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Estimation of Gait Independence Using a Tri-Axial Accelerometer in Stroke Patients

Yoshifumi Kijima, Ryoji Kiyama, Masaki Sekine, Toshiyo Tamura, Toshiro Fujimoto, Tetsuo Maeda, and Tadasu Ohshige

patients is usually performed using a three-dimensional motion analysis system and a force plate in the laboratory. However, these methods are not used more frequently in clinical practice because of complications in measurement and data processing ( Krause et al., 2015 ). On the other hand, accelerometers

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Determination of Gait Events Using an Externally Mounted Shank Accelerometer

Jonathan Sinclair, Sarah J. Hobbs, Laurence Protheroe, Christopher J. Edmundson, and Andrew Greenhalgh

Biomechanical analysis requires the determination of specific foot contact events. This is typically achieved using force platform information; however, when force platforms are unavailable, alternative methods are necessary. A method was developed for the determination of gait events using an accelerometer mounted to the distal tibia, measuring axial accelerations. The aim of the investigation was to determine the efficacy of this method. Sixteen participants ran at 4.0 m/s ±5%. Synchronized tibial accelerations and vertical ground reaction forces were sampled at 1000 Hz as participants struck a force platform with their dominant foot. Events determined using the accelerometer, were compared with the corresponding events determined using the force platform. Mean errors of 1.68 and 5.46 ms for average and absolute errors were observed for heel strike and of –3.59 and 5.00 ms for toe-off. Mean and absolute errors of 5.18 and 11.47 ms were also found for the duration of the stance phase. Strong correlations (r = .96) were also observed between duration of stance obtained using the two different methods. The error values compare favorably to other alternative methods of predicting gait events. This suggests that shank-mounted accelerometers can be used to accurately and reliably detect gait events.

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An Accelerometer as an Alternative to a Force Plate for the Step-Up-and-Over Test

Christopher A. Bailey and Patrick A. Costigan

The step-up-and-over test has been used successfully to examine knee function after knee injury. Knee function is quantified using the following variables extracted from force plate data: the maximal force exerted during the lift, the maximal impact force at landing, and the total time to complete the step. For various reasons, including space and cost, it is unlikely that all clinicians will have access to a force plate. The purpose of the study was to determine if the step-up-and-over test could be simplified by using an accelerometer. The step-up-and-over test was performed by 17 healthy young adults while being measured with both a force plate and a 3-axis accelerometer mounted at the low back. Results showed that the accelerometer and force plate measures were strongly correlated for all 3 variables (r = .90–.98, Ps < .001) and that the accelerometer values for the lift and impact indices were 6–7% higher (Ps < .01) and occurred 0.07–0.1 s later than the force plate (Ps < .05). The accelerometer returned values highly correlated to those from a force plate. Compared with a force plate, a wireless, 3-axis accelerometer is a less expensive and more portable system with which to measure the step-up-and-over test.

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The Validity of Gait Variability and Fractal Dynamics Obtained From a Single, Body-Fixed Triaxial Accelerometer

Dylan Kobsar, Chad Olson, Raman Paranjape, and John M. Barden

A single triaxial accelerometer has the ability to collect a large amount of continuous gait data to quantitatively assess the control of gait. Unfortunately, there is limited information on the validity of gait variability and fractal dynamics obtained from this device. The purpose of this study was to test the concurrent validity of the variability and fractal dynamic measures of gait provided by a triaxial accelerometer during a continuous 10 minute walk in older adults. Forty-one healthy older adults were fitted with a single triaxial accelerometer at the waist, as well as a criterion footswitch device before completing a ten minute overground walk. The concurrent validity of six outcome measures was examined using intraclass correlation coefficients (ICC) and 95% limits of agreement. All six dependent variables measured by the accelerometer displayed excellent agreement with the footswitch device. Mean parameters displayed the highest validity, followed by measures of variability and fractal dynamics in stride times and measures of variability and fractal dynamics in step times. These findings suggest that an accelerometer is a valid and unique device that has the potential to provide clinicians with valid quantitative data for assessing their clients’ gait.

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Measuring Physical Activity Levels in People With Mild Cognitive Impairment or Mild Dementia

Veronika van der Wardt, Jennie E. Hancox, Clare Burgon, Rupinder Bajwa, Sarah Goldberg, and Rowan H. Harwood

relies on people’s memories, although, if they are completed on a daily basis, activities might be easier to recall. PA monitors (pedometers and accelerometers) have been used in people with MCI or dementia to support engagement in PA ( Vidoni et al., 2016 ), as well as to measure PA levels in randomized

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A Comparison of Wrist- Versus Hip-Worn ActiGraph Sensors for Assessing Physical Activity in Adults: A Systematic Review

Nolan Gall, Ruopeng Sun, and Matthew Smuck

Physical activity (PA) is an important marker of current health status and a predictor of disease and mortality risk ( Smirnova et al., 2020 ). The use of wearable accelerometers in health and fitness tracking has grown tremendously in recent decades because of their objectivity in daily PA

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Calibrating Physical Activity and Sedentary Behavior for Hip-Worn Accelerometry in Older Women With Two Epoch Lengths: The Women’s Health Initiative Objective Physical Activity and Cardiovascular Health Calibration Study

Kelly R. Evenson, Fang Wen, Christopher C. Moore, Michael J. LaMonte, I-Min Lee, Andrea Z. LaCroix, and Chongzhi Di

Cut points applied to accelerometer output are used to distinguish time spent sedentary from time spent in light and moderate-to-vigorous physical activity (MVPA). The cut points are calibrated for corresponding epoch lengths or short time periods of device signal acquisition. Few accelerometer cut

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Missing Step Count Data? Step Away From the Expectation–Maximization Algorithm

Mia S. Tackney, Daniel Stahl, Elizabeth Williamson, and James Carpenter

Wearable devices, such as pedometers and accelerometers, are becoming a popular tool in clinical and epidemiological studies for measuring participants’ physical activity ( Bravata et al., 2007 ). For example, accelerometers have evaluated the impact of interventions aiming to increase exercise in

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Longitudinal Changes in Moderate to Vigorous Physical Activity in Community-Dwelling Older Men and Women: A 2-Year Prospective Cohort Study in Japan

Tao Chen, Sanmei Chen, Takanori Honda, Yu Nofuji, Hiro Kishimoto, and Kenji Narazaki

10 using accelerometer-derived measures of physical activity have shown that MVPA decreased over 2–3 years of follow-up. Also, few prospective studies have used accelerometer-derived data to examine associated factors of changes in MVPA in older adults over time. To the best of our knowledge, there

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Movement Patterns in Older Adults Recovering From Hip Fracture

Jules J.M. Kraaijkamp, Marjon Stijntjes, Jurriaan H. De Groot, Niels H. Chavannes, Wilco P. Achterberg, and Eléonore F. van Dam van Isselt

( Prince et al., 2014 ). For example, an older adult recovering from hip fracture might receive 30 min of therapy during the morning, but spend the rest of the day sitting. In recent times, the use of wearable activity sensors such as accelerometers have made it possible to obtain a reliable, objective