The utility of the Digi-walker step counter to assess daily physical activity patterns

Association Between Step Count Measured With a Smartphone App (Pain-Note) and Pain Level in Patients With Chronic Pain: Observational Study

Background

Chronic pain is the leading cause of disability, affecting between 20% and 50% of the global population. The key recommended treatment is physical activity, which can be measured in daily life using a pedometer. However, poor adherence to pedometer use can result in incorrect measurements. Furthermore, only a few studies have investigated a possible curvilinear association between physical activity and chronic pain.

Objective

In this study, we developed the Pain-Note smartphone app to collect real-world data on step count, using the smartphone’s built-in pedometer. The aims of our research are (1) to evaluate the association between daily step count and pain level among patients with chronic pain and (2) determine if the association between daily step count and pain level was curvilinear.

Methods

We conducted a cross-sectional study based on step count data collected with the app and on the results of questionnaires, which measured the duration and intensity of pain, the widespread pain index, the symptom severity score, and the insomnia severity scale, including 7 questions for symptoms of depression. We analyzed the association between step count and pain level as a nonlinear relationship using a restricted cubic spline model. A prespecified subgroup analysis was also conducted based on fibromyalgia criteria.

Results

Between June 1, 2018, and June 11, 2020, a total of 6138 records were identified, of which 1273 were analyzed. The mean age of the participants was 38.7 years, 81.9% (1043/1273) were female, and chronic pain was present for more than 5 years in 43.2% (550/1273) of participants. Participants in the third and fourth quartiles for step count (more than 3045 and 5668 steps a day, respectively) showed a significant positive association between higher step count and lower numerical pain rating scale (mean difference –0.43, 95% CI –0.78 to –0.08, P=.02; –0.45; 95% CI –0.8 to –0.1, P=.01, respectively) than those in the first quartile (less than or equal to 1199 steps a day). The restricted cubic spline model for the association between step count and pain scale displayed a steep decline followed by a moderate decrease as the step count increased; the inflection point was 5000 steps. However, this association was not observed among participants who met the fibromyalgia criteria (491/1273), who showed a steep positive increase below 2000 steps. Data were collected between June 1, 2018, and June 11, 2020, and were analyzed on November 18, 2021.

Conclusions

Step count measured with the Pain-Note app showed a nonlinear association with pain level. Although participants with and without fibromyalgia showed a negative correlation between step count and pain level, participants who meet the criteria for fibromyalgia may present a different relationship between walking and pain perception compared to those in the general chronic pain population.

Is the number of daily walking steps in sedentary workers affected by age, gender, body mass index, education, and overall energy expenditure?

BACKGROUND

Healthy adults should take 10,000 steps per day to gain the resulting health benefits. Knowledge regarding the individual characteristics associated with daily walking steps would enhance resource allocation to those most likely to benefit from the 10,000-steps-per-day campaign.

OBJECTIVE

To determine the extent to which age, gender, body mass index (BMI), education, and energy expenditure influence daily walking steps in white-collar workers and to assess the correlation of daily walking steps among pedometer, wristband activity tracker, and smartphone application.

METHODS

A cross-sectional study was conducted on 49 sedentary workers. Daily walking steps were simultaneously assessed by three activity trackers in free-living conditions for 7 consecutive days. Associations between daily walking steps and individual factors were examined using linear regression. Correlation tests were conducted to assess the association among the three devices.

RESULTS

Multiple regression analyses showed that BMI was associated with daily walking steps. A moderate to good correlation in daily walking steps was found between the wristband activity tracker and pedometer, as well as between the smartphone application and pedometer.

CONCLUSIONS

BMI influenced daily walking steps in white-collar workers. Daily walking steps assessed by the wristband activity tracker and smartphone application differed from those assessed by the pedometer.

Self-monitored versus supervised walking programs for older adults

Walking is an effective, well accepted, inexpensive, and functional intervention. This study compared the outcomes and changes in walking behavior of self-monitored (SM) and supervised (SU) walking interventions for older adults.Participants were assigned to SM (n = 21) and SU (n = 21) walking groups according to their place of residence. Both groups exercised and wore a pedometer for 3 months.The outcome measures were step count, body mass index (BMI), and physical function. Two-way repeated-measure ANOVA and independent t tests were used to compare the intervention effects. We also plotted the trends and analyzed the walking steps weekly.Only BMI exhibited a group × time interaction. The pre-posttest differences showed knee extension muscle strength (KEMS) and Timed Up and Go test were significantly improved in the SM group, whereas BMI, KEMS, 30-s sit-to-stand, functional reach were significantly improved, but 5-m gait speed significantly slower in the SU group. For participants attending ≥50% of the sessions, those in the SM and SU groups had similar results for all variables, except for 2-min step (2MS) and daily walking step counts.Both self-monitored and supervised walking benefit older adults in most physical functions, especially lower-extremity performance, such as muscle strength, balance, and mobility. The effects of both programs do not differ significantly, except for BMI and 2MS (ie cardiopulmonary endurance). We recommend pedometer-assisted self-monitored walking for older adults because of its ability to cultivate exercise habits over the long term, whereas supervised walking to establish effective exercise intensity.

Designing and fabricating a novel medical insole with universal fluid layer with auto-customizability

Medical insoles play a significant role in pressure reduction, proper stress-strain distribution, and correcting some deformities in the foot. The aim of the present research is to design and fabricate new medical insoles with universal fluid layer. After fabricating two types of insoles including flat silicone insole with shore 17 and flat silicone insole with universal fluid layer (medical silicone with shore 17 and silicone gel with shore 0), PEDAR test using one person in two standing and walking positions in three conditions comprised without the use of medical insole, using of flat medical silicone insole, and flat silicone insole with universal fluid layer was performed. These insoles were also modeled and solved in Abacus software according to the results obtained from mechanical properties testing of silicone and PEDAR test. The results of the finite element analysis showed that absorption of stress and strain in the static state by the silicone insoles with universal fluid layer was 63% and 63%, and in the dynamic state was 84% and 89% more than those obtained by the flat silicone insoles, respectively. The experimental results of the PEDAR system also showed that in the standing state, the silicone insoles with universal fluid layer and the flat silicone insoles had 58% and 30% pressure reduction, respectively, in comparison with without insole condition. Also, in the gait state, the silicone insoles with fluid layer and the flat silicone insole showed 37% and 9% pressure reduction, respectively, in comparison with without insole condition. Eventually, it was found out that the silicone insoles with fluid layer reduce plantar pressure well in comparison to the flat silicone insoles.

Instrumental variable approach to estimating the scalar-on-function regression model with measurement error with application to energy expenditure assessment in childhood obesity

Wearable device technology allows continuous monitoring of biological markers and thereby enables study of time-dependent relationships. For example, in this paper, we are interested in the impact of daily energy expenditure over a period of time on subsequent progression toward obesity among children. Data from these devices appear as either sparsely or densely observed functional data and methods of functional regression are often used for their statistical analyses. We study the scalar-on-function regression model with imprecisely measured values of the predictor function. In this setting, we have a scalar-valued response and a function-valued covariate that are both collected at a single time period. We propose a generalized method of moments-based approach for estimation, while an instrumental variable belonging in the same time space as the imprecisely measured covariate is used for model identification. Additionally, no distributional assumptions regarding the measurement errors are assumed, while complex covariance structures are allowed for the measurement errors in the implementation of our proposed methods. We demonstrate that our proposed estimator is L₂ consistent and enjoys the optimal rate of convergence for univariate nonparametric functions. In a simulation study, we illustrate that ignoring measurement error leads to biased estimations of the functional coefficient. The simulation studies also confirm our ability to consistently estimate the function-valued coefficient when compared to approaches that ignore potential measurement errors. Our proposed methods are applied to our motivating example to assess the impact of baseline levels of energy expenditure on body mass index among elementary school-aged children.

Let's walk! Age reattribution and physical activity among older Hispanic/Latino adults: results from the ¡Caminemos! Randomized trial

Background

Many older Hispanics/Latinos are physically inactive and suffer the harmful health consequences associated with prolonged periods of inactivity. Negative age attributions that equate getting older with “slowing down” reinforce this inactive behavior. We implemented a community-based exercise intervention among insufficiently active older Hispanics/Latinos with a randomized trial of an attribution-retraining program, ¡Caminemos! (Let’s Walk!), and measured the effect of the program on walking behavior.

Methods

Five hundred and seventy-two older Hispanics/Latinos (≥60 years) were enrolled in an exercise program that randomly assigned participants to the exercise class and one of two conditions: (a) treatment (attribution retraining to dispel the notion that physical activity inevitably ceases with age) or (b) control (generic health education). Data were collected at baseline and follow-up (1, 12, and 24 months). Physical activity was determined through pedometer data and the Yale Physical Activity Survey. We also measured the intervention effects on age-expectations, self-efficacy expectations, and outcome expectations for physical activity. Mixed-effects regression models were used to determine intervention effects on prospective measures of physical activity and intrapersonal expectations.

Results

The sample had a mean age of 73 years (SD = 6.8) and was 77% female, and 76% of the sample reported income <$20,000. At baseline, control and treatment groups walked about 3000 steps/day. By 24 months, participants in both arms of the intervention maintained greater than 10,000 mean steps/day, but the difference between the groups was not statistically significant. In analyses adjusted for age, sex, education, income, health status, and acculturation, participants in both trial arms increased their mean numbers of steps at 12 and 24 months, with the treatment group showing a greater number of mean steps compared to the controls at 12 months.

Conclusions

In this group of physically inactive older Hispanics/Latinos, attribution retraining in combination with an exercise class was superior to the exercise class alone with regard to increasing walking behavior. This success was sustained at 12 months (the pre-defined primary study outcome) but not at 24 months. For older Hispanics/Latinos, enrollment in an attribution-retraining exercise program can improve an inactive lifestyle.

Trial registration

clinicaltrials.gov identifier: NCT00183014.

A systematic literature review of reviews on techniques for physical activity measurement in adults: a DEDIPAC study

The links between increased participation in Physical Activity (PA) and improvements in health are well established. As this body of evidence has grown, so too has the search for measures of PA with high levels of methodological effectiveness (i.e. validity, reliability and responsiveness to change). The aim of this “review of reviews” was to provide a comprehensive overview of the methodological effectiveness of currently employed measures of PA, to aid researchers in their selection of an appropriate tool. A total of 63 review articles were included in this review, and the original articles cited by these reviews were included in order to extract detailed information on methodological effectiveness.

Self-report measures of PA have been most frequently examined for methodological effectiveness, with highly variable findings identified across a broad range of behaviours. The evidence-base for the methodological effectiveness of objective monitors, particularly accelerometers/activity monitors, is increasing, with lower levels of variability observed for validity and reliability when compared to subjective measures. Unfortunately, responsiveness to change across all measures and behaviours remains under-researched, with limited information available.

Other criteria beyond methodological effectiveness often influence tool selection, including cost and feasibility. However, researchers must be aware of the methodological effectiveness of any measure selected for use when examining PA. Although no “perfect” tool for the examination of PA in adults exists, it is suggested that researchers aim to incorporate appropriate objective measures, specific to the behaviours of interests, when examining PA in free-living environments.

Efficacy of moderate-intensity walking provided feedback by ECE PEDO on abdominal fat in overweight and obese women: A randomized, exercise study

Objectives

The aim of this study was to investigate the effectiveness of walking with Equipment for Clever Exercise (ECE PEDO) compared to supervised, moderate-intensity, aerobic, treadmill walking exercise in overweight and obese women.

Patients and methods

Between September 2014 and January 2015, 28 women with overweight and obesity were assigned to two groups: supervised treadmill walking (Group 1, n=14) or walking with ECE PEDO (Group 2, n=14). The target heart rate (HR) corresponding to values of 50 to 70% VO2max were determined by submaximal treadmill test. Group 1 was instructed walking at their target HR on treadmill. The number of steps in a min corresponding to the target HR was calculated by a criterion pedometer and Group 2 was instructed walking in this step range recorded to the ECE PEDO giving audible feedback. Before and after a 12-week exercise program, all participants were evaluated by Body Mass Index (BMI) and waist circumference (WC). Ultrasonographic visceral fat thickness (VFT) and ergospirometric VO2max.

Results

The VFT decreased in both walking groups in association with reduced WC and weight loss and also significant increases in the VO2max after exercise intervention (p<0.05). The VFT decreased only in women by walking with ECE PEDO compared to the other group (p<0.05).

Conclusion

Our study results showed that both moderate-intensity exercise provided by a novel pedometer and supervised treadmill walking showed significant improvements in abdominal obesity and VO2max.

The Influence of Exercise on Cognitive Function in Older Hispanic/Latino Adults: Results From the "¡Caminemos!" Study

Purpose of the Study

We examined the prospective effect of an evidence-based exercise intervention (¡Caminemos!) on cognitive function among older Hispanic/Latino adults and the potential synergistic effects (if any) of an attribution-retraining intervention given to a random sample to counter negative ascriptions of the aging process.

Design and Methods

We analyzed baseline and follow-up (1- and 2-year) data collected from Hispanics/Latinos ≥60 years (N = 571) who participated in ¡Caminemos! across 27 senior centers. All participants were randomly assigned to either (a) the treatment group-a 1-hr attribution-retraining session plus a 1-hr exercise class or (b) the control group-health education plus a 1-hr exercise class. Mixed-effects linear regression was used to determine the effects of the exercise class and the attribution-retraining component on longitudinal changes in cognitive functioning, as measured by the Modified Mini-Mental State (3MS) examination.

Results

In analyses adjusted for age, sex, education, income, and medical comorbidities, participants in both trial arms displayed higher cognitive functioning scores at the 1-year (β = 1.76, p = .001) and 2-year (β = 1.37, p = .013) follow-ups when compared with original baseline scores. However, we found no significant difference in cognitive function between the treatment versus control conditions (β = 0.41, p = .582), nor were any differences found across groups over time.

Implications

The exercise intervention improved cognitive function in older Hispanics/Latinos, regardless of whether it was supplemented with the age-related attribution retraining. These findings suggest that limited access to exercise programs may be a greater obstacle in forestalling cognitive decline in older Hispanics/Latinos than the negative beliefs they might hold of the aging process.

Measurement Methods for Physical Activity and Energy Expenditure: a Review

Physical activity is defined as any bodily movement produced by skeletal muscles that results in energy expenditure. The benefits of physical activity for health maintenance have been well documented, especially in the prevention and management of chronic diseases. Therefore, accurate measurement of physical activity and energy expenditure is essential both for epidemiological studies and in the clinical context. Given the large number of available methods, it is important to have an understanding of each, especially when one needs to choose a technique to use. The purpose of this review was to discuss the components of total energy expenditure and present advantage and limitations of different methods of physical activity and energy expenditure assessment.

Efficacy of a randomized controlled self-regulation based physical activity intervention for chronic fatigue: Mediation effects of physical activity progress and self-regulation skills

OBJECTIVE

Examine the medium-term effects of a brief physical activity (PA) self-regulation (SR) based intervention (4-STEPS program) for chronic fatigue, and explore the mediating effects of PA related variables and SR skills.

METHODS

A two-arm randomized controlled trial (Usual Care vs 4-STEPS) was carried out. The 4-STEPS program consisted of Motivational Interviewing and SR-skills training. Fatigue severity (primary outcome) and impact, PA, health-related quality of life (HrQoL), and somatic and psychological distress were assessed at baseline, post-treatment (12weeks) and 12months follow-up.

RESULTS

Ninety-one patients (45 intervention and 46 controls) were included. At follow-up, there were significant treatment effects on fatigue severity (g=0.72) and fatigue impact, leisure-time PA, and physical and psychological HrQoL. No significant effects were found for number of daily steps and somatic and psychological distress. Fatigue severity at follow-up was partially mediated by post-treatment progress on a personal PA goal (effect ratio=18%).

CONCLUSION

Results suggest that a brief intervention, focusing on the formulation and pursuit of personal PA goals and the use of SR skills, produces sustained benefits for fatigue severity. Despite these promising results, dropout was high and the intervention was not beneficial for all secondary outcomes.

Impact of Booster Breaks and Computer Prompts on Physical Activity and Sedentary Behavior Among Desk-Based Workers: A Cluster-Randomized Controlled Trial

Introduction

The 15-minute work break provides an opportunity to promote health, yet few studies have examined this part of the workday. We studied physical activity and sedentary behavior among office workers and compared the results of the Booster Break program with those of a second intervention and a control group to determine whether the Booster Break program improved physical and behavioral health outcomes.

Methods

We conducted a 3-arm, cluster-randomized controlled trial at 4 worksites in Texas from 2010 through 2013 to compare a group-based, structured Booster Break program to an individual-based computer-prompt intervention and a usual-break control group; we analyzed physiologic, behavioral, and employee measures such as work social support, quality of life, and perceived stress. We also identified consistent and inconsistent attendees of the Booster Break sessions.

Results

We obtained data from 175 participants (mean age, 43 y; 67% racial/ethnic minority). Compared with the other groups, the consistent Booster Break attendees had greater weekly pedometer counts (P < .001), significant decreases in sedentary behavior and self-reported leisure-time physical activity (P < .001), and a significant increase in triglyceride concentrations (P = .02) (levels remained within the normal range). Usual-break participants significantly increased their body mass index, whereas Booster Break participants maintained body mass index status during the 6 months. Overall, Booster Break participants were 6.8 and 4.3 times more likely to have decreases in BMI and weekend sedentary time, respectively, than usual-break participants.

Conclusion

Findings varied among the 3 study groups; however, results indicate the potential for consistent attendees of the Booster Break intervention to achieve significant, positive changes related to physical activity, sedentary behavior, and body mass index.

Measurement of physical activity in obese persons: how and why? A review

[Purpose] Overweight and obesity are major risk factors for poor health, especially in children. Reduced physical activity, prompted by a sedentary lifestyle, is a major contributor. Hence, it is important to assess physical activity using standardized methods in public health to identify the risks associated with obesity. There have been no recent reports comparing such modalities for use by clinicians and researchers. In this article, some of these methods for use in the assessment of physical activity are reviewed, and their advantages and disadvantages are described. [Subjects and Methods] Electronic databases including PubMed, Medline, and Google Scholar were searched for literature, using key words Obesity, Physical activity, and Physical Behavior Monitoring. [Results] With advances in technology, various novel methods have been developed to assess physical behavior, but conventional methods are still relevant and easy to administer. [Conclusion] There are various measurement options available. Researchers may choose devices providing more accurate measurements, while clinicians may prefer portability and affordability for patients.

Initial Validation of the Activity Choice Index Among Overweight Women

PURPOSE

This prospective study was designed to evaluate psychometric properties of the Activity Choice Index (ACI), a measure for assessing one's choice to engage in more effortful, physically active behaviors in the course of daily routines over less-demanding, sedentary behaviors, in a sample of overweight women.

METHOD

The sample included 192 overweight women (Mage = 37.6 ± 7 years; Mbody mass index = 31.6 ± 4.1 kg/m(2)) who were assessed at baseline and 12 months after beginning a weight management intervention.

RESULTS

The unidimensional factor structure was confirmed for the 6-item version of the ACI. Group invariance and temporal invariance were also established. Moreover, ACI scores were positively correlated with self-reported physical activity (as measured by the 7-Day Physical Activity Recall), daily pedometer steps, and 3-day average accelerometer counts.

CONCLUSIONS

This preliminary investigation provides evidence that a relatively brief self-report instrument for assessing lifestyle physical activity choices has strong psychometric characteristics although convergent evidence is limited. The ACI has potential utility for researchers and practitioners aiming to quantify, or track change in, physical activity in everyday, free-living conditions. This early investigation sets the stage for future research to further delineate and strengthen the measurement of the ACI construct.

Cadence Feedback With ECE PEDO to Monitor Physical Activity Intensity: A Pilot Study

The purpose of this study was to examine the monitoring capabilities of the equipment for clever exercise pedometer (ECE PEDO) that provides audible feedback when the person exceeds the upper and lower limits of the target step numbers per minute and to compare step counts with Yamax SW-200 (YX200) as the criterion pedometer.A total of 30 adult volunteers (15 males and 15 females) were classified as normal weight (n = 10), overweight (n = 10), and obese (n = 10). After the submaximal exercise test on a treadmill, the moderate intensity for walking was determined by using YX200 pedometer and then the number of steps taken in a minute was measured. Lower and upper limits of steps per minute (cadence) were recorded in ECE PEDO providing audible feedback when the person's walking speed gets out of the limits. Volunteers walked for 30 minutes in the individual step count range by attaching the ECE PEDO and YX200 pedometer on both sides of the waist belt in the same session. Step counts of the volunteers were recorded. Wilcoxon, Spearman correlation, and Bland-Altman analyses were performed to show the relationship and agreement between the results of 2 devices.Subjects took an average of 3511 ± 426 and 3493 ± 399 steps during 30 minutes with ECE PEDO and criterion pedometer, respectively. About 3500 steps taken by ECE PEDO reflected that this pedometer has capability of identifying steps per minute to meet moderate intensity of physical activity. There was a strong correlation between step counts of both devices (P < 0.001, r = 0.96). Correlations across all three BMI categories and both sex remained consistently high ranging from 0.92 to 0.95. There was a high level of agreement between the ECE PEDO and YX200 pedometer in the Bland-Altman analysis.Although both devices showed a strong similarity in counting steps, the ECE PEDO provides monitoring of intensity such that a person can walk in a specified time with a desired speed.

An investigation and comparison of the effectiveness of different exercise programmes in improving glucose metabolism and pancreatic β cell function of type 2 diabetes patients

BACKGROUND

Moderately intensive aerobic exercise can improve glucose metabolism and pancreatic β cell function in diabetic patients. To date, there is no evidence to support the long-term effectiveness of home-based exercise interventions on these outcomes.

OBJECTIVE

This study investigated the effectiveness of two moderately intense exercise programmes on glucose metabolism and pancreatic β cell function in type 2 diabetes mellitus (T2DM) patients.

METHODS

A randomised controlled trial of 120 T2DM patients (with a mean age of 55.54 ± 9.09 years) was conducted. Patients were assigned by block randomisation to either an aerobic exercise group (AEG), an accumulated million steps group (AMSG), or a control group (CG); each consisting of 40 patients. Glucose metabolism and pancreatic β cell function of patients were measured at three time intervals for 1 year.

RESULTS

There was no difference in baseline scores, and respective compliance rates for the AEG and AMSG were 94.4% and 99.2%. After generalised estimating equation analysis, the AMSG results for glycated haemoglobin (HbA1c) were significantly lower than those of the CG. The insulinogenic index-acute insulin response (BIGTT-AIR ) of both exercise groups was significantly higher than that of the CG. The AMSG group improved their overall HbA1c and BIGTT-AIR results compared with the AEG group after 3 months exercise programme (T1 ) and 12 months of implementation (T2 ).

CONCLUSION

This study demonstrates that regardless of the type of exercise intervention, it is potentially beneficially effective for glucose metabolism and pancreatic β cell function in T2DM patients. The AMSG had better glucose metabolism and pancreatic β cell function compared with those in the AEG. Nurses can easily integrate exercise interventions into T2DM patient care plans.

Associations between neighbourhood walkability and daily steps in adults: a systematic review and meta-analysis

Background

Higher street connectivity, land use mix and residential density (collectively referred to as neighbourhood walkability) have been linked to higher levels of walking. The objective of our study was to summarize the current body of knowledge on the association between neighbourhood walkability and biosensor-assessed daily steps in adults.

Methods

We conducted a systematic search of PubMed, SCOPUS, and Embase (Ovid) for articles published prior to May 2014 on the association between walkability (based on Geographic Information Systems-derived street connectivity, land use mix, and/or residential density) and daily steps (pedometer or accelerometer-assessed) in adults. The mean differences in daily steps between adults living in high versus low walkable neighbourhoods were pooled across studies using a Bayesian hierarchical model.

Results

The search strategy yielded 8,744 unique abstracts. Thirty of these underwent full article review of which six met the inclusion criteria. Four of these studies were conducted in Europe and two were conducted in Asia. A meta-analysis of four of these six studies indicates that participants living in high compared to low walkable neighbourhoods accumulate 766 more steps per day (95 % credible interval 250, 1271). This accounts for approximately 8 % of recommended daily steps.

Conclusions

The results of European and Asian studies support the hypothesis that higher neighbourhood walkability is associated with higher levels of biosensor-assessed walking in adults. More studies on this association are needed in North America.

Comparison of four chondral repair techniques in the hip joint: a biomechanical study using a physiological human cadaveric model

OBJECTIVE

The objective of this study was to assess the biomechanical stability of three types of chondral flap repair techniques as well as a hydrogel scaffold implantation on the acetabular articular surface using a physiological human cadaveric model.

METHODS

Chondral flaps were created in the antero-superior zone of the acetabulum in a series of human cadaveric hip joints. The chondral flap was repaired by fibrin glue, cyanoacrylate, suture technique and an agarose hydrogel scaffold sealed with fibrin glue using six hips in each case. After each repair, the specimens were mounted in a validated jig and tested for 1500 gait cycles. In order to determine the stability of the repair, specimens were evaluated arthroscopically at specific intervals.

RESULTS

The fibrin glue and cyanoacrylate techniques were technically the easiest to perform arthroscopically, all flaps repaired with fibrin were detached at 50 cycles while those repaired with cyanoacrylate lasted for an average of 635 cycles. On the other hand, both the suture repair and scaffold implantation techniques were more technically challenging but were both stable till the endpoint of 1500 cycles.

CONCLUSION

Fibrin glue on its own does not provide sufficient fixation to repair chondral flaps on the acetabular surface. Cyanoacrylate repairs universally failed midway through the testing protocol employed here, raising doubts as to the effectiveness of that technique. The suture and hydrogel scaffold technique were the most reliable for chondral repair at any given cycle. The results of this biomechanical study demonstrate the relative effectiveness of chondral repair and fixation techniques.

Pedometer-determined physical activity patterns in a segmented school day among Hong Kong primary school children

Background/Objective

This study aimed to characterize pedometer-determined physical activity (PA) patterns in segmented school days among Hong Kong primary school children.

Methods

Participants were instructed to wear pedometers for 4 consecutive days. The overall step counts and counts at specific periods (e.g., after school, recess, and lunch) during the test days were recorded.

Results

Of the 74 recruited participants, 68 (41.2% boys, aged 10 and 11 years old) provided valid data. The mean total daily steps over the 4 test days ranged from 9064 to 9714 (standard deviation = 3140-3471 steps). The periods that contributed most toward total daily steps were after school (34.2%), recess (14.0%), and physical education (PE) classes (12.3%). Overall, Student t tests revealed that boys were more active than girls. More active children (daily step average above the sex-specific median value) accumulated significantly more steps during recess and after school than less active children (daily step average below the sex-specific median value) in both sexes (mean differences ranged from 507 steps to 1977 steps). A mixed model analysis of variance (ANOVA) revealed that students accumulated 914 steps more on days that included PE classes than on days without PE classes. A three-way ANOVA found no significant differences in body weight status (normal weight vs. overweight and obesity) and travel mode (active vs. passive modes).

Conclusion

The findings provide a better understanding of PA patterns and the contribution of the distinct segments within a school day to children's PA. This information may assist in developing more effective, appropriate, and timely school-based PA interventions for children in Hong Kong.

The association between daily steps and health, and the mediating role of body composition: a pedometer-based, cross-sectional study in an employed South African population

BACKGROUND

Walking is recognized as an easily accessible mode of physical activity and is therefore supported as a strategy to promote health and well-being. To complement walking, pedometers have been identified as a useful tool for monitoring ambulatory physical activity, typically measuring total steps/day. There is, however, little information concerning dose-response for health outcomes in relation to intensity or duration of sustained steps. We aimed to examine this relationship, along with factors that mediate it, among employed adults.

METHODS

A convenience sample, recruited from work-site health risk screening (N = 312, 37 ± 9 yrs), wore a pedometer for at least three consecutive days. Steps were classified as "aerobic" (≥100 steps/minute and ≥10 consecutive minutes) or "non-aerobic" (<100 steps/minute and/or <10 consecutive minutes). The data were sub-grouped according to intensity-based categories i.e. "no aerobic activity", "low aerobic activity" (1-20 minutes/day of aerobic activity) and "high aerobic activity" (≥21 minutes/day of aerobic activity), with the latter used as a proxy for current PA guidelines (150-minutes of moderate-intensity PA per week). Health outcomes included blood pressure, body mass index, percentage body fat, waist circumference, blood cholesterol and blood glucose. Analysis of covariance, adjusting for age, gender and total steps/day were used to compare groups according to volume and intensity-based steps categories. A further analysis compared the mediation effect of body fat estimates (percentage body fat, body mass index and waist circumference) on the association between steps and health outcomes, independently.

RESULTS

Average steps/day were 6,574 ± 3,541; total steps/day were inversely associated with most health outcomes in the expected direction (p < 0.05). The "no aerobic activity" group was significantly different from the "low aerobic activity" and "high aerobic activity" in percentage body fat and diastolic blood pressure only (P < 0.05). Percentage body fat emerged as the strongest mediator of the relationship between steps and outcomes, while body mass index showed the least mediation effect.

CONCLUSION

The study provides a presentation of cross-sectional pedometer data that relate to a combination of intensity and volume-based steps/day and its relationship to current guidelines. The integration of volume, intensity and duration of ambulatory physical activity in pedometer-based messages is of emerging relevance.

Comparisons of intensity-duration patterns of physical activity in the US, Jamaica and 3 African countries

BACKGROUND

This difference in how populations living in low-, middle or upper-income countries accumulate daily PA, i.e. patterns and intensity, is an important part in addressing the global PA movement. We sought to characterize objective PA in 2,500 participants spanning the epidemiologic transition. The Modeling the Epidemiologic Transition Study (METS) is a longitudinal study, in 5 countries. METS seeks to define the association between physical activity (PA), obesity and CVD risk in populations of African origin: Ghana (GH), South Africa (SA), Seychelles (SEY), Jamaica (JA) and the US (suburban Chicago).

METHODS

Baseline measurements of objective PA, SES, anthropometrics and body composition, were completed on 2,500 men and women, aged 25-45 years. Moderate and vigorous PA (MVPA, min/d) on week and weekend days was explored ecologically, by adiposity status and manual labor.

RESULTS

Among the men, obesity prevalence reflected the level of economic transition and was lowest in GH (1.7%) and SA (4.8%) and highest in the US (41%). SA (55%) and US (65%) women had the highest levels of obesity, compared to only 16% in GH. More men and women in developing countries engaged in manual labor and this was reflected by an almost doubling of measured MPVA among the men in GH (45 min/d) and SA (47 min/d) compared to only 28 min/d in the US. Women in GH (25 min/d), SA (21 min/d), JA (20 min/d) and SEY (20 min/d) accumulated significantly more MPVA than women in the US (14 min/d), yet this difference was not reflected by differences in BMI between SA, JA, SEY and US. Moderate PA constituted the bulk of the PA, with no study populations except SA men accumulating > 5 min/d of vigorous PA. Among the women, no sites accumulated >2 min/d of vigorous PA. Overweight/obese men were 22% less likely to engage in manual occupations.

CONCLUSION

While there is some association for PA with obesity, this relationship is inconsistent across the epidemiologic transition and suggests that PA policy recommendations should be tailored for each environment.

Compliance to step count and vegetable serve recommendations mediates weight gain prevention in mid-age, premenopausal women. Findings of the 40-Something RCT

The 40-Something RCT aimed to determine if a 12-month health professional-led intervention could modify diet and physical activity behaviour for obesity prevention, in 44-50 year old, non-obese (BMI = 18.5-29.9 kg/m(2)) premenopausal women. Women were monitored for an additional 12 months to determine if effects could be maintained. This paper aimed to explore dietary and physical activity behavioural mediators hypothesised to be causally associated with weight change. Fifty-four women were randomised to a Motivational Interviewing Intervention (MI) (n = 28; five health professional consultations) or a Self-Directed Intervention (n = 26; written advice). Compliance to 10 study recommendations was measured at three months by a four-day weighed food and physical activity record including pedometer-measured step counts, self-reported exercise minutes and sitting time. The 10 compliance scores were independently assessed in mediation models for 12- and 24-month weight change. The MI effect on step count was an increase of 0.99 points on the 10-point compliance scale (p ≤ 0.01). This MI effect on step count significantly mediated the 12 and 24 month effect on weight (12 months AB = -0.74, 95%CI = -1.95, -0.14; 24 months AB = -1.06, 95% CI = -2.56, -0.36), accounting for 37.23% and 53.79% of the effect, respectively. The MI effect on vegetable serves was an increase of 1.50 points on the compliance scale (p = 0.02). The MI effect on vegetable compliance significantly mediated the effect on weight at 24 months (AB = -0.54, 95% CI = -1.50, -0.04), accounting for 24.92% of the effect. The remaining eight dietary and physical activity compliance scores did not significantly mediate weight loss. Encouraging women to take 10,000 steps and eat five vegetable serves per day may be a promising strategy to achieve long-term weight control at mid-life.

Correlation between pedometer and the Global Physical Activity Questionnaire on physical activity measurement in office workers

Background

This study aimed to examine the correlation of physical activity levels assessed by pedometer and those by the Global Physical Activity Questionnaire (GPAQ) in a population of office workers.

Methods

A cross-sectional study was conducted on 320 office workers. A self-administered questionnaire was distributed to each office worker by hand. Physical activity level was objectively assessed by a pedometer for 7 consecutive days and subjectively assessed by the GPAQ. Based on the pedometer and GPAQ outcomes, participants were classified into 3 groups: inactive, moderately active, and highly active.

Results

No correlation in the physical activity level assessed by the pedometer and GPAQ was found (r_s = .08, P = 0.15). When considering the pedometer as the criterion for comparison, 65.3% of participants had underestimated their physical activity level using the GPAQ, whereas 9.3% of participants overestimated their physical activity level.

Conclusions

Physical activity level in office workers assessed by a subjective measure was greatly different from assessed by an objective tool. Consequently, research on physical activity level, especially in those with sedentary lifestyle, should consider using an objective measure to ensure that it closely reflects a person’s physical activity level.

Analyzing body movements within the Laban Effort Framework using a single accelerometer

This article presents a study on analyzing body movements by using a single accelerometer sensor. The investigated categories of body movements belong to the Laban Effort Framework: Strong—Light, Free—Bound and Sudden—Sustained. All body movements were represented by a set of activities used for data collection. The calculated accuracy of detecting the body movements was based on collecting data from a single wireless tri-axial accelerometer sensor. Ten healthy subjects collected data from three body locations (chest, wrist and thigh) simultaneously in order to analyze the locations comparatively. The data was then processed and analyzed using Machine Learning techniques. The wrist placement was found to be the best single location to record data for detecting Strong—Light body movements using the Random Forest classifier. The wrist placement was also the best location for classifying Bound—Free body movements using the SVM classifier. However, the data collected from the chest placement yielded the best results for detecting Sudden—Sustained body movements using the Random Forest classifier. The study shows that the choice of the accelerometer placement should depend on the targeted type of movement. In addition, the choice of the classifier when processing data should also depend on the chosen location and the target movement.

Activity of daily living is associated with circulating CD34+/KDR+ cells and granulocyte colony-stimulating factor levels in patients after myocardial infarction

The study aimed to investigate whether the extent of activities of daily living (ADL) of patients after myocardial infarction affect numbers of circulating CD34+/KDR+ and CD45+/CD34+ cells, which are supposed to protect structural and functional endothelial integrity. In a cross-sectional study, 34 male coronary artery disease patients with a history of myocardial infarction were assessed for times spent per week for specific physical ADL, including basic activities (instrumental ADL), leisure time activities, and sport activities, using a validated questionnaire. Individual specific activity times were multiplied with respective specific metabolic equivalent scores to obtain levels of specific activities. Numbers of circulating CD34+/KDR+ and CD45+/CD34+ cells were analyzed by flow cytometry. Furthermore, the colony-forming capacity of CD34+ cells and the level of granulocyte colony-stimulating factor (G-CSF) in serum were measured. Analysis revealed that the extent of total activities and basic activities, as well as total activity time, were positively correlated with numbers of circulating CD34+/KDR+ cells ( r = 0.60, 0.56, and 0.55, P < 0.05). Higher levels of total activity were also associated with increased colony-forming capacity of CD34+ cells ( r = 0.54, P < 0.05) and with higher systemic levels of G-CSF ( r = 0.44, P < 0.05). These findings indicate that even ADL-related activities of coronary artery disease patients after myocardial infarction exert stimulating effects on CD34+/KDR+ cell mobilization, potentially mediated by increased G-CSF levels. This, in turn, potentially contributes to the beneficial effects of exercise on the diseased cardiovascular system.

Relative importance of step count, intensity, and duration on physical activity's impact on vascular structure and function in previously sedentary older adults

BACKGROUND

Age-related endothelial dysfunction and vascular stiffening are associated with increased cardiovascular (CV) risk. Many groups have encouraged goals of ≥10 000 steps/day or ≥30 min/day of moderate intensity physical activity (MPA) to reduce age-related CV risk. The impact of MPA on the vasculature of older adults remains unclear.

METHODS AND RESULTS

We randomized 114 sedentary older adults ages ≥50 to 12 weeks of either no intervention (group 1), a pedometer-only intervention (group 2), or a pedometer with an interactive website employing strategies to increase the adoption of habitual physical activity (PA, group 3). Endothelial function by brachial flow-mediated dilation (FMD%), vascular stiffness by tonometry, step-count by pedometer, and PA intensity/distribution by accelerometer were measured. Step-count increased in groups 2 (5136±1554 to 9596±3907, P<0.001) and 3 (5474±1512 to 8167±3111, P<0.001) but not in group 1 (4931±1667 to 5410±2410). Both groups 2 and 3 increased MPA ≥30 min/day. Only group 3 increased MPA in continuous bouts of ≥10 minutes (P<0.001) and improved FMD% (P=0.001). Neither achievement of ≥10 000 steps/day nor ≥30 min/day of MPA resulted in improved FMD%. However, achieving ≥20 min/day in MPA bouts resulted in improved FMD%. No changes in vascular stiffness were observed.

CONCLUSIONS

MPA reverses age-related endothelial dysfunction, but may require MPA to be performed in bouts of ≥10 minutes duration for ≥20 min/day to be effective. Commonly encouraged PA goals do not guarantee improved endothelial function and may not be as effective in reducing CV risk.

CLINICAL TRIAL REGISTRATION URL

Clinicaltrials.gov. UNIQUE IDENTIFIER: NCT-01212978.

WalkMore: a randomized controlled trial of pedometer-based interventions differing on intensity messages

BACKGROUND

Pedometer-based programs have elicited increased walking behaviors associated with improvements in blood pressure in sedentary/low active postmenopausal women, a population at increased risk of cardiovascular disease. Such programs typically encourage increasing the volume of physical activity with little regard for its intensity. Recent advances in commercially available pedometer technology now permit tracking of both steps/day and time in moderate (or greater) intensity physical activity on a daily basis. It is not known whether the dual message to increase steps/day while also increasing time spent at higher intensity walking will elicit additional improvements in blood pressure relative to a message to only focus on increasing steps/day. The purpose of this paper is to present the rationale, study design, and protocols employed in WalkMore, a 3-arm 3-month blinded and randomized controlled trial (RCT) designed to compare the effects of two community pedometer-based walking interventions (reflecting these separate and combined messages) relative to a control group on blood pressure in sedentary/low active post-menopausal women, a population at increased risk of cardiovascular disease.

METHODS/DESIGN

120 sedentary/low active post-menopausal women (45-74 years of age) will be randomly assigned (computer-generated) to 1 of 3 groups: A) 10,000 steps/day (with no guidance on walking intensity/speed/cadence; BASIC intervention, n = 50); B) 10,000 steps/day and at least 30 minutes in moderate intensity (i.e., a cadence of at least 100 steps/min; ENHANCED intervention, n = 50); or a Control group (n = 20). An important strength of the study is the strict control and quantification of the pedometer-based physical activity interventions. The primary outcome is systolic blood pressure. Secondary outcomes include diastolic blood pressure, anthropometric measurements, fasting blood glucose and insulin, flow mediated dilation, gait speed, and accelerometer-determined physical activity and sedentary behavior.

DISCUSSION

This study can make important contributions to our understanding of the relative benefits that walking volume and/or intensity may have on blood pressure in a population at risk of cardiovascular disease.

TRIAL REGISTRATION

ClinicalTrials.gov Record NCT01519583, January 18, 2012.

Levels of physical activity and predictors of mortality in COPD

OBJECTIVE

To compare the Body mass index, airway Obstruction, Dyspnea, and E xercise capacity (BODE) index scores and its individual components between COPD patients with and without severe physical inactivity, as well as to correlate the number of steps/day with scores of physical activity questionnaires, age, and the BODE index (including its components).

METHODS

We included 30 patients, who were evaluated for body composition, pulmonary function (FEV1), perception of dyspnea (modified Medical Research Council scale), and exercise capacity (six-minute walk distance [6MWD]). The patients also completed the International Physical Activity Questionnaire (IPAQ), short version, and the modified Baecke questionnaire (mBQ). The level of physical activity was assessed by the number of steps/day (as determined by pedometer), using the cut-off of 4,580 steps/day to form two groups: no severe physical inactivity (SPI-) and severe physical inactivity (SPI+). We used the Mann-Whitney test or t-test, as well as Pearson's or Spearman's correlation tests, in the statistical analysis.

RESULTS

In comparison with the SPI- group, the SPI+ group showed more advanced age, higher mBQ scores (leisure domain), lower 6MWD (in m and % of predicted), and lower IPAQ scores (metabolic equivalent-walk/week domain and total). The IPAQ scores showed weak correlations with steps/day (r = 0.399), age (r = -0.459), and 6MWD-in m (r = 0.446) and in % of predicted (r = 0.422).

CONCLUSIONS

In our sample, the cut-off of 4,580 steps/day was not sensitive enough to identify differences between the groups when compared with the predictors of mortality. The IPAQ, short version score correlated with steps/day.

Optimal placement of accelerometers for the detection of everyday activities

This article describes an investigation to determine the optimal placement of accelerometers for the purpose of detecting a range of everyday activities. The paper investigates the effect of combining data from accelerometers placed at various bodily locations on the accuracy of activity detection. Eight healthy males participated within the study. Data were collected from six wireless tri-axial accelerometers placed at the chest, wrist, lower back, hip, thigh and foot. Activities included walking, running on a motorized treadmill, sitting, lying, standing and walking up and down stairs. The Support Vector Machine provided the most accurate detection of activities of all the machine learning algorithms investigated. Although data from all locations provided similar levels of accuracy, the hip was the best single location to record data for activity detection using a Support Vector Machine, providing small but significantly better accuracy than the other investigated locations. Increasing the number of sensing locations from one to two or more statistically increased the accuracy of classification. There was no significant difference in accuracy when using two or more sensors. It was noted, however, that the difference in activity detection using single or multiple accelerometers may be more pronounced when trying to detect finer grain activities. Future work shall therefore investigate the effects of accelerometer placement on a larger range of these activities.

Impact of a home-based walking intervention on outcomes of sleep quality, emotional distress, and fatigue in patients undergoing treatment for solid tumors

Exercise use among patients with cancer has been shown to have many benefits and few notable risks. The purpose of this study was to evaluate the impact of a home-based walking intervention during cancer treatment on sleep quality, emotional distress, and fatigue. Methods. A total of 138 patients with prostate (55.6%), breast (32.5%), and other solid tumors (11.9%) were randomized to a home-based walking intervention or usual care. Exercise dose was assessed using a five-item subscale of the Cooper Aerobics Center Longitudinal Study Physical Activity Questionnaire. Primary outcomes of sleep quality, distress, and fatigue were compared between the two study arms. Results. The exercise group (n = 68) reported more vigor (p = .03) than control group participants (n = 58). In dose response models, greater participation in aerobic exercise was associated with 11% less fatigue (p < .001), 7.5% more vigor (p = .001), and 3% less emotional distress (p = .03), after controlling for intervention group assignment, age, and baseline exercise and fatigue levels. Conclusion. Patients who exercised during cancer treatment experienced less emotional distress than those who were less active. Increasing exercise was also associated with less fatigue and more vigor. Home-based walking is a simple, sustainable strategy that may be helpful in improving a number of symptoms encountered by patients undergoing active treatment for cancer.

Do radiographic disease and pain account for why people with or at high risk of knee osteoarthritis do not meet physical activity guidelines?

OBJECTIVE

Knee osteoarthritis (OA) and pain are assumed to be barriers to meeting physical activity guidelines, but this has not been formally evaluated. The purpose of this study was to determine the proportions of people with and those without knee OA and knee pain who meet recommended physical activity levels through walking.

METHODS

We performed a cross-sectional analysis of community-dwelling adults from the Multicenter Osteoarthritis Study who had or who were at high risk of knee OA. Participants wore a StepWatch activity monitor to record steps per day for 7 days. The proportion of participants who met the recommended physical activity levels was defined as those accumulating≥150 minutes per week at ≥100 steps per minute in bouts lasting ≥10 minutes. These proportions were also determined for those with and those without knee OA, as classified by radiography and by severity of knee pain.

RESULTS

Of the 1,788 study participants (mean±SD age 67.2±7.7 years, mean±SD body mass index 30.7±6.0 kg/m2, 60% women), lower overall percentages of participants with radiographic knee OA and knee pain met recommended physical activity levels. However, these differences were not statistically significant between those with and those without knee OA; 7.3% and 10.1% of men (P=0.34) and 6.3% and 7.8% of women (P=0.51), respectively, met recommended physical activity levels. Similarly, for those with moderate/severe knee pain and those with no knee pain, 12.9% and 10.9% of men (P=0.74) and 6.7% and 11.0% of women (P=0.40), respectively, met recommended physical activity levels.

CONCLUSION

Disease and pain have little impact on achieving recommended physical activity levels among people with or at high risk of knee OA.

Walking to meet physical activity guidelines in knee osteoarthritis: is 10,000 steps enough?

OBJECTIVE

To study if step goals (eg, walking 10,000 steps a day) approximate meeting the 2008 Physical Activity Guidelines for Americans.

DESIGN

Cross-sectional observational cohort.

SETTING

Community.

PARTICIPANTS

People with or at high risk of knee OA (N=1788).

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

Objective physical activity data were collected over 7 consecutive days from people with or at high risk of knee OA participating in the Multicenter Osteoarthritis Study. Using activity monitor data, we determined the proportion that (1) walked ≥10,000 steps per day, (2) met the 2008 Physical Activity Guidelines, and (3) achieved both recommendations.

RESULTS

Of the subjects studied (mean age ± SD, 67±8y; mean body mass index ± SD, 31±6kg/m(2); 60% women), 16.7% of men and 12.6% of women walked ≥10,000 steps per day, while 6% of men and 5% of women met the 2008 Physical Activity Guidelines for Americans. Of those walking ≥10,000 steps per day, 16.7% and 26.7% of men and women, respectively, also met the 2008 Physical Activity Guidelines.

CONCLUSIONS

Among this sample of older adults with or at high risk of knee OA, walking ≥10,000 steps a day did not translate into meeting public health guidelines. These findings highlight the disparity between the number of steps believed to be needed per day and the recommended time-intensity guidelines to achieve positive health benefits.

Activity restriction increases deoxypyridinoline excretion in hospitalized high-risk pregnant women

PURPOSE

Activity restriction (AR), one of the most common interventions used in high-risk pregnancies, may exacerbate loss of bone mass. The purpose of this study was to determine changes over time in bone resorption in hospitalized AR women during late pregnancy.

METHODS

This was a short-term prospective study conducted in two tertiary-care obstetric hospitals. We measured urinary deoxypyridinoline (Dpd) excretion, a marker of bone resorption, once per week in a convenience sample of 14 hospitalized AR women in the third trimester and compared values at 28-31 and 34-36 weeks' gestation to those of 11 ambulatory control women. Both groups completed a bone-loading questionnaire, 3-day food intake record, and pedometer step counts at the same gestational age.

RESULTS

Urinary Dpd excretion increased from Days 1-7 (2.60 ± 0.32 nmol/mmol creatinine) to Days 22-28 (5.36 ± 0.83 nmol/mmol creatinine; p ≤ .05). Dpd excretion was higher in AR women (4.51 ± 0.31 nmol/mmol creatinine) than ambulatory women (2.72 ± 0.39 nmol/mmol creatinine) at 34-36 weeks' gestation (p ≤ .05). Energy intake between ambulatory and AR women was not different (p ≥ .05). All women met the daily requirements for calcium and vitamin D intake during pregnancy. Average daily pedometer steps for the AR women were significantly less compared to controls (1,329 ± 936 and 8,024 ± 1,890 steps/day, respectively; p ≤ .05).

CONCLUSIONS

AR leads to increased bone resorption in hospitalized pregnant women, which may impact future risk of developing osteopenia and osteoporosis.

The association between objectively measured physical activity and knee structural change using MRI

OBJECTIVES

This study describes the longitudinal association between objectively assessed physical activity (PA) and knee structural change measured using MRI.

METHODS

405 community-dwelling adults aged 51-81 years were measured at baseline and approximately 2.7 years later. MRI of the right knee at baseline and follow-up was performed to evaluate bone marrow lesions (BMLs), meniscal pathology, cartilage defects, and cartilage volume. PA was assessed at baseline by pedometer (steps/day).

RESULTS

Doing ≥10 000 steps/day was associated with BML increases (RR 1.97, 95% CI 1.19 to 3.27, p=0.009). Participants doing ≥10 000 steps/day had a 1.52 times (95% CI 1.05 to 2.20, p=0.027) greater risk of increasing meniscal pathology score, which increased to 2.49 (95% CI 1.05 to 3.93, p=0.002) in those with adverse meniscal pathology at baseline. Doing ≥10 000 steps/day was associated with a greater risk of increasing cartilage defect score in those with prevalent BMLs at baseline (RR 1.36, 95% CI 1.03 to 1.69, p=0.013). Steps/day was protective against volume loss in those with more baseline cartilage volume but led to increased cartilage loss in those with less baseline cartilage volume. (p=0.046 for interaction).

CONCLUSIONS

PA was deleteriously associated with knee structural change, especially in those with pre-existing knee structural abnormalities. This suggests individuals with knee abnormalities should avoid doing ≥10 000 steps/day. Alternatives to weight-bearing activity may be needed in order to maintain PA levels required for other aspects of health.

Walks4work: rationale and study design to investigate walking at lunchtime in the workplace setting

Background

Following recruitment of a private sector company, an 8 week lunchtime walking intervention was implemented to examine the effect of the intervention on modifiable cardiovascular disease risk factors, and further to see if walking environment had any further effect on the cardiovascular disease risk factors.

Methods

For phase 1 of the study participants were divided into three groups, two lunchtime walking intervention groups to walk around either an urban or natural environment twice a week during their lunch break over an 8 week period. The third group was a waiting-list control who would be invited to join the walking groups after phase 1. In phase 2 all participants were encouraged to walk during their lunch break on self-selecting routes. Health checks were completed at baseline, end of phase 1 and end of phase 2 in order to measure the impact of the intervention on cardiovascular disease risk. The primary outcome variables of heart rate and heart rate variability were measured to assess autonomic function associated with cardiovascular disease. Secondary outcome variables (Body mass index, blood pressure, fitness, autonomic response to a stressor) related to cardiovascular disease were also measured. The efficacy of the intervention in increasing physical activity was objectively monitored throughout the 8-weeks using an accelerometer device.

Discussion

The results of this study will help in developing interventions with low researcher input with high participant output that may be implemented in the workplace. If effective, this study will highlight the contribution that natural environments can make in the reduction of modifiable cardiovascular disease risk factors within the workplace.

Promoting walking among office employees - evaluation of a randomized controlled intervention with pedometers and e-mail messages

BACKGROUND

The purpose of the study was to evaluate a 6-month intervention to promote office-employees' walking with pedometers and e-mail messages.

METHODS

Participants were recruited by 10 occupational health care units (OHC) from 20 worksites with 2,230 employees. Voluntary and insufficiently physically active employees (N = 241) were randomized to a pedometer (STEP, N = 123) and a comparison group (COMP, N = 118). STEP included one group meeting, log-monitored pedometer-use and six e-mail messages from OHC. COMP participated in data collection. Reach, effectiveness, adoption, implementation, maintenance (RE-AIM) and costs were assessed with questionnaires (0, 2, 6, 12 months), process evaluation and interviews (12 months).

RESULTS

The intervention reached 29% (N = 646) of employees in terms of participation willingness. Logistic regression showed that the proportion of walkers tended to increase more in STEP than in COMP at 2 months in "walking for transportation" (Odds ratio 2.12, 95%CI 0.94 to 4.81) and at 6 months in "walking for leisure" (1.86, 95%CI 0.94 to 3.69). Linear model revealed a modest increase in the mean duration of "walking stairs" at 2 and 6 months (Geometric mean ratio 1.26, 95%CI 0.98 to 1.61; 1.27, 0.98 to 1.64). Adoption and implementation succeeded as intended. At 12 months, some traces of the intervention were sustained in 15 worksites, and a slightly higher number of walkers in STEP in comparison with COMP was observed in "walking stairs" (OR 2.24, 95%CI 0.94 to 5.31) and in "walking for leisure" (2.07, 95%CI 0.99 to 4.34). The direct costs of the intervention were 43 Euros per participant.

CONCLUSIONS

The findings indicate only modest impact on some indicators of walking. Future studies should invest in reaching the employees, minimizing attrition rate and using objective walking assessment. TRIAL REGISTERATION: ISRCTN79432107.

A population-based randomized controlled trial of the effect of combining a pedometer with an intervention toolkit on physical activity among individuals with low levels of physical activity or fitness

OBJECTIVES

To examine if receiving a pedometer along with an intervention toolkit is associated with increased physical activity, aerobic fitness and better self-rated health among individuals with low levels of physical activity or fitness.

METHODS

The intervention was nested in the Danish Health Examination Survey (DANHES) and carried out in 2008. Participants were randomly assigned to either a pedometer group (n=326) or a control group (n=329). Physical activity, aerobic fitness, and self-rated health were measured at baseline and at 3-month follow-up, and differences were tested by Wilcoxons signed rank tests and Chi-squared tests.

RESULTS

At follow-up, no significant differences in physical activity, aerobic fitness and self-rated health were found between the groups. However, the oldest participants in the pedometer group reported significantly more walking time compared to the controls (controls=368 min/week, pedometer group=680 min/week, P=0.05). Among participants who completed the intervention, a significant effect on total walking time was observed (median difference=225 min/week, P=0.04).

CONCLUSIONS

The results suggest that receiving a pedometer and along with an intervention toolkit can increase walking time in older individuals, but not in younger individuals. Thus, this type of intervention offers great potential for promoting physical activity in older individuals.

TRIAL REGISTRATION NUMBER

NCT01071811.

Work-related physical activity among cardiovascular specialists

BACKGROUND

Strong evidence supports positive correlation of physical activity with health benefits. Current recommendations by the American Heart Association are a minimum 30 minutes of moderate physical activity 5 days per week. This goal has been equilibrated with 10,000 steps per day.

HYPOTHESIS

Work-related physical activity of cardiovascular (CV) specialists does not meet the currently recommended daily physical activity.

METHODS

Eight cardiothoracic (CT) surgeons, 7 general cardiologists, 5 procedural cardiologists, and 8 cardiac anesthesiologists (N = 28) participated in the study. Demographic information on each participant was recorded including age, resting heart rate, body mass index, and medical and social history. Subjects were asked to wear a spring-levered pedometer on their hip for 2 weeks while at work and to record the total number of steps as well as number of hours worked each day.

RESULTS

The average daily steps walked during work were 6540, 6039, 5910, and 5553 for general cardiologists, CT surgeons, procedural cardiologists, and cardiac anesthesiologists, respectively. There were no statistically significant differences in the average number of steps taken per day among the groups. CT surgeons worked 12.4 hours per day compared to 9.3 hours by the cardiac anesthesiologists (P = 0.03).

CONCLUSIONS

In this small, single-center study, work-related physical activity of CV specialists did not meet the recommended guidelines. Obtaining the recommended activity level might be a challenge, given their busy work schedule. Therefore, CV specialists must engage in additional, out-of-hours exercise to achieve the recommended daily exercise.

The Bahasa Melayu version of the Global Physical Activity Questionnaire: reliability and validity study in Malaysia

This study aimed to assess the reliability and concurrent validity of the Bahasa Melayu version of the Global Physical Activity Questionnaire (GPAQ-M) by comparing it with the short form of the International Physical Activity Questionnaire (IPAQ-S) and objectively measuring physical activity using a Yamax DigiWalker (Yamax, Tokyo, Japan) pedometer. A total of 100 adults aged between 20 and 58 years from Kelantan in Malaysia voluntarily participated in this study. The Wilcoxon signed-rank analysis showed no significant differences in 2-week test-retest scores for total metabolic equivalent∙minutes∙per week and 4 domains of the GPAQ-M. There was a low but significant relationship between time spent on total physical activity measured by the GPAQ-M and average steps per day recorded using the pedometer (r s = .265, P = .013). Significant correlations were also found between GPAQ-M and the IPAQ-S for varying levels of intensity during physical activities (r s = .309-.466, P < .01).

Accelerometer-based on-body sensor localization for health and medical monitoring applications

In this paper, we present a technique to recognize the position of sensors on the human body. Automatic on-body device localization ensures correctness and accuracy of measurements in health and medical monitoring systems. In addition, it provides opportunities to improve the performance and usability of ubiquitous devices. Our technique uses accelerometers to capture motion data to estimate the location of the device on the user's body, using mixed supervised and unsupervised time series analysis methods. We have evaluated our technique with extensive experiments on 25 subjects. On average, our technique achieves 89% accuracy in estimating the location of devices on the body. In order to study the feasibility of classification of left limbs from right limbs (e.g., left arm vs. right arm), we performed analysis, based of which no meaningful classification was observed. Personalized ultraviolet monitoring and wireless transmission power control comprise two immediate applications of our on-body device localization approach. Such applications, along with their corresponding feasibility studies, are discussed.