levels are strongly associated with the development of metabolic syndrome. Although this association has been studied extensively in adults, little is known regarding this association in adolescents. The aim of this study was to analyze the association between physical activity and cardiorespiratory fitness levels with metabolic syndrome in Brazilian adolescents. METHODS: A random sample of 223 girls (mean age, 14.4 ± 1.6 years) and 233 boys (mean age, 14.6 ± 1.6 years) was selected for the study. The level of physical activity was determined by the Bouchard three-day physical activity record. Cardiorespiratory fitness was estimated by the Leger 20-meter shuttle run test. The metabolic syndrome components assessed included waist circumference, blood pressure, HDL-cholesterol, triglycerides, and fasting plasma glucose levels. Independent Student t-tests were used to assess gender differences. The associations between physical activity and cardiorespiratory fitness with the presence of metabolic syndrome were calculated using logistic regression models adjusted for age and gender. RESULTS: A high prevalence of metabolic syndrome was observed in inactive adolescents (males, 11.4%; females, 7.2%) and adolescents with low cardiorespiratory fitness levels (males, 13.9%; females, 8.6%). A significant relationship existed between metabolic syndrome and low cardiorespiratory fitness (OR, 3.0 [1.13-7.94]). CONCLUSION: The prevalence of metabolic syndrome is high among adolescents who are inactive and those with low cardiorespiratory fitness. Prevention strategies for metabolic syndrome should concentrate on enhancing fitness levels early in life.

Sociodemographic and clinical correlates of device-measured sedentary behaviour in multiple sclerosis.

PURPOSE: This study examined sociodemographic and clinical variables as correlates of device-measured volume and pattern of sedentary behaviour in persons with multiple sclerosis (MS). MATERIALS AND METHODS: Participants were recruited through a standardised invitation letter distributed among 1000 persons randomly selected from the North American Research Committee on MS registry. Those who volunteered wore an accelerometer for 7 d and provided sociodemographic and clinical information. RESULTS: There were 233 persons with MS who were included in the analyses. Linear regression analyses indicated that age and MS type explained significant variance in total sedentary time per day as well as number of breaks in sedentary time. Only disability status explained significant variance in sedentary bout length, whereas age explained significant variance in both number of long sedentary bouts per day. Both age and disability status explained significant variance total time spent in long sedentary bouts per day. CONCLUSIONS: Persons of older age, progressive MS, and higher disability status spend prolonged, uninterrupted periods of time sedentary. Such results highlight the need for targeted interventions in sub-populations of MS that reduce time spent sedentary and break up the pattern of sedentary behaviour. Implications for Rehabilitation Sedentary behaviour is highly prevalent in multiple sclerosis and may be associated with comorbid conditions. The majority of research on sedentary behaviour in multiple sclerosis has been derived from self-report instruments that only measure the volume of sitting time per day. This study indicates that persons with multiple sclerosis spend a significant amount of time sedentary, and those who are older, have progressive multiple sclerosis, and have higher disability status spend prolonged, uninterrupted periods of time sedentary. Such results highlight the need for targeted behavioural interventions in these sub-populations of multiple sclerosis to reduce time spent sedentary and break the pattern of sedentary behaviour to manage its consequences.

Accuracy and precision of wrist-worn actigraphy for measuring steps taken during over-ground and treadmill walking in adults with Parkinson's disease.

INTRODUCTION: Step counts represent a straight-forward method of measuring physical activity in adults with Parkinson's disease (PD). The present study examined the absolute and relative accuracy and precision of a wrist-worn research-grade accelerometer (i.e., ActiGraph GT3X+) for measuring step counts during over-ground and treadmill walking in adults with PD and controls without PD. METHODS: Participants (PD: n = 29; controls: n = 31) wore two ActiGraph GT3X + accelerometers, one on each wrist, and completed an over-ground walking bout followed by a treadmill walking bout at the same speed. Step counts were measured manually using a hand-held tally counter. Accuracy and precision were based on absolute and relative metrics. RESULTS: The ActiGraph GT3X + underestimated step counts in both participants with PD (4.7-11% error) and controls without PD (8.8-17% error), with a greater discrepancy in controls. The ActiGraph GT3X + provided more accurate and precise estimates of step counts when placed on the more affected wrist and non-dominant wrist for participants with PD and controls, respectively, and was more accurate and precise during over-ground walking compared with treadmill walking for both groups. CONCLUSIONS: Our results suggest that placement of the device (i.e., dominant vs. non-dominant), type of activity (i.e., over-ground vs. treadmill walking), and presence of clinical conditions may impact the accuracy and precision of data when using the research-grade ActiGraph GT3X + accelerometer for measuring step counts.

Demographic, clinical, and symptomatic correlates of subjective sleep quality in adults with multiple sclerosis.

BACKGROUND: This study examined a comprehensive set of demographic, clinical, and symptomatic variables as correlates of subjective sleep quality in adults with multiple sclerosis (MS). METHODS: Participants with MS(N=485) completed the Pittsburgh Sleep Quality Index(PSQI), a demographics and clinical characteristics questionnaire, the Patient Determined Disease Steps Scale(PDDS), the Fatigue Severity Scale, and the Hospital Anxiety and Depression Scale. We conducted bivariate Spearman's rho (ρ) correlation analyses and multiple linear regression analysis for identifying variables associated with PSQI scores. RESULTS: Participants had a mean (standard deviation) age of 55.4 (12.6) years and were mostly female (78%) with a median [interquartile range] PDDS of 2.0[3.0]. Higher levels of fatigue (ρ=0.32), more symptoms of anxiety (ρ=0.39) and depression (ρ=0.36), younger age (ρ=-0.12), lower income status (ρ=-0.13), shorter MS disease duration (ρ=-0.11), being in a minority group (ρ=0.09), and being unemployed (ρ=-0.10) were associated with worse sleep quality. There were no significant associations between gender, marital status, parental status, education level, disability status, or MS disease type and sleep quality. The overall regression model accounted for 26.3% of variance in sleep quality (F[8,229.8]=20.25) and there were significant coefficients for anxiety(ß=0.25), fatigue(ß=0.18), depression(ß=0.16), and employment status(ß=-0.12), but not disease duration, age, race, or income level. DISCUSSION: Participants with higher levels of anxiety, fatigue, and depression and who were unemployed reported worse sleep quality in our sample of adults with MS. These results may identify specific subgroups of the MS population that experience more sleep problems, and therefore are in greatest need for interventions designed to improve sleep impairment.

Perceived injustice in multiple sclerosis: An initial, exploratory study.

PURPOSE/OBJECTIVE: The current study represents an initial examination of condition-related perceived injustice (PI) in multiple sclerosis (MS) by examining (a) the structural validity and reliability of the Injustice Experience Questionnaire (IEQ) scores and (b) the associations between IEQ scores and scores from measures of anger, pain, depression, anxiety, fatigue, disability, health-related quality of life (HRQOL), physical activity, and sedentary behavior. Research Method/Design: Persons with MS were recruited through the distribution of letters to a random sample of 1,000 persons from the North American Research Committee on MS registry. Participants who completed the IEQ (N = 139) were included in this analysis. RESULTS: Our results support the structural validity of the 2-factor model of Severity/Irreparability and Blame/Unfairness subscales with a Cronbach's alpha of .917 for the overall scale, and values of .857 and .889 for the subscales, respectively. All measures were meaningfully correlated with IEQ scores. Pain (ρ = .466), fatigue (ρ = .430), disability (ρ = .416), walking impairment (ρ = .446), and physical HRQOL (ρ = .624) were strongly correlated with Severity/Irreparability. Anger; however, was strongly correlated with Blame/Unfairness (ρ = .437). Physical activity and sedentary behavior were similarly correlated with the 2 subscales; however, both moderate-to-vigorous (ρ = -.332) and light physical activity (ρ = -.275) were slightly more correlated with Severity/Irreparability. CONCLUSIONS/IMPLICATIONS: The IEQ is a reliable and valid measure of PI in MS. Physical manifestations of MS are primarily associated with PI, and negative associations were observed between physical activity and IEQ scores. Physical activity may increase self-efficacy and counteract cognitions of permanent disability and frustration concerning limitations that are associated with PI. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Physical activity and self-reported sleep quality in adults with multiple sclerosis.

BACKGROUND: There is a fourfold higher prevalence of sleep problems in multiple sclerosis (MS) than the general population. OBJECTIVE: This study examined cross-sectional associations among device-measured sedentary and physical activity behavior with perceived sleep quality in adults with MS. METHODS: Adults with MS (N = 290) completed the Pittsburgh Sleep Quality Index (PSQI) and wore an accelerometer for seven days providing a measure of time spent in sedentary behavior, light physical activity (LPA), and moderate-to-vigorous physical activity (MVPA) using MS-specific cut-points. We conducted multiple linear regression analysis to identify the independent contributions of variables for explaining PSQI scores. RESULTS: The overall model accounted for 2% of the variance in global PSQI scores, and MVPA was significantly and independently associated with global PSQI scores (ß = â”€0.123; p = 0.045; partial r = â”€0.118) when accounting for average wear time, sedentary behavior, and time spent in LPA. There were no other significant associations with PSQI global score. CONCLUSIONS: Our results suggest that time spent in MVPA may be associated with better sleep quality in adults with MS, but adults with MS do not spend sufficient time in physical activity. Researchers should evaluate these relationships in longitudinal study designs and behavior change interventions, as physical activity may provide a unique opportunity to improve sleep quality outcomes.

Is Symptomatic Fatigue Associated With Physical Activity and Sedentary Behaviors Among Persons With Multiple Sclerosis?

Background. Fatigue is a debilitating symptom in multiple sclerosis (MS) that may be associated with reduced physical activity and increased sedentary behavior. Objective. This study examined the associations among fatigue and device-measured physical activity and sedentary behavior in people with MS. Methods. The participants (n = 252) completed the Patient Determined Disease Steps (PDDS) and Fatigue Severity Scale (FSS) and wore a waist-mounted accelerometer for 7 days. Participants were divided into 2 groups based on fatigue severity as measured by the FSS scale. We compared percentage of wear time spent in sedentary, light physical activity (LPA), and moderate to vigorous physical activity (MVPA) between the 2 groups. Results. Persons in the fatigued group (FSS score ≥ 4) spent a greater percentage of time in sedentary behavior (P = .004) and a lower percentage of time in LPA (P = .035). Persons in the fatigued group further spent a lower percentage of time in nontransformed MVPA (P < .001) and square-root-transformed MVPA (P < .001) than persons in the nonfatigued group. When controlling for PDDS scores and years of education, there were no longer significant differences between groups in sedentary behavior, LPA, or transformed MVPA values; the difference in nontransformed MVPA was still statistically significant but likely the result of nonnormally distributed data. Conclusion. The present study suggests that factors other than fatigue might be associated with physical activity and sedentary behavior in MS, and this group might benefit from focal behavioral interventions that take into account mobility status in persons with MS who have fatigue.

Restless legs syndrome, sleep quality, and perceived cognitive impairment in adults with multiple sclerosis.

BACKGROUND: Restless Legs Syndrome (RLS) is a prominent sleep disorder that often worsens sleep quality and perhaps cognitive function in adults with multiple sclerosis (MS). The present study examined the relationships among RLS prevalence and severity, sleep quality, and perceived cognitive impairment in adults with MS. METHODS: Participants (N=275) completed the Cambridge-Hopkins Restless Legs Syndrome Questionnaire, the International Restless Legs Syndrome Study Group (IRLS) Scale, the Multiple Sclerosis Neuropsychological Screening Questionnaire (MSNQ), the Pittsburgh Sleep Quality Index (PSQI), the Patient Determined Disease Steps (PDDS), and a demographic and clinical characteristics questionnaire. RESULTS: Persons with MS who had RLS (i.e., MS+RLS; n=74) reported significantly worse perceived cognitive impairment compared with those who did not have RLS (n=201; p=0.015). Bivariate correlation analyses within the MS+RLS group indicated that greater RLS severity was significantly associated with more severe perceived cognitive impairment (r=0.274) and sleep quality (r=0.380), and worse perceived cognitive impairment was significantly associated with worse sleep quality (r=0.438). Linear, step-wise regression analyses indicated that RLS severity significantly predicted perceived cognitive impairment (ß=0.274), but the inclusion of sleep quality (ß=0.391) accounted for the relationship between RLS severity and perceived cognitive impairment (ß=0.126). CONCLUSIONS: Our results suggest that sleep impairment may be an intermediary factor in the association between RLS severity and cognitive impairment in persons with MS who present with RLS. The diagnosis and treatment of RLS symptoms and other effectors of sleep quality could improve neuropsychological consequences of MS.

Accelerometer output and its association with energy expenditure in persons with mild-to-moderate Parkinson's disease.

OBJECTIVE: This study examined the association between ActiGraph accelerometer output and energy expenditure across different speeds of walking in persons with Parkinson's disease (PD), and further generated cut-points that represent a metric for quantifying time spent in moderate-to-vigorous physical activity (MVPA) among persons with PD. METHODS: The sample included 30 persons with mild-to-moderate PD (Hoehn and Yahr stages 2-3) and 30 adults without PD matched by sex and age. All participants completed 5 minutes of quiet, seated rest and then underwent three, 6-minute bouts of walking on a treadmill at three different speeds relative to the individual's self-selected pace. Activity counts were measured using an ActiGraph accelerometer worn at the waist level on the least affected side for persons with PD and the dominant side for controls. The rate of oxygen consumption, or energy expenditure, was measured using a portable, open-circuit spirometry system. RESULTS: Our results indicated a strong association between activity counts and energy expenditure for persons with PD (R2 = 0.87) and controls (R2 = 0.89). However, the significant difference in slopes resulted in a lower cut-point of 1,354 counts·min-1 for persons with PD than the cut-point of 2,010 counts·min-1 for controls. CONCLUSION: Our results support the application of the disease-specific cut-point for quantifying the amount of time spent in MVPA using ActiGraph accelerometers among persons with mild-to-moderate PD. Such an application may provide accurate estimates of MVPA in this population, and better inform future research examining the possible determinants and consequences of physical activity as well as testing of interventions for changing MVPA in PD.

Feasibility of "Sit Less, Move More": An intervention for reducing sedentary behavior Among African Americans with MS.

BACKGROUND: Sedentary behavior is a major concern in multiple sclerosis, as it may accelerate disease progression and physical disability. This is especially concerning in African Americans, who present with greater neurological disability than Caucasians. OBJECTIVE: We conducted a feasibility trial on an intervention targeting sedentary behavior in African Americans with multiple sclerosis. METHODS: We examined the feasibility of the Sit Less, Move More program, a 12-week behavioral intervention that used text messaging along with theory-driven newsletters and behavioral coaching for managing sedentary behavior. We recruited ambulatory, inactive, African Americans with multiple sclerosis, and assessed feasibility on process, resource, management, and scientific outcomes. RESULTS: Of the 64 people initially contacted, 45 were assessed for eligibility, 31 were sent the informed consent document, and 30 returned a signed document and were included in the study. Study costs were US$7242.38. Personnel time to complete the study was 130 h. There was a small effect on both device-measured (d = -0.19) and self-reported (d = -0.39) sedentary behavior. CONCLUSIONS: The Sit Less, Move More intervention is safe and feasible for African Americans with multiple sclerosis, and yielded a small reduction in sedentary behavior. The intervention was low cost and well received. Our results suggest the Sit Less, Move More program should progress towards a Phase II trial to determine its efficacy.