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Introduction: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. Materials and Methods: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. Results: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. Conclusion:Both Fitbit Charge HR and Mi Band 2 provided accurate step count measurement in the treadmill walking test. [ABSTRACT FROM AUTHOR]

Background: 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. Purpose: 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™. Study Design: Cross-sectional study Methods: 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. Results: 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 FlexTM 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). Conclusion: 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. Level of evidence: 2b [ABSTRACT FROM AUTHOR]

Wearable physical activity trackers are a popular and useful method to collect biometric information at rest and during exercise. The purpose of this systematic review was to summarize recent findings of wearable devices for biometric information related to steps, heart rate, and caloric expenditure for several devices that hold a large portion of the market share. Searches were conducted in both PubMed and SPORTdiscus. Filters included: humans, within the last 5 years, English, full-text, and adult 19+ years. Manuscripts were retained if they included an exercise component of 5-min or greater and had 20 or more participants. A total of 10 articles were retained for this review. Overall, wearable devices tend to underestimate energy expenditure compared to criterion laboratory measures, however at higher intensities of activity energy expenditure is underestimated. All wrist and forearm devices had a tendency to underestimate heart rate, and this error was generally greater at higher exercise intensities and those that included greater arm movement. Heart rate measurement was also typically better at rest and while exercising on a cycle ergometer compared to exercise on a treadmill or elliptical machine. Step count was underestimated at slower walking speeds and in free-living conditions, but improved accuracy at faster speeds. The majority of the studies reviewed in the present manuscript employed different methods to assess validity and reliability of wearable technology, making it difficult to compare devices. Standardized protocols would provide guidance for researchers to evaluate research-grade devices as well as commercial devices used by the lay public. [ABSTRACT FROM AUTHOR]

Background: Exercise programmes consisting of stepping were found to significantly reduce incidence of falls in the elderly. The aim of this case study was to evaluate the feasibility of step counts and to identify a specific dose, i.e. the amount and intensity of stepping during a multicomponent balance specific exercise programme. Material and methods: Thirty fit community-dwelling older adults (69.7 ±6.2 years) participated in the study. The number of steps and the intensity of stepping per training unit was recorded with StepWatch pedometers. Results: The average recorded number of steps per one-hour training unit was 1100 ±215. The intensity level of the activity was on average high for 43.6 ±16.6% of the unit time and moderate for 45.9 ±14.2% of the unit time, whereas only 9.9% ±3.9 of the unit time was in the low level range. Conclusions: The use of pedometers, i.e. step counts, is feasible to monitor the intensity of the training as well as the volume and progression if needed for the balance specific exercise programmes. Additionally, this case study demonstrates that balance specific exercise programme can be organised in the way to facilitate balance by means of volitional and reactive stepping. [ABSTRACT FROM AUTHOR]

The increasing prevalence of chronic heart failure requires new and more cost-efficient methods of chronic heart failure treatment. In the search for comprehensive and more costeffective disease management, the use of self-monitoring devices has become increasingly popular. However, the usability of these wireless self-trackers needs to be evaluated if they are to be successfully implemented within a healthcare system. The aim of this study is to evaluate the usability of six self-tracking devices for use in telerehabilitation of heart failure patients. The devices were evaluated by 22 healthy volunteers who used them for 48 hours. Based on structured interviews, the volunteers rated the devices for their user-friendliness, design, comfort, and motivation. Also, the devices' step count precision was assessed using a treadmill walking test. Of the six devices subject to user tests, the Fitbit One, Fitbit Charge HR, Garmin Vivofit 2, and Beddit Sleep Tracker received significantly higher average scores than the Jawbone UP3 and Jawbone UP24, based on the structured interviews, p < 0.001. The Fitbit One and the Garmin Vivofit 2 received the lowest error percentage rates during the walking tests. The results indicate that in terms of overall usability for telerehabilitation purposes, the most suitable self-tracking devices would be the Fitbit One, Garmin Vivofit 2, and the Fitbit Charge HR. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Pulmonary rehabilitation (PR) may not suit all individuals with chronic obstructive pulmonary disease (COPD) and may not result in increased physical activity. Higher levels of physical activity are associated with reduced mortality and morbidity. The aim of this study was to assess the feasibility of conducting a trial to investigate the effectiveness of a clinician-facilitated physical activity intervention (PAI) versus PR in improving physical activity in patients with COPD referred to PR. In this randomised controlled mixed methods feasibility study, all patients referred to PR who were eligible and willing were assessed at baseline and then randomised to the PAI or to PR. The assessments were repeated post-intervention and at 3-month follow-up. The main outcome was step count measured by Actigraph. Semi-structured interviews were conducted post-intervention. The N = 50 patients; mean (SD) age, 64.1(8.6) years, 24M were recruited and randomised; N = 23 (PAI) and n = 26 (PR): one patient was excluded from the analysis as that person did not meet the GOLD diagnostic criteria. Key feasibility criteria were met; recruitment was 11%, dropouts in PAI were 26% (n = 6) and 50% (n = 13/26) PR. Participants in both groups experienced a range of health benefits from their respective programmes. The PAI appears to be effective in increasing step counts in people with COPD: mean change (standard deviation) [confidence interval] for the PAI group was 972.0(3230.3)[-1080.3 to 3024.4], n = 12 and 4.3(662.7)[-440.9 to 449.5], n = 11 for the PR group. The PAI met all domains of fidelity. This study provides key information to inform a future-randomised controlled trial in physical activity. [ABSTRACT FROM AUTHOR]

Background: Individuals with hypertrophic cardiomyopathy (HCM) may be asymptomatic or display activity-limiting symptoms. A common cause of symptoms is left ventricular outflow tract obstruction (LVOTO), which may impact the individuals' ability to undertake physical activity. This study sought to examine daily step count as a potential marker of exercise capacity, which may represent a proxy marker of disease severity in HCM.Methods: A cross-sectional study of 63 HCM patients was conducted from March to November 2015. Participants wore an ActiGraph GT3X+ (Pensacola, Florida, USA) accelerometer for 7 days. Minutes per day of light, moderate and vigorous physical activity and step count were calculated, and those with LVOTO were compared to those without. Similarly, those with good functional capacity (New York Heart Association; NYHA class I) were compared to those with NYHA class II-IV.Results: The majority of HCM patients were male (n=45, 71%) with mean age of 48.8±14.9years. Hypertrophic cardiomyopathy patients with history of LVOTO and those NYHA class II-IV took significantly fewer steps per day (LV obstruction: 5527±2370 versus 7027±2095, p=0.01 and NYHA: 5346±1898 versus 6801±2339, p=0.03). No differences were observed across the different intensities of physical activity.Conclusions: Measurement of daily step count may be a useful and simple tool to determine exercise capacity and provide an indicator of disease severity in individuals with HCM. [ABSTRACT FROM AUTHOR]

Background: Walking is a natural and effective form of physical activity and the core of all daily locomotion movements. The generally accepted value of 10,000 steps/day does not correspond with the elderly people; the recommendation for old person is above the limit of 7,100 steps/day. Purpose: The aim of this study was to characterize a group of elderly women attending the University of Third Age at the Faculty of Physical Culture, Palacký University Olomouc (U3A FPC UP Olomouc) regarding their body composition and physical activity and assess the differences between selected parameters of body composition in physically active and inactive women. Methods: The research group consisted of 106 women (aged 58-77 years) attending the U3A FPC UP Olomouc. The measurement of body composition was carried out using the bioelectric impedance method through the InBody 720 device. The number of steps was monitored using the Yamax DigiWalker SW-700 pedometer. To verify the strength of relation between variables Pearson correlation coefficient were calculated. Results: The participants are categorized as physically active women who meet the recommended limit of the number of steps/day with lowered physical activity at weekends, with the average value of the sample being above the limit of 7,100 steps/day. The research group was categorized as overweight according BMI (Body Mass Index; 26.4 ± 3.4 kg/m2) and BFMI (Body Fat Mass Index; 9.4 ± 2.7 kg/m2), with a risk of abdominal obesity (VFA: 118.0 ± 27.7 cm2, WHR: 94.2 ± 5.8%). The difference between physical active and inactive women and average values of the selected parameters of body composition was not statistically significant. Conclusion: The influence of physical activity, measured by the number of steps on the body composition, is thus very minimal and the intensity and spectrum of physical activity play a significant role. [ABSTRACT FROM AUTHOR]

Background: The beneficial effects of physical activity (PA) on the health and well-being of individuals are well established. Physical therapists are often involved in promoting optimal levels of PA in various clinical populations. However, little is known regarding levels of PA or factors associated with PA in individuals with lower extremity (LE) amputations. Objectives: To perform a systematic search and synthesize the literature on PA and identify factors associated with PA in individuals with LE amputations. Major findings: We systematically reviewed the literature pertaining to PA in adults with a LE amputation. Thirty-five articles from 1995 to 2016 met the inclusion criteria and were included in this narrative review. The majority of participants with LE amputations were found to be sedentary, taking approximately 3000-4000 steps/day. Those with a vascular etiology of amputation or a transfemoral amputation were less active compared to those with a traumatic or transtibial amputation. The manipulation of prosthetic components was often not correlated with changes in PA. Some factors related to PA (i.e. endurance, K-level, use of an assistive device, history of falls) seemed to correlate with PA. Due to a paucity of research, no conclusions were drawn on the physical and mental health benefits of PA in patients with LE amputations or the number of steps/day necessary to optimize health benefits. Conclusions: This review reveals the need for continued investigations on PA and the most important factors impacting levels of PA in individuals with LE amputations. [ABSTRACT FROM AUTHOR]

Despite the accessibility of several step count measurement systems, count accuracy in real environments remains a major challenge. Microelectromechanical systems and pressure sensors seem to present a potential solution for step count accuracy. The purpose of this study was to equip an insole with pressure sensors and to test a novel and potentially more accurate method of detecting steps. Methods: Five force-sensitive resistors (FSR) were integrated under the heel, the first, third, and fifth metatarsal heads and the great toe. This system was tested with twelve healthy participants at self-selected and maximal walking speeds in indoor and outdoor settings. Step counts were computed based on previously reported calculation methods, individual and averaged FSR-signals, and a new method: cumulative sum of all FSR-signals. These data were compared to a direct visual step count for accuracy analysis. Results: This system accurately detected steps with success rates ranging from 95.5 ± 3.5% to 98.5 ± 2.1% (indoor) and from 96.5 ± 3.9% to 98.0 ± 2.3% (outdoor) for self-selected walking speeds and from 98.1 ± 2.7% to 99.0 ± 0.7% (indoor) and 97.0 ± 6.2% to 99.4 ± 0.7% (outdoor) for maximal walking speeds. Cumulative sum of pressure signals during the stance phase showed high step detection accuracy (99.5 ± 0.7%⁻99.6 ± 0.4%) and appeared to be a valid method of step counting. Conclusions: The accuracy of step counts varied according to the calculation methods, with cumulative sum-based method being highly accurate.

Accelerometer-based commercial activity trackers are a low-cost and convenient method for monitoring and assessing health measures such as gait. However, the accuracy of these activity trackers in slow walking conditions on a minute-by-minute basis is largely unknown. In this study, the accuracy of a hip-worn commercial activity tracker (FitBit Ultra) was examined through step counts. Accuracy was evaluated through four minute trials of treadmill walking at speeds representative of older adults (0.9, 1.1, and 1.3m/s). Minute-by-minute step count was extracted through the FitBit API and compared it to observer counted steps through video recordings. Results highlighted a significant over-reporting of steps at the highest speed, and a significant under-reporting of steps at the slowest speed, with the FitBit Ultra failing to count steps for one or more minutes at the slowest speed for 11 participants. This study highlights problems with using the FitBit Ultra by slow-walking populations, and recommends that researchers and clinicians should carefully consider the trade-off between accuracy and convenience when using commercial activity trackers with slow-walking populations. [ABSTRACT FROM AUTHOR]

Total knee arthroplasty (TKA) is a standard treatment for patients with end stage knee Osteoarthritis (OA) to reduce pain and restore function. The aim of this study was to assess pre- and early post-operative physical activity (PA) with Fitbit Flex devices for patients with OA undergoing TKA and determine any benchmarks for expected post-operative activity. Significant correlations of pre-operative step count, post-operative step count, Body Mass Index (BMI) and Short Form 12 Physical Component Summaries (SF-12 PCS) were found. Mean step counts varied by 3,203 steps per day between obese and healthy weight patients, and 3,786 steps per day between those with higher and lower SF-12 PCS scores, suggesting the need for benchmarks for recovery that vary by patient pre-operative factors. A backwards stepwise regression model developed to provide patient specific step count predictions at 6 weeks had an R 2 of 0.754, providing a robust patient specific benchmark for post-operative recovery, while population means from BMI and SF-12 subgroups provide a clinically practical alternative. [ABSTRACT FROM AUTHOR]

A small pilot study was conducted to assess synergy between almond ingestion and a walking intervention on cardiovascular health in sedentary adults. Participants (n = 12) followed an 8-week walking protocol (target: 10,000 steps/day), and for study weeks 6–8, participants were randomly assigned to almonds (ALM, 70 g/d) or an isocaloric control butter spread (CON). Protocol adherence was verified by plasma vitamin E measurement. Participant step count increased 23% from baseline levels for weeks 3–5 (p = .015) and remained ≥9800 steps/day for the study duration. Although improvements in cardiovascular health were not demonstrated by the walking protocol alone, total and LDL cholesterol were reduced in the ALM group only during study weeks 6–8 (−6 to −10%; p < .05), and lipid peroxidation tended to fall in the ALM group only as well (−25%; p = .082). These data highlight the value of including almonds in the diet when recommending a walking protocol for improving health. [ABSTRACT FROM AUTHOR]

Background: Smartphone sensors are underutilised in rehabilitation.Objective: To validate the step count algorithm used in the STARFISH smartphone application.Methods: Twenty-two healthy adults (8 male, 14 female) walked on a treadmill for 5 minutes at 0.44, 0.67, 0.90 and 1.33 m⋅s-1. Each wore an activPALTM and four Samsung Galaxy S3TM smartphones, with the STARFISH application running, in: 1) a belt carrycase, 2) a trouser or skirt pocket), 3a) a handbag on shoulder for females or 3b) shirt pocket for males and 4) an upper arm strap. Step counts of the STARFISH application and the activPALTM were compared at corresponding speeds and Bland-Altman statistics used to assess level of agreement (LOA).Results: The LOA between the STARFISH application and activPALTM varied across the four speeds and positions, but improved as speed increased. The LOA ranged from 105-177% at 0.44 m⋅s-1; 50-98% at 0.67 m⋅s-1; 19-67% at 0.9 m⋅s-1 and 8-53% at 1.33 m⋅s-1. The best LOAs were at 1.33 m⋅s-1 in the shirt pocket (8%) and upper arm strap (12%) positions.Conclusions: Step counts measured by the STARFISH smartphone application are valid in most body positions especially at walking speeds of 0.9 m⋅s-1 and above. [ABSTRACT FROM AUTHOR]

This study investigated the relationship between changes in arterial stiffness and the lifestyle habits of endurance athletes after retiring from competition. The subjects were 10 female university endurance athletes. We used form PWV/ ABI® as an index for arterial stiffness and measured brachial-ankle pulse-wave velocity (ba PWV) directly before subjects retired (0Y) and at 2 years after retirement (2Y). Furthermore, to investigate the relationship between arterial stiffness and lifestyle habits 2 years later, Lifecorder ® PLUS was used to measure physical activity levels, hours of sleep were surveyed using a questionnaire, and a food intake survey was conducted using Excel Eiyoukun Food Frequency Questionnaire Based on Food Group, FFQg Ver. 3.5. We found that ba PWV increased significantly from 0Y to 2Y ( P<0·05). Furthermore, negative correlations were observed between 2Y ba PWV and step count as the physical activity index ( r = −0·653, P<0·05) and moderate physical activity ( r = −0·663, P<0·05). With regard to lifestyle habits that affected the amount of increase in ba PWV from 0Y to 2Y (Δba PWV), negative correlations were noted between the step count ( r = −0·690, P<0·05) and total physical activity ( r = −0·657, P<0·05). However, no significant correlations were observed between 2Y ba PWV and Δba PWV with food intake or hours of sleep. The results of this study suggested that physical activity was a lifestyle habit that inhibited an increase in arterial stiffness after retirement from competition and that having a high step count or engaging in physical activity for long periods of time in particular was useful in this regard. [ABSTRACT FROM AUTHOR]

Background and Objectives: The use of smartphones can greatly help for gait parameters estimation during daily living, but its accuracy needs a deeper evaluation against a gold standard. The objective of the paper is a step-by-step assessment of smartphone performance in heel strike, step count, step period, and step length estimation. The influence of smartphone placement and orientation on estimation performance is evaluated as well.Methods: This work relies on a smartphone app developed to acquire, process, and store inertial sensor data and rotation matrices about device position. Smartphone alignment was evaluated by expressing the acceleration vector in three reference frames. Two smartphone placements were tested. Three methods for heel strike detection were considered. On the basis of estimated heel strikes, step count is performed, step period is obtained, and the inverted pendulum model is applied for step length estimation. Pearson correlation coefficient, absolute and relative errors, ANOVA, and Bland-Altman limits of agreement were used to compare smartphone estimation with stereophotogrammetry on eleven healthy subjects.Results: High correlations were found between smartphone and stereophotogrammetric measures: up to 0.93 for step count, to 0.99 for heel strike, 0.96 for step period, and 0.92 for step length. Error ranges are comparable to those in the literature. Smartphone placement did not affect the performance. The major influence of acceleration reference frames and heel strike detection method was found in step count.Conclusion: This study provides detailed information about expected accuracy when smartphone is used as a gait monitoring tool. The obtained results encourage real life applications. [ABSTRACT FROM AUTHOR]

Purpose:Charcot Marie Tooth disease (CMT) describes a group of hereditary neuropathies that present with distal weakness, wasting and sensory loss. Small studies indicate that people with CMT have reduced daily activity levels. This raises concerns as physical inactivity increases the risk of a range of co- morbidities, an important consideration in the long-term management of this disease. This study aimed to compare physical activity, patterns of sedentary behavior and overall energy expenditure of people with CMT and healthy matched controls. Methods:We compared 20 people with CMT and 20 matched controls in a comparison of physical activity measurement over seven days, using an activity monitor. Patterns of sedentary behavior were explored through a power law analysis. Results:Results showed a decrease in daily steps taken in the CMT group, but somewhat paradoxically, they demonstrate shorter bouts of sedentary activity and more frequent transitions from sedentary to active behaviors. No differences were seen in energy expenditure or time spent in sedentary, moderate or vigorous activity. Conclusion:The discrepancy between energy expenditure and number of steps could be due to higher energy requirements for walking, but also may be due to an over-estimation of energy expenditure by the activity monitor in the presence of muscle wasting. Alternatively, this finding may indicate that people with CMT engage more in activities or movement not related to walking.Implications for RehabilitationCharcot-Marie-Tooth disease:• People with Charcot-Marie-Tooth disease did not show a difference in energy expenditure over seven days compared to healthy controls, but this may be due to higher energy costs of walking, and/or an over estimation of energy expenditure by the activity monitor in a population where there is muscle wasting. This needs to be considered when interpreting activity monitor data in people with neuromuscular diseases.• Compared to healthy controls, people with Charcot-Marie-Tooth disease had a lower step count over seven days, but exhibited more frequent transitions from sedentary to active behaviors• High Body Mass Index and increased time spent sedentary were related factors that have implications for general health status.• Understanding the profile of physical activity and behavior can allow targeting of rehabilitation interventions to address mobility and fitness. [ABSTRACT FROM PUBLISHER]

Background and Purpose: Decreasing daily life physical activity (PA) outside an exercise program might hinder the benefit of that program on lower-extremity physical function (LEPF) in older adults. The purpose of this study was to investigate how daily life PA modulates the effects of an exercise program on LEPF. Methods: The participants were 46 community-dwelling older adults (mean age, 70.1 ± 3.5 years) in Kasama City, a rural area in Japan. All participated in a fall-prevention program called square-stepping exercise once a week for 11 weeks. We evaluated their daily life PA outside the exercise program with pedometers and calculated the average daily step counts during the early and late periods of the program. We divided participants into 2 groups on the basis of whether or not they decreased PA by more than 1000 steps per day between the early and late periods. To ascertain the LEPF benefits induced by participating in the exercise program, we measured 5 physical performance tests before and after the intervention: 1-leg stand, 5-time sit-to-stand, Timed Up and Go (TUG), habitual walking speed, and choice-stepping reaction time (CSRT). We used a 2-way analysis of variance to confirm the interaction between the 2 groups and the time effect before and after the intervention. Results: During the exercise program, 8 participants decreased their daily life PA (early period, 6971 ± 2771; late period, 5175 ± 2132) and 38 participants maintained PA (early period, 6326 ± 2477; late period, 6628 ± 2636). Both groups significantly improved their performance in TUG and CSRT at the posttest compared with the baseline. A significant group-by-time interaction on the walking speed (P = .038) was observed: participants who maintained PA improved their performance more than those who decreased their PA. Discussion: Square-stepping exercise requires and strengthens dynamic balance and agility, which contributed to the improved time effects that occurred in TUG and CSRT. On the contrary, because PA is positively associated with walking speed, maintaining daily life PA outside an exercise program may have a stronger influence on walking speed. To enhance the effectiveness of an exercise program for young-old adults, researchers and instructors should try to maintain the participant's daily life PA outside the program. Conclusion: Regardless of decreasing or maintaining daily life PA, the square-stepping exercise program could improve aspects of LEPF that require complex physical performance. However, a greater effect can be expected when participants maintain their daily life PA outside the exercise program. [ABSTRACT FROM AUTHOR]

Objectives To examine dose/response relationships between habitual physical activity and bone health in the elderly. Design Longitudinal. Setting Community of Nakanojo. Participants Community-living Japanese aged 65 to 84 (212 men, 284 women). Measurements Daily 24-h pedometer/accelerometer data were collected continuously for 5 years. A quantitative calcaneal osteosonic index ( OSI) was determined annually. Results Year-end OSI values were higher in those with greater daily step counts and especially a greater duration of activity >3 metabolic equivalents ( METs). However, after controlling for baseline OSI, age and body mass, final OSI values were not significantly greater in the fourth than in the third activity quartile, where men and women, respectively, took means of 7,700 and 7,500 steps/day and/or exercised at an intensity >3 METs for means of 19 and 17 min/day. A multivariate-adjusted proportional hazards model predicted that the OSI values of men and women were, respectively, 2.6 (1.4-4.4) and 3.3 (2.1-5.2) and/or 2.8 (1.5-5.6) and 3.9 (2.4-6.7) times more likely to drop below the OSI fracture threshold over 5 years in the two lowest activity quartiles (<7,000 and <6,900 steps/day and/or <18 and <17 min/day at >3 METs) than in the highest quartile (>9,100 and >8,800 steps/day and/or >30 and >25 min/day at >3 METs). Conclusion After adjustment for potential confounders, the calcaneal health of seniors is associated with both the daily step count and the duration of activity at an intensity >3 METs. The bone health is optimal in elderly people who take at least 7,000-8,000 steps/day and/or spend at least 15-20 min/day at an intensity >3 METs. [ABSTRACT FROM AUTHOR]

Accelerometers have shown great promise and popularity for monitoring gait. However, the accuracy of accelerometers for gait analysis in slow walking conditions is largely unknown. In this study, we compared the accuracy of three accelerometers recommended for gait analysis - Axivity AX3, APDM Opal, and the Actigraph wGT3X-BT, by holding the step-count algorithm constant. We evaluated device accuracy in four minutes of treadmill walking at the speeds of 0.9m/s, 1.1m/s, and 1.3m/s. We constructed a symbolization of the gait data to count the steps using Piecewise Aggregate Approximation and compared the estimated step counts with observer counted steps from video recordings. Our results highlight the variation between the performance of devices - the Axivity AX3 provides more accurate step counts than the other two devices. In this, we provide evidence for future scientific teams to make decisions on selecting accelerometers which can more accurately measure steps taken at slower walking speeds, and suggest ways to improve the design of algorithms and accelerometers. [ABSTRACT FROM AUTHOR]

Reasons for performing study Methods of evaluating locomotor activity can be useful in efforts to quantify behavioural activity in horses objectively. Objectives To evaluate whether an accelerometric device would be adequate to quantify locomotor activity and step frequency in horses, and to distinguish between different levels of activity and different gaits. Study design Observational study in an experimental setting. Methods Dual-mode (activity and step count) piezo-electric accelerometric devices were placed at each of 4 locations (head, withers, forelimb and hindlimb) in each of 6 horses performing different controlled activities including grazing, walking at different speeds, trotting and cantering. Both the activity count and step count were recorded and compared by the various activities. Statistical analyses included analysis of variance for repeated measures, receiver operating characteristic curves, Bland-Altman analysis and linear regression. Results The accelerometric device was able to quantify locomotor activity at each of the 4 locations investigated and to distinguish between gaits and speeds. The activity count recorded by the accelerometer placed on the hindlimb was the most accurate, displaying a clear discrimination between the different levels of activity and a linear correlation to speed. The accelerometer placed on the head was the only one to distinguish specifically grazing behaviour from standing. The accelerometer placed on the withers was unable to differentiate different gaits and activity levels. The step count function measured at the hindlimb was reliable but the count was doubled at the walk. Conclusions The dual-mode accelerometric device was sufficiently accurate to quantify and compare locomotor activity in horses moving at different speeds and gaits. Positioning the device on the hindlimb allowed for the most accurate results. The step count function can be useful but must be manually corrected, especially at the walk. [ABSTRACT FROM AUTHOR]