Measuring Step Count Research Articles

The validity of using activity monitors to detect step count after lumbar fusion surgery

Purpose: Measuring step count using activity monitors is an increasingly popular method of quantifying physical activity, however it is unknown whether gait irregularities or the use of gait aids affect the accuracy of these devices. This study evaluates the validity of the ActivPAL3, Fitbit Flex, and Jawbone UP Move activity monitors for measuring step count in hospital inpatients after lumbar fusion.Methods: The ActivPAL3 was tested on the thigh, the Fitbit, and the Jawbone were tested on the wrist and thigh, each monitor was tested 20 times. Validity was examined by calculating the percentage of steps detected by each monitor compared to the criterion measure of observed step count, the Standard Error of Measurement, and the Intraclass Correlation Coefficient.Results: The ActivPAL3 detected 85% (SD 27%) of observed steps. On the wrist, the Fitbit detected 24% (SD 34%) and the Jawbone detected 17% (SD 40%) of observed steps. On the thigh, the Fitbit detected 66% (SD 42%) and the Jawbone detected 22% (SD 35%) of observed steps.Conclusion: The ActivPAL3 activity monitor is a sufficiently valid tool to detect step count immediately after lumbar fusion. Wrist worn monitors are not recommended in this population, particularly with patients using gait aids.Implications for RehabilitationWalking may be quantified using activity monitoring, as both an assessment tool and as an adjunct to treatmentThe ActivPAL3 is sufficiently valid for use after lumbar fusion surgeryThe Fitbit Flex and Jawbone UP Move had low accuracy, particularly when a gait aid was used

Effect of eicosapentaenoic acid on prevention of lean body mass depletion in patients with exacerbation of chronic obstructive pulmonary disease: A prospective randomized controlled trial

Systemic inflammation plays an important role in the pathogenesis of chronic obstructive pulmonary disease (COPD), resulting in depletion of lean body mass (LBM) and muscle mass. Both frequent exacerbation of COPD and low LBM are associated with poor prognosis. This study aimed to evaluate whether supplementation of eicosapentaenoic acid (EPA) prevents depletion of LBM and muscle mass in hospitalized patients with exacerbation of COPD. This was a prospective randomized controlled trial, conducted between November 2014 and October 2017. Fifty patients were randomly assigned to receive 1g/day of EPA-enriched oral nutrition supplementation (ONS) (EPA group) or EPA-free ONS of similar energy (control group) during hospitalization. The LBM index (LBMI) and the skeletal muscle mass index (SMI) were measured using a bioelectrical impedance analyzer at the time of admission and at the time of discharge. Patients underwent pulmonary rehabilitation and wore a pedometer to measure step counts and physical activity. Forty-five patients that completed the experiment were analyzed. Baseline characteristics were similar between the EPA (n=24) and control groups (n=21). There were no significant differences in energy intake, step counts, physical activity, or length of hospitalization between the two groups. Although the plasma levels of EPA significantly increased only in the EPA group, we found an insignificant increase in LBMI and SMI in the EPA group compared with the control group (LBMI:+0.35 vs.+0.19kg/m2, P=0.60, and SMI:+0.2 vs.-0.3kg/m2, P=0.17, respectively). The change in the SMI was significantly correlated with the length of hospitalization in the EPA group, but not in the control group (r=0.53, P=0.008, and r=-0.09, P=0.70, respectively). EPA-enriched ONS in patients with exacerbation of COPD during short-time hospitalization had no significant advantage in preservation of LBM and muscle mass compared with EPA-free ONS. EPA supplementation for a longer duration might play an important role in the recovery of skeletal muscle mass after exacerbation of COPD.

A6611 Fitness Trackers May Benefit Cardiovascular Health, but are They Accurate?

Objectives: Physical inactivity is an important risk factor for cardiovascular disease (CVD). Fitness trackers may help motivate consumers towards a healthier lifestyle by providing feedback, tracking and accountability to maintain regular exercise. Before placing trust in these devices, their validity and reliability must be determined. The purpose of our study was to compare total step counts obtained by Fitbit Charge HR, Fitbit Blaze and Apple Watch with the observed step counts obtained by video recordings during a treadmill protocol (walking & jogging) to evaluate the accuracy of the devices in determining step counts. Methods: Fifty apparently healthy participants (14 M/36F; average age: 26 ± 10years; mean body mass index (BMI): 26.1 ± 4.7 kg/m2) completed a 4-stage treadmill exercise protocol, consisting of walking at slow (1.9mph), moderate (3.0mph), and brisk (4.0mph) paces, and jogging (5.2 mph); 6 min duration/stage with all devices worn on the participant's non-dominant wrist. The entire protocol was video-recorded using a Canon VIXIA HF500 camcorder placed perpendicular to the treadmill to observe the steps. Video-recordings were manually assessed for step counts by two independent observers from the recorded video clips. Results: No significant differences in steps for Fitbit Charge HR, Fitbit Blaze, Apple Watch (Mean ± SD; 2967 ± 176, 2964 ± 169, 2926 ± 161 steps respectively) when compared with observed video step counts (2968 ± 146 steps; p > 0.05). The relative percent errors were 0.34%, 0.13%, and 1.41% respectively. Conclusion: The Fitbit Charge HR, Fitbit Blaze, and Apple Watch are all accurate devices for measuring step counts at various speeds of walking and running on the treadmill among healthy adults. Such simple, cost effective monitors could play a larger role to reduce the burden of CVD.

Medical-Grade Physical Activity Monitoring for Measuring Step Count and Moderate-to-Vigorous Physical Activity: Validity and Reliability Study

BackgroundThe use of physical activity (PA) monitors is commonly associated with an increase in habitual PA level in healthy and clinical populations. The PiezoRx is a medical-grade PA monitor that uses adjustable step rate thresholds to estimate moderate-to-vigorous physical activity (MVPA) and is a valid indicator of free-living PA in adults. Laboratory validation of step count derived MVPA in adults is needed to justify the use of these monitors in clinical practice to track individuals’ progress toward meeting PA guidelines that are based on MVPA, not steps.ObjectiveThe objective of our study was to assess the validity and interinstrument reliability of the PiezoRx to derive step count and MVPA in a laboratory setting compared with criterion measures and other frequently used PA monitors in a diverse sample of adults.MethodsThe adult participants (n=43; 39.4 years, SD 15.2) wore an Omron HJ-320 pedometer, an ActiGraph GT3X accelerometer, and four PiezoRx monitors during a progressive treadmill protocol conducted for 6 minutes at speeds of 2.4, 3.2, 4.0, 5.6, 6.4, and 7.2 km/hour, respectively. The four PiezoRx monitors were set at different MVPA step rate thresholds (MPA in steps/minute/VPA in steps/minute) 100/120, 110/130, height adjusted, and height+fitness adjusted.ResultsThe PiezoRx was more correlated (intraclass correlation, ICC=.97; P<.001) to manual step counting than the ActiGraph (ICC=.72; P<.001) and Omron (ICC=.62; P<.001). The PiezoRxs absolute percent error in measuring steps was 2.2% (ActiGraph=15.9%; Omron=15.0%). Compared with indirect calorimetry, the height-adjusted PiezoRx and ActiGraph were accurate measures of the time spent in MVPA (both ICC=.76; P<.001).ConclusionsThe PiezoRx PA monitor appears to be a valid and reliable measure of step count and MVPA in this diverse sample of adults. The device’s ability to measure MVPA may be improved when anthropometric differences are considered, performing at par or better than a research grade accelerometer.

Step Count and Pulse Rate Detection Based on the Contactless Image Measurement Method

Contactless exercise monitoring is a new trend that makes people feel more comfortable and unconstrained. However, the decrease in accuracy of the pulse rate measurement caused by large motion artifacts is an urgent problem to be solved. In this paper, we proposed a novel approach to monitor step count and improve the accuracy of remote pulse rate measurement based on the image detection method. We designed a chrominance-based adaptive filter and normalization (CADN) method and a domain selection scheme (DSS) to enhance the accuracy of contactless pulse rate measurement during exercise. Various exercises such as biking, stepping, and treadmill running were conducted to evaluate motion robustness of the proposed CADN + DSS and the accuracy of step counts. The results reveal that the detection rates of the proposed step count method are 99.52% and 99.77% for stepping and treadmill exercise, respectively. The pulse rate accuracy is compared with two state-of-the-art algorithms—chrominance and chrominance-based adaptive filter. The results show the proposed CADN+DSS method provides a lower discrepancy between the detected pulse rate and a ground-truth device (Polar H7) for all activities. We expand the scope of contactless measurement for physical activity detection and develop an unfettered step count and pulse rate measurement method in exercise. Therefore, step count and pulse rate can be measured synchronously without relying on any contact sensors.

VALIDITY AND RELIABILITY OF THE FITBIT FLEX™ AND ACTIGRAPH GT3X+ AT JOGGING AND RUNNING SPEEDS

Monitoring levels of physical activity, as an outcome or in guiding rehabilitation, is challenging for clinicians. Personal activity monitors are increasing in popularity and provide potential to enhance rehabilitation protocols. However, research to support the validity and reliability of these devices at jogging and running speeds is limited. The purpose of this study was to evaluate the validity of the Fitbit Flex™ and ActiGraph GT3X + for measuring step count at jogging and running speeds. A secondary purpose was to examine inter-device reliability of the Fitbit Flex™. Cross-sectional study. Thirty healthy participants aged between 19 and 50 years, completed a treadmill protocol at jogging and running speeds (8 km/h to 16 km/h). Treadmill speed was progressively increased by intervals of 2 km/h. Each interval was four minutes in duration with a two minute rest period between stages. Participants were encouraged to continue through the graded exercise test until they reached the maximum running speed that they felt they could maintain for four minutes. Step count data was collected for Fitbit Flex™ devices and the ActiGraph GT3X+. Video analysis of step count was used as the criterion measure. At speeds of 8 to 14 km/h Mean Absolute Percentage Errors were ≤1% for the Fitbit Flex™ and the ActiGraph GT3X + when compared to step count via video analysis. Standard Error of Measurement between the three Fitbit Flex™ devices was ≤ 7 steps for speeds of 8 to 14 km/h and varied between 9 to 19 steps at 16 km/h. Fitbit Flex™ devices showed good to excellent between device reliability at speeds of 8 to14 km/h (ICC 0.723 to 0.999; p ≤ 0.001). Greater variability was evident with the low participant numbers at 16 km/h (ICC 0.527 to 0.896; p ≥ 0.02). Both the Fitbit Flex™ and the ActiGraph GT3X + provide a valid account of steps taken at jogging and running speeds up to 14 km/hr, attainable by non-elite runners on a treadmill. Fitbit Flex™ devices provide equivalent step count output to each other, enabling comparison between devices during treadmill jogging and running. 2b.

Occupational Physical Activity Habits of UK Office Workers: Cross-Sectional Data from the Active Buildings Study.

Habitual behaviours are learned responses that are triggered automatically by associated environmental cues. The unvarying nature of most workplace settings makes workplace physical activity a prime candidate for a habitual behaviour, yet the role of habit strength in occupational physical activity has not been investigated. Aims of the present study were to: (i) document occupational physical activity habit strength; and (ii) investigate associations between occupational activity habit strength and occupational physical activity levels. A sample of UK office-based workers (n = 116; 53% female, median age 40 years, SD 10.52) was fitted with activPAL accelerometers worn for 24 h on five consecutive days, providing an objective measure of occupational step counts, stepping time, sitting time, standing time and sit-to-stand transitions. A self-report index measured the automaticity of two occupational physical activities (“being active” (e.g., walking to printers and coffee machines) and “stair climbing”). Adjusted linear regression models investigated the association between occupational activity habit strength and objectively-measured occupational step counts, stepping time, sitting time, standing time and sit-to-stand transitions. Eighty-one per cent of the sample reported habits for “being active”, and 62% reported habits for “stair climbing”. In adjusted models, reported habit strength for “being active” were positively associated with average occupational sit-to-stand transitions per hour (B = 0.340, 95% CI: 0.053 to 0.627, p = 0.021). “Stair climbing” habit strength was unexpectedly negatively associated with average hourly stepping time (B = −0.01, 95% CI: −0.01 to −0.00, p = 0.006) and average hourly occupational step count (B = −38.34, 95% CI: −72.81 to −3.88, p = 0.030), which may reflect that people with stronger stair-climbing habits compensate by walking fewer steps overall. Results suggest that stair-climbing and office-based occupational activity can be habitual. Interventions might fruitfully promote habitual workplace activity, although, in light of potential compensation effects, such interventions should perhaps focus on promoting moderate-intensity activity.

Financial Incentives and Health Coaching to Improve Physical Activity Following Total Knee Replacement: A Randomized Controlled Trial.

Most persons who undergo total knee replacement (TKR) do not increase their physical activity following surgery. We assessed whether financial incentives and health coaching would improve physical activity in persons undergoing TKR. We designed a factorial randomized controlled trial among persons undergoing TKR for osteoarthritis. Subjects underwent normal perioperative procedures, including postoperative physical therapy, and were assigned to 1 of 4 arms: attention control, telephonic health coaching (THC), financial incentives (FI), or THC + FI. We objectively measured step counts and minutes of physical activity using a commercial accelerometer (Fitbit Zip) and compared the changes from pre-TKR to 6 months post-TKR across the 4 study arms. Of the 202 randomized subjects, 150 (74%) provided both pre-TKR and 6 months post-TKR accelerometer data. Among completers, the mean ± SE daily step count at 6 months ranged from 5,619 ± 381 in the THC arm to 7,152 ± 407 in the THC + FI arm (adjusting for baseline values). Daily step count 6 months post-TKR increased by 680 (95% confidence interval [95% CI] -94, 1,454) in the control arm, 274 (95% CI -473, 1,021) in the THC arm, 826 (95% CI 89, 1,563) in the FI arm, and 1,808 (95% CI 1,010, 2,606) in the THC + FI arm. Weekly physical activity increased by mean ± SE 14 ± 10, 14 ± 10, 16 ± 10, and 39 ± 11 minutes in the control, THC, FI, and THC + FI arms, respectively. A dual THC + FI intervention led to substantial improvements in step count and physical activity following TKR.

Counting Steps in Activities of Daily Living in People With a Chronic Disease Using Nine Commercially Available Fitness Trackers: Cross-Sectional Validity Study.

BackgroundMeasuring physical activity with commercially available activity trackers is gaining popularity. People with a chronic disease can especially benefit from knowledge about their physical activity pattern in everyday life since sufficient physical activity can contribute to wellbeing and quality of life. However, no validity data are available for this population during activities of daily living.ObjectiveThe aim of this study was to investigate the validity of 9 commercially available activity trackers for measuring step count during activities of daily living in people with a chronic disease receiving physiotherapy.MethodsThe selected activity trackers were Accupedo (Corusen LLC), Activ8 (Remedy Distribution Ltd), Digi-Walker CW-700 (Yamax), Fitbit Flex (Fitbit inc), Lumoback (Lumo Bodytech), Moves (ProtoGeo Oy), Fitbit One (Fitbit inc), UP24 (Jawbone), and Walking Style X (Omron Healthcare Europe BV). In total, 130 persons with chronic diseases performed standardized activity protocols based on activities of daily living that were recorded on video camera and analyzed for step count (gold standard). The validity of the trackers’ step count was assessed by correlation coefficients, t tests, scatterplots, and Bland-Altman plots.ResultsThe correlations between the number of steps counted by the activity trackers and the gold standard were low (range: –.02 to .33). For all activity trackers except for Fitbit One, a significant systematic difference with the gold standard was found for step count. Plots showed a wide range in scores for all activity trackers; Activ8 showed an average overestimation and the other 8 trackers showed underestimations.ConclusionsThis study showed that the validity of 9 commercially available activity trackers is low measuring steps while individuals with chronic diseases receiving physiotherapy engage in activities of daily living.

Determining the Validity and Accuracy of Multiple Activity-Tracking Devices in Controlled and Free-Walking Conditions.

Clinicians and fitness professionals are increasingly recommending the use of activity trackers. This study compares commercially available activity tracking devices for step and distance accuracy in common exercise settings. Cross sectional. Rochester, Minnesota. Thirty-two men (n = 10) and women (n = 22) participated in the study. Researchers manually counted steps and measured distance for all trials, while participants wore 6 activity tracking devices that measured steps and distance. We computed the difference between the number of steps measured by the device and the actual number of steps recorded by the observers, as well as the distance displayed by the device and the actual distance measured. The analyses showed that both the device and walking trials affected the accuracy of the results (steps or distance, P < .001). Hip-based devices were more accurate and consistent for measuring step count. No significant differences were found among devices or locations for the distance measured. Hip-based activity tracking devices varied in accuracy but performed better than their wrist-based counterparts for step accuracy. Distance measurements for both types of devices were more consistent but lacked accuracy.

Abstract P015: Objectively Measured Step Counts Was Independently Associated With Higher Cognition in Apparently Healthy Japanese Men

Introduction: A positive association between physical activity and cognition has been reported. However, very few pertinent studies have evaluated physical activity by objective measures. Hypothesis: In a community-based sample of non-demented men, objectively measured step count was positively associated with higher cognitive function. Methods: The Shiga Epidemiological Study of Subclinical Atherosclerosis (SESSA) randomly recruited community-dwelling apparently healthy men aged 40-79 years from Shiga, Japan, and measured their step counts over 7 consecutive days using a pedometer (DIGI-Walker, DW-200) at baseline (2006-08). Among 853 mem who returned for follow-up (2010-12), we assessed their cognition using Cognitive Abilities Screening Instrument (CASI) score. The score can range from 0 to 100, and higher score indicates better cognition. We restricted our analyses to those with a valid 7-day average step count at baseline and who remained free of stroke (N=678). We calculated crude and adjusted mean CASI score according to quartile of average step count using linear regression models. All adjusting covariates used in models were asssessed at baseline including age, educational attainment, smoking, and drinking. Results: The mean [standard deviation] of age and unadjusted score were 63.8 [9.1] years and 90.8 [5.8]. Mean CASI score was higher in higher quartile of average step: 90.2, 90.4, 90.6, and 91.8 from the lowest to the highest quartile of average step ( P for trend =0.004) in a model adjusted for age and education. Further adjustment for smoking, drinking and other cardiovascular risk factors resulted in similar pattern of association (Table 1). Conclusions: Apparently healthy Japanese men with greater 7-day average step count at baseline measured with pedometer was associated with a small but significantly higher CASI score than those with fewer step count. The finding is consistent with the hypothesis that physical activity is protective for cognition in non-demented individuals.

Pedometer Measured Step Counts and Bone Mineral Density among Premenopausal Women

Pedometers have become popular physical activity measurement tools and have proven to be valid and reliable. Opportunity for bone impact comes mostly from weight bearing physical activity and is captured by the use of these devises. However, there is question about the intensity of impact needed to stimulate changes in bone tissue. Research focused on walking activity, which comprises a majority of daily physical activity for most individuals, has resulted in conflicting effects on the commencement of bone tissue remodeling. The purpose of this study was to measure pedometer based daily physical activity and determine whether these data significantly correlate with aBMD (areal bone mineral density) (g/cm2) measures among premenopausal women. A secondary purpose was to look specifically at the relationship between moderate intensity level data and aBMD. Forty-two pre-menopausal women from central Minnesota participated in the summer of 2011. Body mass index, calcium, vitamin D, total, and moderate intensity steps were tallied, and hip and lumbar spine aBMD was measured. Significant bivariate correlations (p < .05) were found between calcium and femoral, lumbar spine, and L2 aBMD measures. No correlations were found between age or vitamin D intake and aBMD measures. Significant bivariate correlations were also found between body mass index and L1, L3, L4, and total hip aBMD. No significant bivariate correlations were found between aBMD measures and total step or moderate intensity counts. Partial correlations, controlling for calcium and body mass index, did not reveal any correlations between total or moderate step counts and aBMD. It is plausible to conclude that the Omron HJ-303 pedometer may not be an appropriate tool for tracking bone building activity. Researchers need to continue to look for a consumer tool that effectively tracks this type of activity for those interested in improving bone health.

Validation of Electronic Activity Monitor Devices During Treadmill Walking.

The purpose of this study was to assess the validity of the step count measurement of commercial electronic activity monitor devices. Two popular models, Fitbit Charge HR and Mi Band 2, were selected for treadmill walking in a single session. Thirty healthy volunteers walked at five predetermined speeds (0.90, 1.12, 1.33, 1.54, and 1.78 m/s) on a treadmill with both Fitbit Charge HR and Mi Band 2 worn on their dominant hand's wrist. Observers counted the steps, with the aid of taped video, which was taken as the criterion measure for steps. The validity of the electronic activity devices was assessed by (1) Paired sample t test with the criterion measures and (2) Pearson's correlation coefficients and the corresponding p-values were calculated to compare the output of devices with manual step count. In addition, Bland-Altman plots were constructed to visually inspect the data and to assess agreement with the criterion measures. There were no significant differences in step measurement between Fitbit Charge HR and Mi Band 2 with the criterion measures. Besides, there was a very strong agreement between step count measurements obtained using the Fitbit Charge HR (r = 0.99) and the Mi Band 2 (r = 0.99), at five predetermined speeds while comparing with the observed step counts. Both Fitbit Charge HR and Mi Band 2 provided accurate step count measurement in the treadmill walking test.

Comprehensive measurement of stroke gait characteristics with a single accelerometer in the laboratory and community: a feasibility, validity and reliability study

BackgroundApplication of objective measurement of stroke gait with accelerometer-based wearable technology and associated algorithms is increasing, despite reports questioning the accuracy of this technique in quantifying specific stroke-related gait impairments. The aim of this study is to determine the feasibility, validity and reliability of a low-cost open-source system incorporating algorithms and a single tri-axial accelerometer-based wearable to quantify gait characteristics in the laboratory and community post-stroke.MethodsTwenty-five participants with stroke wore the wearable (AX3, Axivity) on the lower back during a laboratory 2 minute continuous walk (preferred pace) on two occasions a week apart and continuously in the community for two consecutive 7 day periods. Video, instrumented walkway (GaitRite) and an OPAL accelerometer-based wearable were used as laboratory references.ResultsFeasibility of the proposed system was good. The system was valid for measuring step count (ICC 0.899). Inherent differences in gait quantification between algorithm and GaitRite resulted in difficulties comparing agreement between the different systems. Agreement was moderate-excellent (ICC 0.503–0.936) for mean and variability gait characteristics vs. OPAL. Agreement was moderate-poor between the system and OPAL for asymmetry characteristics. Moderate-excellent reliability (ICC 0.534–0.857) was demonstrated for 11/14 laboratory measured gait characteristics. Community test-retest reliability was good-excellent (ICC 0.867–0.983) for all except one (ICC 0.699) of the 19 gait characteristics.ConclusionThe proposed system is a low-cost, reliable tool for quantifying gait post-stroke with multiple potential applications. Further refinement to optimise gait quantification algorithms for certain gait characteristics including gait asymmetry is required.

Validity of the Fitbit One for Measuring Activity in Community-Dwelling Stroke Survivors.

Purpose: We determined the correlation between the Fitbit One and Actical accelerometer for quantifying the 3-day step count and activity levels in community-dwelling individuals with stroke. Method: Twelve participants with a mean age of 62.6 (SD 9.3) years wore both the Fitbit One and the Actical on the non-paretic ankle for 3 days. Regression analyses were performed to examine concurrent validity between the devices for step counts and sedentary, light, moderate, and vigorous activity. The relative error of the Fitbit One compared with the Actical in measuring step count was calculated. Results: Participants spent about 80% of their days being sedentary. The associations between the Fitbit One and the Actical were r>0.80 for step count and light-intensity activity across the 3 days of free-living activity. The overall relative error in measuring step count was 3.8%, with differences between those with walking speeds of less than 0.58 metres per second and 0.58 metres per second or more (27.4% [SD 34.2] vs. -8.0% [SD 10.7], p<0.001). Conclusions: The Fitbit One was associated with the Actical accelerometer in measuring step count and light-intensity activity during free-living activity after stroke, but had lower error in capturing step count for those with faster walking speeds. The Fitbit One may not be valid for capturing higher intensity activity after stroke.

The Relationship Between Parental and Child Physical Activity in a Rural Community.

This study examined the relationship between parental and child physical activity (PA) in a rural community. Forty-one children and at least 1 parent wore pedometers to measure step count over the course of 4 days. Parents also completed a PA survey assessing parental support for PA, parental enjoyment for PA, perceived importance of PA, and their own PA levels. Parental PA level and mothers' support for PA were moderately associated with their child's PA levels. Thus, future PA promotion efforts could focus on encouraging parents, primarily mothers, to be more active to help improve their child's PA levels.

Monitoring sedentary patterns in office employees: validity of an m-health tool (Walk@Work-App) for occupational health

ObjectiveThis study validated the Walk@Work-Application (W@W-App) for measuring occupational sitting and stepping. MethodsThe W@W-App was installed on the smartphones of office-based employees (n=17; 10 women; 26±3 years). A prescribed 1-hour laboratory protocol plus two continuous hours of occupational free-living activities were performed. Intra-class correlation coefficients (ICC) compared mean differences of sitting time and step count measurements between the W@W-App and criterion measures (ActivPAL3TM and SW200Yamax Digi-Walker). ResultsDuring the protocol, agreement between self-paced walking (ICC=0.85) and active working tasks step counts (ICC=0.80) was good. The smallest median difference was for sitting time (1.5seconds). During free-living conditions, sitting time (ICC=0.99) and stepping (ICC=0.92) showed excellent agreement, with a difference of 0.5minutes and 18 steps respectively. ConclusionsThe W@W-App provided valid measures for monitoring occupational sedentary patterns in real life conditions; a key issue for increasing awareness and changing occupational sedentariness.

Evaluating Recovery Following Total Ankle Arthroplasty Using a Smartphone Mobile Application

Category: Ankle, Ankle Arthritis Introduction/Purpose: The use of smartphone applications to assist with medical care is increasing. An important aspect of total ankle arthroplasty is to allow patients to remain active and mobile following their surgery while decreasing discomfort. To our knowledge, no other studies have quantitatively and qualitatively assessed post-operative mobility following total ankle arthroplasty. The goals of the present study were to assess the reliability of a mobile health application to measure step counts, to correlate mobility with pain and functional assessments, and to determine average walking ability following total ankle arthroplasty. Methods: A smartphone app, Moves, used a pedometer to record the number of steps taken daily. The device was chosen because it is a free application and is compatible with both iPhone and Android. Patients were identified through the OR schedule and called one month prior to surgery. After obtaining consent, patients completed an online consent form, an online pre- operative survey and downloaded the Moves application to their smartphone. Mobility data was gathered for the month prior to surgery and from post-operative months 3-9. Beginning at 3 months post-operatively, patients completed a weekly online survey until 6 months post-operatively, which was then completed biweekly until study completion at 9 months post-operatively. The correlation of step count with pain and quality of life scores as reported through the Foot and Ankle Outcome Score (FAOS) and pain as reported by the Numeric Rating Scale (NRS) were assessed via Spearman’s rank correlation coefficients. Results: 46 patients (23 female and 23 males) were enrolled with a mean age of 63.6 years (range 33.0 to 78.9). Maximum daily step count increased from a median (1st quartile, 3 rd quartile) 4348 (2737, 7253) steps pre-operatively to 4411 (3237, 9614) steps post-operatively, with patients continuing to increase their step count at 9 months post-operatively. Step count showed weak correlation with FAOS pain scores (rs=0.21 [95% CI: 0.08, 0.33]), FAOS QOL scores (rs=0.11 [95% CI: -0.02, 0.24]), and NRS pain scores (rs=-0.27 [95% CI: -0.38, -0.14]). Conclusion: Using mobile technology following total ankle arthroplasty may be useful for patients to quantitatively assess their recovery; however, this application fails to correlate increased ambulation with qualitative assessments such as pain and quality of life. While improved pain and quality of life scores only showed weak correlations with increased ambulation, it is important to note that pain improved despite increasing ambulation in the post-operative period. In addition, it may be that differences in functional outcomes do not appear until beyond 9 months as step count has not yet plateaued at that point.

Clinical gait evaluation of patients with knee osteoarthritis

Knee osteoarthritis (KOA) is the most common osteoarthritis in lower limbs, and gait measurement is important to evaluate walking function of KOA patients before and after treatment. The third generation Intelligent Device for Energy Expenditure and Activity (IDEEA3) is a portable gait analysis system to evaluate gaits. This study is to evaluate the accuracy and reliability of IDEEA3 for gait measurement of KOA patients. Meanwhile, gait differences between KOA patients and healthy subjects are examined. Twelve healthy volunteers were recruited for measurement comparison of gait cycle (GC), cadence, step length, velocity and step counts between a motion analysis system and a high-speed camera (GoPro Hero3). Twenty-three KOA patients were recruited for measurement comparison of former five parameters between GoPro Hero3 and IDEEA3. Paired t-test, Concordance Correlation Coefficient (CCC) and Intraclass Correlation Coefficient (ICC) were used for data analysis. All p-values of paired t-tests for GC, cadence, step length and velocity were greater than 0.05 while all CCC and ICC results were above 0.95. The measurements of GC, cadence, step length, velocity and step counts by motion analysis system are highly consistent with the measurements by GoPro Hero3. The measurements of former parameters by GoPro Hero3 are not statistically different from the measurements by IDEEA3. IDEEA3 can be effectively used for the measurement of GC, cadence, step length, velocity and step counts in KOA patients. The KOA patients walk with longer GC, lower cadence, shorter step length and slower speed compared with healthy subjects in natural speed with flat shoes.

Associations between seasonal meteorological conditions and the daily step count of adults in Yokohama, Japan: Results of year-round pedometer measurements in a large population.

People's year-round interpersonal step count variations according to meteorological conditions are not fully understood, because complete year-round data from a sufficient sample of the general population are difficult to acquire. This study examined the associations between meteorological conditions and objectively measured step counts using year-round data collected from a large cohort (N = 24,625) in Yokohama, Japan from April 2015 to March 2016.Two-piece linear regression analysis was used to examine the associations between the monthly median daily step count and three meteorological indices (mean values of temperature, temperature-humidity index (THI), and net effective temperature (NET)).The number of steps per day peaked at temperatures between 19.4 and 20.7 °C. At lower temperatures, the increase in steps per day was between 46.4 and 52.5 steps per 1 °C increase. At temperatures higher than those at which step counts peaked, the decrease in steps per day was between 98.0 and 187.9 per 1 °C increase. Furthermore, these effects were more obvious in elderly than non-elderly persons in both sexes. A similar tendency was seen when using THI and NET instead of temperature. Among the three meteorological indices, the highest R2 value with step counts was observed with THI in all four groups.Both high and low meteorological indices discourage people from walking and higher values of the indices adversely affect step count more than lower values, particularly among the elderly. Among the three indices assessed, THI best explains the seasonal fluctuations in step counts.