Steps to Better Cardiovascular Health: How Many Steps Does It Take to Achieve Good Health and How Confident Are We in This Number?

Personalized digital behaviour interventions increase short-term physical activity: a randomized control crossover trial substudy of the MyHeart Counts Cardiovascular Health Study

Aims

Physical activity is associated with decreased incidence of the chronic diseases associated with aging. We previously demonstrated that digital interventions delivered through a smartphone app can increase short-term physical activity.

Methods and results

We offered enrolment to community-living iPhone-using adults aged ≥18 years in the USA, UK, and Hong Kong who downloaded the MyHeart Counts app. After completion of a 1-week baseline period, e-consented participants were randomized to four 7-day interventions. Interventions consisted of: (i) daily personalized e-coaching based on the individual's baseline activity patterns, (ii) daily prompts to complete 10 000 steps, (iii) hourly prompts to stand following inactivity, and (iv) daily instructions to read guidelines from the American Heart Association (AHA) website. After completion of one 7-day intervention, participants subsequently randomized to the next intervention of the crossover trial. The trial was completed in a free-living setting, where neither the participants nor investigators were blinded to the intervention. The primary outcome was change in mean daily step count from baseline for each of the four interventions, assessed in a modified intention-to-treat analysis (modified in that participants had to complete 7 days of baseline monitoring and at least 1 day of an intervention to be included in analyses). This trial is registered with ClinicalTrials.gov, NCT03090321.

Conclusion

Between 1 January 2017 and 1 April 2022, 4500 participants consented to enrol in the trial (a subset of the approximately 50 000 participants in the larger MyHeart Counts study), of whom 2458 completed 7 days of baseline monitoring (mean daily steps 4232 ± 73) and at least 1 day of one of the four interventions. Personalized e-coaching prompts, tailored to an individual based on their baseline activity, increased step count significantly (+402 ± 71 steps from baseline, P = 7.1⨯10-8). Hourly stand prompts (+292 steps from baseline, P = 0.00029) and a daily prompt to read AHA guidelines (+215 steps from baseline, P = 0.021) were significantly associated with increased mean daily step count, while a daily reminder to complete 10 000 steps was not (+170 steps from baseline, P = 0.11). Digital studies have a significant advantage over traditional clinical trials in that they can continuously recruit participants in a cost-effective manner, allowing for new insights provided by increased statistical power and refinement of prior signals. Here, we present a novel finding that digital interventions tailored to an individual are effective in increasing short-term physical activity in a free-living cohort. These data suggest that participants are more likely to react positively and increase their physical activity when prompts are personalized. Further studies are needed to determine the effects of digital interventions on long-term outcomes.

Physical activity of daily life of Bundeswehr soldiers: a cross-sectional study

INTRODUCTION

Activity of daily life is an important key to maintaining and improving the health status. This is especially important for people in physically demanding jobs, such as firefighters, military and police.

METHODS

In order to record the actual state of activity of daily life among soldiers, a step count measurement with a pedometer was carried out on 196 soldiers of the German Armed Forces over 7 days and supplemented by a questionnaire on lifestyle factors.

RESULTS

The subjects exceeded the recommended 7000-8000 steps per day, with the rank and file moving the least and the commissioned officers the most. It was also striking that the soldiers in the study moved an average of 2600 steps less per day on weekends than on weekdays.

CONCLUSIONS

Based on these findings, targeted physical activity measures can be established for the identified target groups within the framework of corporate health management in order to ensure the physical fitness of soldiers on routine duty and on deployment.

Analysing Gait Patterns in Degenerative Lumbar Spine Disease Using Inertial Wearable Sensors: An Observational Study

OBJECTIVE

Using a chest-based inertial wearable sensor, we examined the quantitative gait patterns associated with lumbar disc herniation (LDH), lumbar spinal stenosis (LSS), and chronic mechanical low back pain (CMLBP). 'Pathological gait signatures' were reported as statistically significant group difference (%) from the 'normative' gait values of an age-matched control population.

METHODS

A sample of patients presenting to the Prince of Wales Private Hospital (Sydney, Australia) with primary diagnoses of LDH, LSS, or CMLBP were recruited. Spatial, temporal, asymmetry, and variability metrics were compared with age-matched (±2 years) control participants recruited from the community. Participants were fitted at the sternal angle with an inertial measurement unit, MetaMotionC, and walked unobserved (at a self-selected pace) for 120 m along an obstacle-free, carpeted hospital corridor.

RESULTS

LDH, CMLBP, and LSS groups had unique pathological signatures of gait impairment. The LDH group (n = 33) had marked asymmetry in terms of step length, step time, stance, and single-support asymmetry. The LDH group also involved gait variability with increased step length variation. However, distinguishing the CMLBP group (n = 33) was gait variability in terms increased single-support time variation. The gait of participants with LSS (n = 22) was both asymmetric and variable in step length.

CONCLUSIONS

Wearable sensor-based accelerometry was found to be capable of detecting the gait abnormalities present in patients with LDH, LSS, and CMLBP, when compared to age-matched controls. Objective and quantitative patterns of gait deterioration uniquely varied between these subtypes of lumbar spine disease. With further testing and validation, gait signatures may aid clinical identification of gait-altering pathologies.

Accurate Step Count with Generalized and Personalized Deep Learning on Accelerometer Data

Physical activity (PA) is globally recognized as a pillar of general health. Step count, as one measure of PA, is a well known predictor of long-term morbidity and mortality. Despite its popularity in consumer devices, a lack of methodological standards and clinical validation remains a major impediment to step count being accepted as a valid clinical endpoint. Previous works have mainly focused on device-specific step-count algorithms and often employ sensor modalities that may not be widely available. This may limit step-count suitability in clinical scenarios. In this paper, we trained neural network models on publicly available data and tested on an independent cohort using two approaches: generalization and personalization. Specifically, we trained neural networks on accelerometer signals from one device and either directly applied them or adapted them individually to accelerometer data obtained from a separate subject cohort wearing multiple distinct devices. The best models exhibited highly accurate step-count estimates for both the generalization (96-99%) and personalization (98-99%) approaches. The results demonstrate that it is possible to develop device-agnostic, accelerometer-only algorithms that provide highly accurate step counts, positioning step count as a reliable mobility endpoint and a strong candidate for clinical validation.

Associations between daily steps and cognitive function among inpatients with schizophrenia

BACKGROUND

Walking is the fundamental component of taking steps and is the main form of physical activity among individuals with schizophrenia; it also offers a range of health benefits. This study aimed to examine the associations between daily steps and cognitive function and further explored how many steps were related to better cognitive function among inpatients with schizophrenia.

METHODS

Inpatients with schizophrenia were recruited from long-stay psychiatric wards across two hospitals (n=199 at site 1 and n=195 at site 2). Daily steps were collected with an accelerometer for 7 days. Four cognitive domains (attention, processing speed, reaction time, and motor speed) were tested at site 1, and two cognitive domains (attention and processing speed) were tested at site 2. The associations of daily steps and levels of steps/day with cognitive function were tested using multivariable linear regressions separated by site. Covariates included demographic variables, weight status, metabolic parameters, and clinical state.

RESULTS

Participants took an average of 7445 (±3442) steps/day. More steps were related to better attention, processing speed, reaction time, and motor speed after multivariable adjustments. Compared with participants taking <5000 steps/day, those taking ≥5000 steps/day showed significantly better processing speed. Participants taking ≥7500 steps/day were associated with better attention, better reaction time, and better motor speed than those taking <5000 steps/day.

CONCLUSION

Daily steps are associated with better cognitive function among inpatients with schizophrenia. The optimal benefit for cognitive function among this clinical population is achieving 7500 steps/day or more.

Association of physical activity on blood glucose in individuals with type 2 diabetes

Regular physical activity (PA) has been shown to improve glycemic control in persons with type 2 diabetes. This study aimed to investigate the impact of PA on blood glucose after controlling for medication use, demographics, and week of activation using a real-world population of individuals with type 2 diabetes. A longitudinal, retrospective study was performed evaluating weekly PA of Livongo members (N = 9,509), which analyzed fasting blood glucose (FBG), step counts, and daily active minutes. Linear mixed-effect modeling technique was used to investigate within member and between member effects of input variables on average weekly FBG. Of members enrolled, 6,336 (32%) had self-reported body mass index, qualified week with diabetes medications, and FBG measures. Members' baseline average age was 49.4 (SD 10.1) years old, 43% female, and 45,496 member weeks with an average of 7.2 qualified weeks (PA observable in ≥4 days) per member. Average weekly FBG was 140.5 mg/dL (SD 39.8), and average daily step counts were 4,833 (SD 3,266). Moving from sedentary (<5,000 steps per day) to active (≥5,000 steps per day) resulted in mean weekly FBG reduction of 13 mg/dL (95% CI: -22.6 to -3.14). One additional day of ≥8,000 steps reduced mean weekly FBG by 0.47 mg/dL (95% CI: -0.77 to -0.16). Members who completed 30 min of moderate to vigorous PA above the population average reduced mean weekly FBG by 7.7 mg/dL (95% CI: -13.4 to -2.0). PA is associated with a mean weekly FBG reduction of 13 mg/dL when changing from a sedentary to active lifestyle while participating in a remote diabetes monitoring program.

Proposed objective scoring algorithm for walking performance, based on relevant gait metrics: the Simplified Mobility Score (SMoS™)-observational study

Background

Walking is a fundamental part of living, and its importance is not limited by age or medical status. Reduced walking speed (WS), or gait velocity, is a sign of advancing age, various disease states, cognitive impairment, mental illness and early mortality. Activity levels, as defined in the literature as “daily step count” (DSC), is also a relevant measure of health status. A deterioration in our walking metrics, such as reduced WS and DSC, is associated with poor health outcomes. These objective measures are of such importance, that walking speed has been dubbed “the 6th vital sign”. We report a new objective measure that scores walking using the relevant metrics of walking speed and daily step count, into an easy-to-understand score from 0 (nil mobility) to 100 (excellent mobility), termed the Simplified Mobility Score (SMoS™). We have provided equal weighting to walking speed and daily step count, using a simple algorithm to score each metric out of 50.

Methods

Gait data was collected from 182 patients presenting to a tertiary hospital spinal unit with complaints of pain and reduced mobility. Walking speed was measured from a timed walk along an unobstructed pathway. Daily step count information was obtained from patients who had enabled step count tracking on their devices. The SMoS of the sample group were compared to expected population values calculated from the literature using 2-tailed Z tests.

Results

There were significantly reduced SMoS in patients who presented to the spinal unit than those expected at each age group for both genders, except for the 50–59 age bracket where no statistically significant reduction was observed. Even lower scores were present in those that went on to have surgical management. There was a significant correlation of SMoS scores with subjective disability scores such as the Oswestry Disability Index (ODI) and Visual Analogue Scale (VAS) in this cohort.

Conclusions

The SMoS is a simple and effective scoring tool which is demonstrably altered in spinal patients across age and gender brackets and correlates well with subjective disability scores. The SMoS has the potential to be used as a screening tool in primary and specialised care settings.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13018-021-02546-8.

Comparing the Effectiveness of a Wearable Activity Tracker in Addition to Counseling and Counseling Only to Reinforce Leisure-Time Physical Activity among Breast Cancer Patients: A Randomized Controlled Trial

This randomized controlled trial aimed to compare the effectiveness of a wearable activity tracker (WAT) in addition to counseling (WAT+counseling) and counseling only for reinforcing leisure-time physical activity (LTPA) among breast cancer patients during radiotherapy (RT). A total of 152 breast cancer patients who were planning to undergo radiation therapy (RT) after surgery participated in the study. The WAT+counseling group (n = 76) underwent physical activity (PA) self-monitoring using a WAT and participated in counseling. The counseling-only group (n = 76) received telephone counseling once a week during RT and did not receive WAT. The WAT+counseling group had increased relative change in self-reported LTPA (102.8) compared with the counseling-only group (57.8) immediately after RT compared to baseline. Although the relative changes of self-reported LTPA of the WAT+counseling group were higher at three and six months after the end of RT compared to in the counseling-only group, the results were not significant. The mean average daily step count of the WAT+counseling group was 9351.7, which increased to 11,592.2 during RT and 12,240.1 after RT. In the subgroup analysis, patients who did not perform regular PA before cancer diagnosis had significantly increased step counts. This study shows the feasibility of WAT with counseling to reinforce PA among breast cancer patients.

Impact of neighbourhood walkability on the onset of multimorbidity: a cohort study

Multimorbidity has become highly prevalent around the globe and been associated with adverse health outcomes and cost of care. The built environment has become an important dimension in response to obesity and associated chronic diseases by addressing population sedentariness and low physical activity.

OBJECTIVE

The aim of the following study was to examine whether there was an increased risk for multimorbidity for those living in less walkable neighbourhoods. It was hypothesised that participants residing in less walkable neighbourhoods would have a higher risk for multimorbidity.

SETTING

City of Toronto and 14 neighbouring regions/municipalities within Ontario, Canada.

PARTICIPANTS

Study participants who had completed the Canadian Community Health Survey between the year 2000 and 2012, between 20 and 64 and 65 and 95 years of age, residing within a neighbourhood captured in the Walkability Index, and who were not multimorbid at the time of interview, were selected.

INTERVENTION

The Walkability Index was the key exposure in the study, which is divided into quintiles (1-least, 5-most walkable neighbourhoods). Participants were retrospectively allocated to one of five quintiles based on their area of residency (at the time of interview) and followed for a maximum of 16 years.

PRIMARY OUTCOME MEASURE

Becoming multimorbid with two chronic conditions.

SECONDARY OUTCOME MEASURE

Becoming multimorbid with three chronic conditions.

RESULTS

Risk for multimorbidity (two chronic conditions) was highest in least compared with most walkable neighbourhoods with an HR of 1.14 (95% CI: 1.02 to 1.28, p=0.0230). While results showed an overall gradient response between decreased walkability and increased risk for multimorbidity, they were not statistically significant across all quintiles or in the older-adult cohort (65-95 years of age).

CONCLUSION

Study results seem to suggest that low neighbourhood walkability may be a risk factor for multimorbidity over time. More studies are needed to examine whether neighbourhood walkability is a potential solution for multimorbidity prevention at the population level.

Content validity and test–retest reliability with principal component analysis of the translated Malay four-item version of Paffenbarger physical activity questionnaire

Purpose

This study aimed to develop the construct validity for the Malay version of the Paffenbarger physical activity questionnaire (PPAQ) by adapting the original questionnaire to suit the local context.

Design/methodology/approach

The PPAQ was adopted and translated into the Malay language and modified to reach good content agreement among a panel of experts. A total of 65 participants aged 22–55 years old, fluent and literate in the Malay language were selected. Principal component analysis (PCA) was used to investigate construct validity. Reliability of this adapted instrument was analyzed according to types of variables.

Findings

The panel of experts reached a consensus that the final four items chosen in the adapted Malay version of PPAQ were valid and supported by a good content validity index (CVI). In total, two domains consonant with the operational domain definition were identified by PCA. Based on scores from intensity and duration of exercise, the study further divided the group into who were physically active and those who chose the unstructured physical activity. Relative reliability after a 14-day interval demonstrated moderate strength of agreement with an acceptable range of measurement error.

Research limitations/implications

PPAQ has been used worldwide but was less familiar in the local context. The Malay-four item PPAQ will provide the locally validated version of physical activity questionnaire. In addition, the authors have improved the original PPAQ by dividing the question items into two distinct domains which will effectively identify those who are physically active and those who are involved in unplanned exercise. Nevertheless, further research is recommended in bigger and heterogeneous samples along with a number of reliability tests.

Practical implications

To the authors’ knowledge, this is the first study to assess internal structure of the four-item version of PPAQ. This analysis successfully identified two components with eigenvalue more than one in the Malay four-item PPAQ. Based on this, the authors were able to separate pool of population into two groups, which are physically active and unplanned exercise (involved in unstructured exercise). The ability of the validated questionnaire to divide the population into various intensities of physical activity is a novel one, which may be useful in many public health studies where high intensity of physical activity; hence, greater energy expenditure is associated with increased longevity, better health benefit and improved cognitive function.

Social implications

In addition, the second domain “unplanned exercise” was successfully grouped together. Implication of the unplanned exercise component is to identify pool of population with active lifestyle awareness and choose the unstructured exercise instead of vigorous and formal exercising. Even though the amount of intensity and duration of incidental exercise does not reach recommended public health recommendation, it has been proven that preferred healthier lifestyle is positively associated with better cognition in later life.

Originality/value

The adapted Malay version of PPAQ has sound psychometric properties and could assist in differentiating groups of population based on their physical activity.

Effect of Different Financial Incentive Structures on Promoting Physical Activity Among Adults: A Randomized Clinical Trial

IMPORTANCE

Few adults engage in recommended levels of physical activity. Financial incentives can promote physical activity, but little is known about how the structure of these incentives influences their effectiveness (eg, how incentives are disbursed over time).

OBJECTIVE

To determine if it is more effective to disburse fixed total financial incentives at a constant, increasing, or decreasing rate to encourage physical activity.

DESIGN, SETTING, AND PARTICIPANTS

A 2-week randomized clinical trial was conducted from June 2 to 15, 2014, using an online platform that automatically records daily steps of pedometer-wearing users and awards points redeemable for cash. The study population comprised 3515 adult users of the online platform in the lower 70th percentile of steps taken among all users before treatment. Data analyses were performed from August 20, 2014, to February 1, 2018. Analysis was performed on an intent-to-treat basis.

INTERVENTIONS

Participants were randomized to either a control group or to 1 of 3 intervention groups during the 2 weeks of the study. Participants in the control group received a constant daily rate of $0.00001 per step. The 3 intervention groups received a 20-fold incentive increase ($0.00020 per step) distributed differently during the 2 weeks of the study: at a constant, increasing, or decreasing rate. Reminder emails explaining incentive schedules were sent the day before the intervention and halfway through the 2-week intervention.

MAIN OUTCOMES AND MEASURES

Change in mean daily steps during the 2-week intervention and 3 weeks after the intervention. The study had 80% power to detect a difference of 280 steps per day during the intervention at α = .05.

RESULTS

The study included 3515 participants (879 in the control condition, 879 in the constant incentive condition, 881 in the increasing incentive condition, and 876 in the decreasing incentive condition). During the intervention, compared with participants in the control group, participants receiving constant incentives logged 306.7 more steps per day (95% CI, 91.5-521.9 steps; P = .005), those receiving decreasing incentives logged 96.9 more steps per day (95% CI, 15.3-178.5 steps; P = .02), and those receiving increasing incentives logged no significant change in steps per day (1.5 steps per day; 95% CI, -81.6 to 84.7 steps; P = .97). One week after the intervention, compared with participants in the control group, only participants receiving constant incentives logged significantly more steps per day (329.5; 95% CI, 20.6-638.4; P = .04). Two and 3 weeks after the intervention, there were no significant differences compared with participants in the control group. Overall, for each $1 spent, participants in the constant incentives group logged 475.4 more steps than those in the increasing incentives group and 429.3 more steps than those in the decreasing incentives group.

CONCLUSIONS AND RELEVANCE

This study found that financial incentives for physical activity were more effective during a payment period when they were offered at a constant rate rather than an increasing or decreasing rate. However, this effectiveness dissipated shortly after the incentives were removed.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT02154256.

Relationship between objectively measured lifestyle factors and health factors in patients with knee osteoarthritis: The STROBE Study

The purpose of this study was to investigate the association between objectively-measured lifestyle factors and health factors in patients with knee osteoarthritis (OA).In this cross-sectional study, 52 patients with knee OA were examined. Lifestyle factors were measured using a wearable smartwatch (step counts, walking distance, calorie consumption, sleep hours) and by self-report (eating speed). Body mass index (BMI), waist circumference, blood pressure, muscle strength of knee extensor and hip abductor, knee pain, symptoms, daily living function, sports recreation function, quality of life by knee injury and OA outcome score (KOOS) were measured to obtain data on health factors. Correlations and regression analysis were used to analyze the relationship between lifestyle factors and health factors.KOOS subscales (pain, symptom, daily living function) and hip abductor strength were positively correlated with daily step count, which was the only independently contributing lifestyle factor. Additionally, knee pain duration and diastolic blood pressure were negatively correlated with daily step count. BMI and waist circumference showed no correlation with physical activity data, but were negatively correlated with sleep duration and eating speed.The findings of this study contribute to expanding the knowledge on how lifestyle habits of older patients with knee OA contribute to their health status. Daily step counts were associated with knee OA-related pain, symptom, function in daily living, duration of knee pain, blood pressure, and strength of hip abductor. BMI and waist circumference were associated with sleep duration and eating speed.

Self-monitoring to increase physical activity in patients with cardiovascular disease: a systematic review and meta-analysis

BACKGROUND AND AIMS

It is important to encourage physical activity in patients with cardiovascular disease (CVD), and self-monitoring is considered to contribute to increased physical activity. However, the effects of self-monitoring on CVD patients remain to be established. In this study, we examined the influence of self-monitoring on physical activity of patients with CVD via a systematic review and meta-analysis.

METHODS

Screening of randomized controlled trials only was undertaken twice on PubMed (date of appraisal: August 29, 2017). The inclusion criteria included outpatients with CVD, interventions for them, daily step counts as physical activity included in the outcome, and self-monitoring included in the intervention. Assessments of the risk of bias and meta-analysis in relation to the mean change of daily step counts were conducted to verify the effects of self-monitoring.

RESULTS

From 205 studies retrieved on PubMed, six studies were included, with the oldest study published in 2005. Participants included 693 patients of whom 541 patients completed each study program. Their mean age was 60.8 years, and the ratio of men was 79.6%. From these 6 studies, a meta-analysis was conducted with 269 patients of 4 studies including only RCTs with step counts in the intervention group and the control group, and self-monitoring significantly increased physical activity (95% confidence interval, 1916-3090 steps per day, p < 0.05). The average intervention period was about 5 months. Moreover, four studies involved intervention via the internet, and five studies confirmed the use of self-monitoring combined with other behavior change techniques.

CONCLUSION

The results suggest that self-monitoring of physical activity by patients with CVD has a significantly positive effect on their improvement. Moreover, the trend toward self-monitoring combined with setting counseling and activity goals, and increased intervention via the internet, may lead to the future development and spread of self-monitoring for CVD patients.

Evaluating utility and compliance in a patient-based eHealth study using continuous-time heart rate and activity trackers

Telemedicine has been used to remotely diagnose and treat patients, yet previously applied telemonitoring approaches have been fraught with adherence issues. The primary goal of this study was to evaluate the adherence rates using a consumer-grade continuous-time heart rate and activity tracker in a mid-risk cardiovascular patient population. As a secondary analysis, we show the ability to utilize the information provided by this device to identify information about a patient's state by correlating tracker information with patient-reported outcome survey scores. We showed that using continuous-time activity trackers with heart rate monitors can be effective in a telemonitoring application, as patients had a high level of adherence (90.0% median usage) and low attrition (0.09% decrease per day) over a 90-day period. Furthermore, data collected correlated significantly with clinically relevant patient surveys (r2=0.15 for PROMIS global health scores, p < .00001), and therefore might provide an effective signal for identifying patients in need of intervention.

Neuromuscular Control and Performance Differences Associated With Gender and Obesity in Fatiguing Tasks Performed by Older Adults

Obesity rates in the geriatric population have emerged as a serious health concern in recent decades. Yet, obesity-related differences in neuromuscular performance and motor control during fatiguing tasks, and how they are modified by gender, specifically among older adults, are still largely unexplored. The first aim of this study was to understand obesity and gender-related differences in endurance time among older adults. Motor variability has been linked with inter-individual differences in the rate of fatigue development, and as potentially revealing underlying mechanisms of neuromuscular control. Hence, the second and third aims of this study were to investigate to what extent motor variability at baseline could predict inter-individual differences in endurance time, and whether systematic obesity and gender differences exist in motor variability among older adults. Fifty-nine older adults (65 years or older) were recruited into four groups: obese male, obese female, non-obese male, and non-obese female. Participants performed submaximal intermittent isometric knee extensions until exhaustion. Knee extension force and muscle activation signals (surface electromyography) of a primary agonist muscle, the Vastus Lateralis (VL), were collected. Endurance time and metrics quantifying both the size and structure of variability were computed for the force and EMG signals, using coefficient of variation (within cycles and between cycles) and sample entropy measures. While group differences in endurance time were primarily associated with gender, adding individual motor variability measures as predictor variables explained significantly more variance in endurance time, thus highlighting the relevance of motor variability in understanding neuromotor control strategies. Males exhibited longer endurance times, higher EMG CV, lower EMG SaEn, lower force CV, and higher force SaEn than females. These findings are interpreted to indicate males as using a motor strategy involving better “distribution” of the neural efforts across synergists and antagonists to achieve better performance during the knee extension task. No obesity-related changes in endurance time were found. However, obese individuals exhibited a greater cycle-to-cycle variability in muscle activation, indicating a larger alteration in the recruitment of motor units across successive contractions and potentially increased neural costs, which may have contributed to comparable endurance time and performance as non-obese older adults.

Stroke Prevention Rehabilitation Intervention Trial of Exercise (SPRITE) - a randomised feasibility study

BACKGROUND

The value of cardiac rehabilitation (CR) after a transient ischaemic attack (TIA) or minor stroke is untested despite these conditions sharing similar pathology and risk factors to coronary heart disease. We aimed to evaluate the feasibility of conducting a trial of an adapted home-based CR programme, 'The Healthy Brain Rehabilitation Manual', for patients following a TIA/minor stroke, participants' views on the intervention and, to identify the behaviour change techniques (BCTs) used.

METHODS

Clinicians were asked to identify patients attending the Ulster Hospital, Belfast within 4 weeks of a first TIA or minor stroke. Those who agreed to participate underwent assessments of physical fitness, cardiovascular risk, quality of life and mental health, before random allocation to: Group (1) standard/usual care; (2) rehabilitation manual or (3) manual plus pedometer. All participants received telephone support at 1 and 4 weeks, reassessment at 6 weeks and an invitation to a focus group exploring views regarding the study. Two trained review authors independently assessed the manual to identify the BCTs used.

RESULTS

Twenty-eight patients were invited to participate, with 15 (10 men, 5 women; 9 TIA, 6 minor stroke; mean age 69 years) consenting and completing the study. Mean time to enrolment from the TIA/stroke was 20.5 days. Participants completed all assessment measures except VO2max testing, which all declined. The manual and telephone contact were viewed positively, as credible sources of advice. Pedometers were valued highly, particularly for goal-setting. Overall, 36 individual BCTs were used, the commonest being centred around setting goals and planning as well as social support.

CONCLUSION

Recruitment and retention rates suggest that a trial to evaluate the effectiveness of a novel home-based CR programme, implemented within 4 weeks of a first TIA/minor stroke is feasible. The commonest BCTs used within the manual revolve around goals, planning and social support, in keeping with UK national guidelines. The findings from this feasibility work have been used to further refine the next stage of the intervention's development, a pilot study.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02712385 . This study was registered prospectively on 18/03/2016.

Comparison of Different Physical Activity Measurement Methods in Adults Aged 45 to 64 Years Under Free-Living Conditions

OBJECTIVE

To compare physical activity (PA) measured by 4 methods in adults under free-living conditions in relation to selected demographic and anthropometric variables.

DESIGN

Cohort study.

SETTING

Department of Sports Medicine.

PARTICIPANTS

Clinically healthy men (81) and women (69) aged 45 to 64 years.

INTERVENTIONS

Physical activity monitoring for 7 consecutive days under free-living conditions by pedometer (P) and accelerometer (A) simultaneously and PA questionnaires: International Physical Activity Questionnaire (IPAQ) and Seven-Day Physical Activity Questionnaire Recall (SDPAR) completed after the 7-day PA.

MAIN OUTCOME MEASURES

Comparison of PA measured by pedometer, IPAQ, and SDPAR with accelerometer with regard to age, body mass, gender, and obesity type.

RESULTS

Total energy expenditure (EE) by IPAQ was higher than A (P < 0.001) in both groups regardless of age, body mass, or obesity type. Mean EE value by P was greater than A (P < 0.001) in central-obesity males and lower than A (P < 0.001) in central-obesity females. There were differences in step counts in women, unnoticed in men. SDPAR overestimated total EE in gynoid-obesity males and in central-obesity females compared with A. Ninety-five percent CI was the largest around IPAQ compared with P and SDPAR, with SDPAR showing the best agreement with A.

CONCLUSIONS

Body mass and obesity type influenced PA measurements. To monitor PA, it is recommended to use pedometer in normal bodyweight and overweight groups while accelerometer is advisable in obese subjects. A combined approach of objective and subjective PA monitoring tools is preferable.

Comparison of wrist-worn Fitbit Flex and waist-worn ActiGraph for measuring steps in free-living adults

Introduction

Accelerometers are commonly used to assess physical activity. Consumer activity trackers have become increasingly popular today, such as the Fitbit. This study aimed to compare the average number of steps per day using the wrist-worn Fitbit Flex and waist-worn ActiGraph (wGT3X-BT) in free-living conditions.

Methods

104 adult participants (n = 35 males; n = 69 females) were asked to wear a Fitbit Flex and an ActiGraph concurrently for 7 days. Daily step counts were used to classify inactive (<10,000 steps) and active (≥10,000 steps) days, which is one of the commonly used physical activity guidelines to maintain health. Proportion of agreement between physical activity categorizations from ActiGraph and Fitbit Flex was assessed. Statistical analyses included Spearman’s rho, intraclass correlation (ICC), median absolute percentage error (MAPE), Kappa statistics, and Bland-Altman plots. Analyses were performed among all participants, by each step-defined daily physical activity category and gender.

Results

The median average steps/day recorded by Fitbit Flex and ActiGraph were 10193 and 8812, respectively. Strong positive correlations and agreement were found for all participants, both genders, as well as daily physical activity categories (Spearman's rho: 0.76–0.91; ICC: 0.73–0.87). The MAPE was: 15.5% (95% confidence interval [CI]: 5.8–28.1%) for overall steps, 16.9% (6.8–30.3%) vs. 15.1% (4.5–27.3%) in males and females, and 20.4% (8.7–35.9%) vs. 9.6% (1.0–18.4%) during inactive days and active days. Bland-Altman plot indicated a median overestimation of 1300 steps/day by the Fitbit Flex in all participants. Fitbit Flex and ActiGraph respectively classified 51.5% and 37.5% of the days as active (Kappa: 0.66).

Conclusions

There were high correlations and agreement in steps between Fitbit Flex and ActiGraph. However, findings suggested discrepancies in steps between devices. This imposed a challenge that needs to be considered when using Fibit Flex in research and health promotion programs.

Bilateral changes in muscle architecture of physically active people with chronic stroke: A quantitative muscle ultrasound study

OBJECTIVE

Changes in muscle architecture after stroke are usually assessed by investigating inter-limb differences. As a result bilateral changes of muscle architecture might be missed. Our aim was to investigate whether bilateral architectural changes in skeletal muscle can be detected in chronic, physically active stroke patients using quantitative muscle ultrasound (QMUS).

METHODS

Twenty-eight patients (mean time since stroke 5.2years, median Brunnström stage 4) were recruited. QMUS images were obtained bilaterally from 2 arm and 4 leg muscles. Corrected echogenicity (muscle ultrasound grayvalue) and muscle thickness were compared to reference values obtained from healthy subjects. Correlations of muscle changes with demographic, clinical and neurophysiological characteristics were explored.

RESULTS

Out of 6 muscles, a significant increase in mean echogenicity was found in 4 paretic and 3 non-paretic side muscles. Significant decreases in mean muscle thickness were found in 2 paretic side muscles and 1 non-paretic side muscle. Echogenicity of the medial gastrocnemius correlated moderately with walking speed (inversely) and time since stroke.

CONCLUSIONS

This study showed that QMUS is a feasible technique to investigate architectural changes in skeletal muscles in the chronic phase of stroke and that abnormalities can be found in muscles on both the hemiparetic and non-paretic side.

SIGNIFICANCE

Intriguing data on bilateral changes in muscles of people with stroke is presented. Directions for future research are provided.

Effects of 10,000 steps a day on physical and mental health in overweight participants in a community setting: a preliminary study

Background

Being overweight is associated not only with physical health problems, but also with risk of mental health problems. Increased physical activity (PA) has been recommended for the prevention of cardiovascular disease; however, little is known about the effect of walking on physical and mental health outcomes.

Objective

The purpose of the study was to explore the effectiveness of a pedometer-based PA intervention on physical and mental health states.

Method

Thirty-five overweight participants with body mass index (BMI) ≥25 kg•m^–2 were selected and assigned to a 12-week pedometer-based walking program (10,000 steps•d^–1). The profile of mood states, BMI, waist circumference (WC), body fat percentage (%BF), and lean body mass (LBM) were measured before and after the 12-week intervention. The number of step counts was recorded 5 days a week in a diary booklet.

Results

The 30 participants who accumulated 10,000 steps•d^–1 had significantly lower anxiety, depression, anger, fatigue, confusion, and total mood distress scores compared with measurements taken prior to the intervention. Further, the participants had higher vigor scores compared to baseline. Regarding physical health, the participants who accrued 10,000 steps a day had significantly lower body weight, WC, BMI, and %BP. After adjustment for gender, height, and daily steps at follow-up, changes in WC were negatively associated with depression, fatigue, confusion, and total mood distress.

Conclusions

An increase in PA by accumulating at least 10,000 steps•d^–1 over a 12-week period improves physical and mood states in sedentary, overweight individuals.

Understanding walking activity in multiple sclerosis: step count, walking intensity and uninterrupted walking activity duration related to degree of disability

In multiple sclerosis (MS), physical activity (PA) is most commonly measured as number of steps, while also walking intensity and walking activity duration are keys for a healthy lifestyle. The aim of this study was to investigate (1) the number of steps persons with MS (PwMS) take; (2) the number of steps they take at low and moderate intensity; and (3) their walking activity duration for 2, 3, 6, 10, 12 and 14 uninterrupted minutes; all related to the degree of disability. 64 PwMS participated, distinguished in a mild (n = 31) and moderate MS subgroup (n = 34) based on their ambulatory dysfunction (Disease Steps). Standardized clinical tests were performed, and step data from the StepWatch Activity Monitor were collected for seven consecutive days. The results showed that (1) step count in PwMS was lower than PA recommendations, and is negatively influenced by a higher disability degree. (2) No walking was registered during 77 % of the day. PwMS are making steps for 22 % at low and only 1 % at moderate intensity. (3) Both MS subgroups rarely walk for more than six uninterrupted minutes, especially not at moderate intensity. PwMS need to be encouraged to make steps at moderate intensity, and to make steps for longer periods of time (minimal ten uninterrupted minutes).

Smartloss: A Personalized Mobile Health Intervention for Weight Management and Health Promotion

Background

Synonymous with increased use of mobile phones has been the development of mobile health (mHealth) technology for improving health, including weight management. Behavior change theory (eg, the theory of planned behavior) can be effectively encapsulated into mobile phone-based health improvement programs, which is fostered by the ability of mobile phones and related devices to collect and transmit objective data in near real time and for health care or research professionals and clients to communicate easily.

Objective

To describe SmartLoss, a semiautomated mHealth platform for weight loss.

Methods

We developed and validated a dynamic energy balance model that determines the amount of weight an individual will lose over time if they are adherent to an energy intake prescription. This model was incorporated into computer code that enables adherence to a prescribed caloric prescription determined from the change in body weight of the individual. Data from the individual are then used to guide personalized recommendations regarding weight loss and behavior change via a semiautomated mHealth platform called SmartLoss, which consists of 2 elements: (1) a clinician dashboard and (2) a mobile phone app. SmartLoss includes and interfaces with a network-connected bathroom scale and a Bluetooth-connected accelerometer, which enables automated collection of client information (eg, body weight change and physical activity patterns), as well as the systematic delivery of preplanned health materials and automated feedback that is based on client data and is designed to foster prolonged adherence with body weight, diet, and exercise goals. The clinician dashboard allows for efficient remote monitoring of all clients simultaneously, which may further increase adherence, personalization of treatment, treatment fidelity, and efficacy.

Results

Evidence of the efficacy of the SmartLoss approach has been reported previously. The present report provides a thorough description of the SmartLoss Virtual Weight Management Suite, a professionally programmed platform that facilitates treatment fidelity and the ability to customize interventions and disseminate them widely.

Conclusions

SmartLoss functions as a virtual weight management clinic that relies upon empirical weight loss research and behavioral theory to promote behavior change and weight loss.

Daily life activity in patients with left ventricular assist devices

PURPOSE

Exercise capacity is usually evaluated by peak oxygen consumption (peak-VO2). However, assessment of peak-VO2 in patients with a left ventricular assist device (LVAD) might not be the best method to provide insight into their daily life activity. The aim of this study was to assess the postoperative activity of LVAD patients using actigraphy and to compare these patients to a healthy and a heart-transplanted (HTx) population.

METHODS

Activity was continuously monitored using wrist-accelerometers in LVAD patients after implantation, during 4 weeks of rehabilitation following hospital discharge, and at 2 follow-up assessments. Peak-VO2 values measured during rehabilitation were correlated with activity. Additionally, actigraphy data from LVAD recipients were compared with data measured in healthy and HTx subjects.

RESULTS

After hospital discharge a significant increase in physical activity of LVAD recipients was observed (55 ± 28 vs. 102 ± 23 Activity Scores, n = 11, p = 0.002). During rehabilitation as well as at the follow-ups (140 ± 43 and 253 ± 33 days post-implantation) no significant increase in activity was observed. Peak-VO2 values correlated to daily activity both in LVAD and HTx patients (r &gt; 0.5). Average daily activity was significantly lower in LVAD and HTx patients than in the healthy population (130 ± 30 and 148 ± 60 vs. 245 ± 63 Activity Score; n = 18 in each group, p &lt; 0.001).

CONCLUSIONS

Activity in LVAD recipients increased substantially after hospital discharge with no further significant improvement observed during a period of 8.5 months. Similarly to the peak-VO2, also the daily activity of LVAD recipients was 53% compared to healthy subjects. These results highlight the need for an optimized physical therapy in this patient cohort.

Preventive strategies to reduce depressive symptoms in overweight and obese young adults

This study examined the relationships among problem-solving, physical activity self-efficacy, leisure-time physical activity, and depressive symptoms in overweight/obese young adults vulnerable to many health risks. Data from 96 young adults were used. The mean age and body mass index were 24.0±3.3 years old, and 36.9±7.9, respectively. There was a positive association between physical activity self-efficacy and leisure-time physical activity in African Americans, but not in non-African Americans. Better problem solving was associated with fewer depressive symptoms regardless of gender and race.

Validity of the Fitbit activity tracker for measuring steps in community-dwelling older adults

BACKGROUND

Commercially available activity monitors, such as the Fitbit, may encourage physical activity. However, the accuracy of the Fitbit in older adults remains unknown. This study aimed to determine (1) the criterion validity of Fitbit step counts compared to visual count and ActiGraph accelerometer step counts and (2) the accuracy of ActiGraph step counts compared to visual count in community-dwelling older people.

METHODS

Thirty-two community-dwelling adults aged over 60 wore Fitbit and ActiGraph devices simultaneously during a 2 min walk test (2MWT) and then during waking hours over a 7-day period. A physiotherapist counted the steps taken during the 2MWT.

RESULTS

There was excellent agreement between Fitbit and visually counted steps (intraclass correlation coefficient (ICC_2,1)=0.88, 95% CI 0.76 to 0.94) from the 2MWT, and good agreement between Fitbit and ActiGraph (ICC_2,1=0.66, 95% CI 0.41 to 0.82), and between ActiGraph and visually counted steps (ICC_2,1=0.60, 95% CI 0.33 to 0.79). There was excellent agreement between the Fitbit and ActiGraph in average steps/day over 7 days (ICC_2,1=0.94, 95% CI 0.88 to 0.97). Percentage agreement was closest for Fitbit steps compared to visual count (mean 0%, SD 4%) and least for Fitbit average steps/day compared to the ActiGraph (mean 13%, SD 25%).

CONCLUSIONS

The Fitbit accurately tracked steps during the 2MWT, but the ActiGraph appeared to underestimate steps. There was strong agreement between Fitbit and ActiGraph counted steps. The Fitbit tracker is sufficiently accurate to be used among community-dwelling older adults to monitor and give feedback on step counts.

Walk@Work: An automated intervention to increase walking in university employees not achieving 10,000 daily steps

OBJECTIVE

This study assessed the workday step counts of lower active (<10,000 daily steps) university employees using an automated, web-based walking intervention (Walk@Work).

METHODS

Academic and administrative staff (n=390; 45.6±10.8years; BMI 27.2±5.5kg/m(2); 290 women) at five campuses (Australia [x2], Canada, Northern Ireland and the United States), were given a pedometer, access to the website program (2010-11) and tasked with increasing workday walking by 1000 daily steps above baseline, every two weeks, over a six week period. Step count changes at four weeks post intervention were evaluated relative to campus and baseline walking.

RESULTS

Across the sample, step counts significantly increased from baseline to post-intervention (1477 daily steps; p=0.001). Variations in increases were evident between campuses (largest difference of 870 daily steps; p=0.04) and for baseline activity status. Those least active at baseline (<5000 daily steps; n=125) increased step counts the most (1837 daily steps; p=0.001), whereas those most active (7500-9999 daily steps; n=79) increased the least (929 daily steps; p=0.001).

CONCLUSIONS

Walk@Work increased workday walking by 25% in this sample overall. Increases occurred through an automated program, at campuses in different countries, and were most evident for those most in need of intervention.

Steps to a better Belfast: physical activity assessment and promotion in primary care

BACKGROUND

Low physical activity (PA) levels which increase the risk of chronic disease are reported by two-thirds of the general UK population. Promotion of PA by primary healthcare professionals is advocated but more evidence is needed regarding effective ways of integrating this within everyday practice. This study aims to explore the feasibility of a randomised trial of a pedometer-based intervention, using step-count goals, recruiting patients from primary care.

METHOD

Patients, aged 35-75, attending four practices in socioeconomically deprived areas, were invited to complete a General Practice PA Questionnaire during routine consultations. Health professionals invited 'inactive' individuals to a pedometer-based intervention and were randomly allocated to group 1 (prescribed a self-determined goal) or group 2 (prescribed a specific goal of 2500 steps/day above baseline). Both groups kept step-count diaries and received telephone follow-up at 1, 2, 6 and 11 weeks. Step counts were reassessed after 12 weeks.

RESULTS

Of the 2154 patients attending, 192 questionnaires were completed (8.9%). Of these, 83 were classified as 'inactive'; 41(10 men; 31 women) completed baseline assessments, with the mean age of participants being 51 years. Mean baseline step counts were similar in group 1 (5685, SD 2945) and group 2 (6513, SD 3350). The mean increase in steps/day was greater in groups 1 than 2 ((2602, SD 1957) vs (748, SD 1997) p=0.005).

CONCLUSIONS

A trial of a pedometer-based intervention using self-determined step counts appears feasible in primary care. Pedometers appear acceptable to women, particularly at a perimenopausal age, when it is important to engage in impact loading activities such as walking to maintain bone mineral density. An increase of 2500 steps/day is achievable for inactive patients, but the effectiveness of different approaches to realistic goal-setting warrants further study.

How many steps/day are enough? For adults

Physical activity guidelines from around the world are typically expressed in terms of frequency, duration, and intensity parameters. Objective monitoring using pedometers and accelerometers offers a new opportunity to measure and communicate physical activity in terms of steps/day. Various step-based versions or translations of physical activity guidelines are emerging, reflecting public interest in such guidance. However, there appears to be a wide discrepancy in the exact values that are being communicated. It makes sense that step-based recommendations should be harmonious with existing evidence-based public health guidelines that recognize that "some physical activity is better than none" while maintaining a focus on time spent in moderate-to-vigorous physical activity (MVPA). Thus, the purpose of this review was to update our existing knowledge of "How many steps/day are enough?", and to inform step-based recommendations consistent with current physical activity guidelines. Normative data indicate that healthy adults typically take between 4,000 and 18,000 steps/day, and that 10,000 steps/day is reasonable for this population, although there are notable "low active populations." Interventions demonstrate incremental increases on the order of 2,000-2,500 steps/day. The results of seven different controlled studies demonstrate that there is a strong relationship between cadence and intensity. Further, despite some inter-individual variation, 100 steps/minute represents a reasonable floor value indicative of moderate intensity walking. Multiplying this cadence by 30 minutes (i.e., typical of a daily recommendation) produces a minimum of 3,000 steps that is best used as a heuristic (i.e., guiding) value, but these steps must be taken over and above habitual activity levels to be a true expression of free-living steps/day that also includes recommendations for minimal amounts of time in MVPA. Computed steps/day translations of time in MVPA that also include estimates of habitual activity levels equate to 7,100 to 11,000 steps/day. A direct estimate of minimal amounts of MVPA accumulated in the course of objectively monitored free-living behaviour is 7,000-8,000 steps/day. A scale that spans a wide range of incremental increases in steps/day and is congruent with public health recognition that "some physical activity is better than none," yet still incorporates step-based translations of recommended amounts of time in MVPA may be useful in research and practice. The full range of users (researchers to practitioners to the general public) of objective monitoring instruments that provide step-based outputs require good reference data and evidence-based recommendations to be able to design effective health messages congruent with public health physical activity guidelines, guide behaviour change, and ultimately measure, track, and interpret steps/day.

Impoverished environment, cognition, aging and dementia

Animals living in an impoverished environment, i.e., without the possibility of physical and social activity, perform worse on cognitive tests compared to animals in an enriched environment. The same cognitive difference is also observed in humans. However, it is not clear whether this difference is caused by a decrease in cognition due to an impoverished environment or an increase due to an enriched environment. This review discusses the impact of an impoverished environment on cognition in animal experimental studies and human experimental studies with community-dwelling and institutionalized older people. Results show that the cognitive functioning of old rats is more affected by an impoverished environment than young rats. Similarly, sedentary and lonely people (impoverished environment) have worse cognitive functioning and show a faster cognitive decline than physically and socially active people. Institutionalization further aggravates cognitive decline, probably due to the impoverished environment of nursing homes. In institutions, residents spend an unnecessary and excessive amount of time in bed; out of bed they show mainly sedentary or completely passive behavior. In conclusion, older people, especially those that have been institutionalized, have poor levels of physical and social activity, which in turn has a negative impact on cognitive functioning.