Name: substantiating appropriate motion capture techniques for the assessment of nordic walking gait and posture in older adults
Uploaded: 2016-05-12T15:00:00.000+00:00
Duration: 9 min 37 s
Description: Watch this Scientific Journal Video about Substantiating Appropriate Motion Capture Techniques for the Assessment of Nordic Walking Gait and Posture in Older Adults at JoVE.com

On behalf of my co-author and myself, I would like to acknowledge Nordixx Canada for helping to fund this research, our participants for their time and patience, and our fellow colleagues, Jos&#233;e, Ria, Lei, and Nadia, for their help with various aspects of this study.

This study was performed in accordance with the guidelines of the Research Ethics Board of the University of Ottawa.
1. Screening Procedure
<ol>
	<li>Provide side show presentations to local area walking groups and post recruitment posters at community centers and public facilities in order to recruit a group of active, community-dwelling older adults.</li>
	<li>Upon initial visit, first greet the participants, introduce them to the laboratory, and provide them time to change into appropriate attire (i.e. shorts, t-shirt, and running shoes). Once ready, provide each participant with an in-depth study description, obtain written informed consent, and screen each individual for study eligibility using various questionnaires. 
	NOTE: Inclusion criteria includes: 55-80 years of age, novice to Nordic walking (NW), no neurological conditions, no cognitive impairments, no cardiac conditions, no previous injury or surgery affecting gait and upper extremity movement, and the ability to walk unaided.
	<ol>
		<li>Have the participant complete a General Health and Physical Activity Questionnaire and the Physical Activity Readiness Questionnaire (PAR-Q) in order to confirm age, activity level, any existing neurological conditions, and briefly assess cardiac health.</li>
		<li>Next, have them complete a self-reported postural stability and falls questionnaire (adapted from Ashburn et al.10) to determine fall prevalence, if applicable. Lastly, complete the Montreal Cognitive Assessment (MOCA) with each subject in order to control for mild cognitive impairment11, constituting a minimum score of 26 out of 30.</li>
	</ol>
	</li>
</ol>
2. Pole Set-up and Nordic Walking Instruction
<ol>
	<li>Provide each participant with a set of poles, and instruct them on how to adjust the poles to an optimal length relative to their height. Ensure that the adjustment corresponds to approximately 65% of the individual&#39;s body height.
	<ol>
		<li>Provide each participant with the following instructions regarding pole adjustment. Ask the participants to stand tall, have the participants place the pole tip in front of the toes, instruct the participants to place the elbow and forearm next to the body, and ask the participants to lengthen the poles so the elbow forms an approximate 90&#176; angle next to the body. Finally, securely tighten the poles and angle the boot tips backwards.</li>
	</ol>
	</li>
	<li>Instruct the participant the following 4 basic steps in order to minimize the amount of information to process and ensure a thorough understanding of technique12. Allot approximately 30 min for instruction and subsequent practice of the technique. 
	NOTE: Nordic walking instructions are to be given by a certified Nordic pole walking instructor.
	<ol>
		<li>Before securing the wrist straps, instruct the participant to place their poles behind the lower back and stand tall. Ask the participants to stand with their chest tall and the shoulders relaxed. 
		NOTE: Explain to the participant that this is done to gain an understanding of the required upright body posture for Nordic walking.</li>
		<li>Have each participant secure the wrist straps, place the pole tips behind them, and relax their arms at their sides. While keeping their hands open (i.e. not grasping handles), instruct the subject to begin walking with minimal arm swing for approximately 100 m. 
		NOTE: At this stage, the poles are simply trailing behind the participant.</li>
		<li>While still keeping the hands open and dragging the poles behind them, instruct the participant to begin walking faster. Ask the participants to visualize bringing their hand up as if they are about to shake someone&#39;s hand. 
		NOTE: At this phase, explain that the goal is to promote the natural reciprocal and rhythmic actions of the arms and legs during gait.</li>
		<li>Finally, as the arm swings forward, have the participant gently grasp the handle and apply a force against the ground. With each arm swing, instruct the individual to slightly lift the poles off the ground and firmly plant them with each subsequent stride. 
		NOTE: At this stage, explain that the applied force aids in progression of gait and provides resistance to the upper body musculature.</li>
	</ol>
	</li>
</ol>
3. Data Collection and Testing Protocol
<ol>
	<li>Using a standard tape measure, weight scale, and caliper, take the participant&#39;s anthropometric measurements, including height, weight, inter-ASIS distance, left and right leg lengths, knee widths, ankle widths, shoulder offsets, elbow widths, wrist widths, and hand thicknesses.
	<ol>
		<li>Using a tape measure, measure each leg length as the distance from the anterior-superior iliac spine (ASIS) to the center of the medial malleolus as well as the distance between the left and right ASIS (i.e. inter-ASIS distance).
		<ol>
			<li>Next, measure the widths of each joint using a caliper by finding the distance between the bony prominences (e.g. condyles) of each joint. Lastly, measure the height and weight of the participant using a standard tape measure and scale, respectively.</li>
		</ol>
		</li>
	</ol>
	</li>
	<li>In order to assess gait patterns (e.g. spatial-temporal measures) and postural alignment over a long period of time, use an accelerometry system for data collection during the 6 Minute Walk Test (6MWT), which is a valid and appropriate test in the assessment of older adult physical endurance13.
	<ol>
		<li>For the accelerometry system, ensure that it is comprised of at least 6 sensors, each with accelerometers and gyroscopes incorporated into them in order to measure both the acceleration (g) and angular velocity (deg/sec) of each specific body segment.
		<ol>
			<li>Prior to placement on the participant, ensure that all sensors are securely docked to the system&#39;s docking station in order to synchronize them and calibrate the system, and ultimately relay precise data measurements14.</li>
		</ol>
		</li>
		<li>Attach the sensors using adjustable hook and loop straps, secure the sensors to the wrists, ankles, lumbar spine (L5) and trunk and collect at a sampling rate of a minimum of 100 Hz.
		<ol>
			<li>When placing the sensors, ensure that they are oriented according to the system guidelines. Position the ankle sensors anteriorly. Position the wrist sensors posteriorly (when in anatomical position). Position the trunk sensor atop the sternum, and position the L5 sensor directly at the L5 vertebrae. 
			NOTE: Kinematic data is wirelessly transmitted from these sensors to an access point, which is used to precisely time the transmission of the synchronized data.</li>
		</ol>
		</li>
		<li>Fit the participant with the 6 sensors and ask them to perform two trials of the 6MWT, one with poles and one without. Randomly assign these two trials to control for order effect.</li>
		<li>Instruct the participant to walk back and forth along a 25 m walkway at a self-selected speed for the 6MWT, for both with and without poles. At this time, be sure to click &#39;Start&#39; to begin data collection with the accelerometry system. 
		NOTE: During pole trials, provide further instruction to the participant to implement their poling instruction.</li>
	</ol>
	</li>
	<li>Finally, assess short duration gait events using a 3-dimensional motion capture system collecting at a minimum of 100 Hz, with two force plates embedded in the pathway. Synchronize the force platforms with the motion capture system, ensure that the force platforms are zeroed to prevent noise in the data, and ensure that they are collecting at a sufficient sampling rate, for example 1,000 Hz.
	<ol>
		<li>Synchronize the force plates to the motion capture system by first connecting them to the computer via the wires provided from the company. Second, directly within the motion capture system software, it is imperative to &#39;add&#39; the force plates to the capture volume by entering the dimensions, sensitivities, sampling rates, and any other required information for the system.</li>
		<li>Ensure that the force plates have been &#39;zeroed&#39;. Do this in two steps: 1) right click on each force plate within the software and select &#39;Zero force plate&#39; and 2) press the &#39;zero&#39; button that is directly on the data acquisition box of the force plates. 
		NOTE: Ensure that the motion capture system collects real-time information from both the left and right legs from foot strikes on each force platform and allows for spatial-temporal, kinematic, and kinetic analysis.</li>
	</ol>
	</li>
	<li>Complete a dynamic calibration of the system (aimed at defining the capture volume that is to be used during data collection). To do this, wave a 3-marker wand in a controlled manner through the capture space. Then perform a static calibration of the system to set the global coordinate system (i.e. reference point of 0, 0, 0 (x, y, z) by placing a 4-marker L-frame at that specified reference point and select &#39;Set Volume&#39; within the computer software. 
	NOTE: The dynamic calibration later assists in the reconstruction of the 3-dimensional position of 39 reflective markers used for this model.
	<ol>
		<li>Fit the participant with the 39 reflective markers, attaching them using double-sided tape and placing them on specific anatomical landmarks including: second metatarsals, lateral malleoli, calcanei, left and right mid-shank, lateral femoral condyles, left and right mid-thigh, ASIS, PSIS, T10, C7, right back, clavicle, sternum, acromion processes, left and right mid-humerus, lateral epicondyles, left and right mid-forearm, medial and lateral wrists, second metacarpals, anterior-lateral head, and posterior-lateral head.</li>
		<li>Instruct the participant to then perform 6 trials of a 5 m walk through the systems capture volume, three with poles and three without. Randomly assign these trials to control for order effect and provide the same instruction as per the 6MWT.</li>
	</ol>
	</li>
</ol>
4. Data and Statistical Analysis14
<ol>
	<li>During analysis of the 6MWT, remove all turns during the trial in order to account for strictly steady state walking After removing the turns, use the system software to extract the spatial-temporal measures, trunk range of motion (ROM) in all places, and trunk velocities in all planes. 
	NOTE: This is done automatically during this protocol through algorithms used by the system itself14. The steps to extract the necessary dependent variables within this system are listed below.
	<ol>
		<li>Using the accelerometry system software, first click on &#39;Monitor Data&#39;, select the appropriate time stamped trials that have been collected, right click on the trials, and select &#39;Convert to CSV&#39;. After doing this, open the CSV file and ensure that data from all 6 sensors has been exported for further analysis.</li>
		<li>Next, select the trial again and click &#39;Export to PDF&#39;. Observe the system generate a PDF report with a number of variables. From here, extract variables that are desired for the study, in this case, spatial-temporal and kinematic measures.</li>
	</ol>
	</li>
	<li>For 3-dimensional motion capture, filter all trials using a fourth-order zero lag Butterworth filter for analog devices with a cut-off frequency of 10 Hz as well as a Woltring filter for the marker trajectories with a 15 mm MSE predicted value. To do this, attach the &#39;Butterworth and Woltring&#39; filtering options to the operations pipeline within the system software, select the aforementioned cut-off frequencies and MSE values, and click &#39;Run&#39;.
	<ol>
		<li>Add an &#39;Export to ASCII file&#39; operation to the operations pipeline within the system and select &#39;Run&#39;. Save the newly exported ASCII (spreadsheet) worksheet to the computer.</li>
		<li>Open the exported ASCII files and within each file, locate the power outputs and moments of force (i.e. kinetics) for each of the lower extremity joints, including the ankle, knee, and hip. 
		NOTE: Using the minimum and maximum functions within the worksheet, calculate the upper and lower peaks corresponding to the different phases of a single gait cycle (e.g. A1, K1, H1, etc.) as outlined by Winter14.</li>
		<li>Next, extract the spatial-temporal measures using the specific system software, which in this instance, is automatically calculated through system algorithms and from anthropometric measurements. To extract the specific variables, first import the desired trial into the system software, select &#39;Events&#39;, and click on the desired variable to obtain the variable average from each trial.</li>
	</ol>
	</li>
	<li>Lastly, using the ASCII files, locate the trajectories for the C7 marker as well as the sacral/pelvic markers. Using these trajectories, calculate postural alignment as the differential between these markers and trajectories in both the medial-lateral and anterior-posterior directions.</li>
	<li>Open statistical software and import the specific trial. First, using Shapiro-Wilks test for normality, ensure whether data is normally distributed.
	<ol>
		<li>To compare with and without poles, use paired t-tests when data is normally distributed and Wilcoxon Signed Rank Tests when skewed. Use Holm-Sidak multiple pairwise comparison procedures when necessary. Significance level is set at p &#60;0.05.</li>
	</ol>
	</li>
</ol>

<ol>
	<li>Parkatti, T., Wacker, P., Perttunen, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Improvements+in+Functional+Capacity+from+Nordic+Walking:+A+Aandomized+Controlled+Trial+Among+Older+Adults.">Improvements in Functional Capacity from Nordic Walking: A Aandomized Controlled Trial Among Older Adults.</a> J Aging Phys Act. 20 (1), 93-105 (2012).</li><li>Schwameder, H., Roithner, R., Muller, E., Niessen, W., Raschner, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Knee+joint+forces+during+downhill+walking+with+hiking+poles.">Knee joint forces during downhill walking with hiking poles.</a> J Sports Sci. 17 (12), 969-978 (1999).</li><li>Willson, J., Torry, M. R., Decker, M. J., Kernozek, T., Steadman, J. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+walking+poles+on+lower+extremity+gait+mechanics.">Effects of walking poles on lower extremity gait mechanics.</a> Med Sci Sports Exerc. 33 (1), 142-147 (2001).</li><li>Koizumi, T., Tsujiuchi, N., Takeda, M., Fujikura, R., Kojima, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Load+dynamics+of+joints+in+Nordic+walking.">Load dynamics of joints in Nordic walking.</a> Procedia Engineering. 13, 544-551 (2011).</li><li>Hansen, L., Henriksen, M., Larsen, P., Alkjaer, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nordic+Walking+does+not+reduce+the+loading+of+the+knee+joint.">Nordic Walking does not reduce the loading of the knee joint.</a> Scand J Med Sci Spor. 18 (4), 436-441 (2008).</li><li>Stief, F., Kleindienst, F. I., Wiemeyer, J., Wedel, F., Campe, S., Krabbe, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Inverse+dynamic+analysis+of+the+lower+extremities+during+Nordic+walking,+walking,+and+running.">Inverse dynamic analysis of the lower extremities during Nordic walking, walking, and running.</a> J Appl Biomech. 24 (4), 351-359 (2008).</li><li>Hagen, M., Hennig, E. M., Stieldorf, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lower+and+upper+extremity+loading+in+nordic+walking+in+comparison+with+walking+and+running.">Lower and upper extremity loading in nordic walking in comparison with walking and running.</a> J Appl Biomech. 27 (1), 22-31 (2011).</li><li>Shim, J., Kwon, H., Kim, H., Kim, B., Jung, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparison+of+the+effects+of+walking+with+and+without+Nordic+pole+on+upper+extremity+and+lower+extremity+muscle+activation.">Comparison of the effects of walking with and without Nordic pole on upper extremity and lower extremity muscle activation.</a> J Phys Ther Sci. 25 (12), 1553-1556 (2013).</li><li>Jensen, S. B., Henriksen, M., Aaboe, J., Hansen, L., Simonsen, E. B., Alkjaer, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Is+it+possible+to+reduce+the+knee+joint+compression+force+during+level+walking+with+hiking+poles.">Is it possible to reduce the knee joint compression force during level walking with hiking poles.</a> Scand J Med Sci Spor. 21 (6), 195-200 (2011).</li><li>Ashburn, A., Hyndman, D., Pickering, R., Yardley, L., Harris, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Predicting+people+with+stroke+at+risk+of+falls.">Predicting people with stroke at risk of falls.</a> Age Ageing. 37 (3), 270-276 (2008).</li><li>Nasreddine, Z. S., Phillips, N. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Montreal+Cognitive+Assessment,+MoCA:+a+brief+screening+tool+for+mild+cognitive+impairment.">The Montreal Cognitive Assessment, MoCA: a brief screening tool for mild cognitive impairment.</a> J Am Geriatr Soc. 53 (4), 695-699 (2005).</li><li>Teaching the Technique. Nordixx Inc Available from: <a target="_blank" href="https://www.nordixx.com/pages/teaching-the-technique/">https://www.nordixx.com/pages/teaching-the-technique/</a> (2015)</li><li>Rikli, R. E., Jones, C. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+reliability+and+validity+of+a+6-minute+walk+test+as+a+measure+of+physical+endurance+in+older+adults.">The reliability and validity of a 6-minute walk test as a measure of physical endurance in older adults.</a> J Aging Phys Activ. 6 (4), 363-375 (1998).</li><li>Winter, D. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biomechanics+and+motor+control+of+human+gait:+normal,+elderly+and+pathological.">Biomechanics and motor control of human gait: normal, elderly and pathological.</a> ISBN. , (1991).</li><li>Winter, D. A., Patla, A. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Signal+processing+and+linear+systems+for+the+movement+sciences.">Signal processing and linear systems for the movement sciences.</a> Waterloo Biomechanics. , (1997).</li><li>Ali, N., Rouhi, G., Robertson, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gender,+vertical+height+and+horizontal+distance+effects+on+single-leg+landing+kinematics:+implications+for+risk+of+non-contact+acl+injury.">Gender, vertical height and horizontal distance effects on single-leg landing kinematics: implications for risk of non-contact acl injury.</a> J Hum Kinet. 37 (1), 27-38 (2013).</li></ol>

This work is funded in part by Nordixx Canada, makers of the walking poles used in this video.

The importance of maintaining consistency in terms of pole use is critical within this protocol. Particularly, appropriate steps for proper poling technique as well as proper pole set up are important to maintain consistency across different studies. Therefore the guidelines and instructions of a specific Nordic walking organization should be adhered to for protocols such as this. Additionally and particularly when using accelerometry, use of a full body set of tri-axial monitors is important to obtain a complete underst...

Nordic walking (NW) is regarded as a simple and safe form of fitness walking using specially designed poles1. It is suggested that poles provide added stability, improve posture, and reduce joint stress of the lower extremities. However, limited or contradictory evidence exists regarding joint loading and postural alignment. On one hand, Schwameder et al.2, Willson et al.3, and Koizumi et al.4 report improvements in kinematic measures and/or reductions in ground reaction, compression, and shear forces with their pole walking studies. On the other hand, declining kinematic measures and increased joint loading in terms of braking/propulsive forces and moments of force have been reported by Hansen et al.5, Stief et al.6, and Hagen et al.7 while pole walking. Additionally, claims of improved postural alignment appear to have gone entirely unsupported by scientific research to this point.
Similar to the contradictory results found with gait patterns, different methods and equipment have been employed in this line of research as well. Several studies have used 3-dimensional motion capture systems4,6 and digital video cameras2,5, all with force plates incorporated into the system, in order to adequately assess gait. While additionally, other studies have employed other means of assessing Nordic poling gait including use of electrogoniometry7, electromyography (EMG)8, and strain gauges mounted to poles2,9. With the technique utilized in this protocol, it presents the specific advantage of being able to demonstrate a more appropriate representation (i.e. repeated gait cycles) of an individual&#39;s Nordic poling gait over alternative techniques that have focused more on short durations and single gait cycles. Also, this method uses accelerometry, a valid tool, which to this point has been sparsely used in Nordic walking research. Depending on the aim of individual research projects, the application of this protocol may be appropriate for situations as outlined in this protocol, particularly for short and long duration gait. It is important to note that both motion capture and accelerometry are suitable for obtaining a variety of gait characteristics including: spatial-temporal (e.g. stride length, gait speed, etc.), kinematic (e.g. range of motion), and kinetic (e.g. forces, power outputs, etc.) parameters.
And despite the use of these various pieces of equipment, only short duration gait events (i.e. single gait cycle) have been assessed, leaving questions in regards to best assessing longer duration gait (i.e. repeated gait cycles). Therefore, the rationale for the development and use of this technique is based upon the importance of fashioning a complete picture of Nordic poling gait.
The purpose of this study was two-fold. First, the primary goal is to determine and substantiate the use of both accelerometry systems and 3-dimensional motion capture systems in the assessment of gait and posture over both short and long durations. Secondarily, the goal is to determine the overall effect of Nordic walking poles on gait patterns including spatial-temporal and kinetic measures as well as postural alignment of older adults. To date, minimal research has focused on older adult NW and of that which has been published, function (i.e. strength, balance, flexibility) has represented the primary outcome variables. Therefore, knowledge pertaining the role of walking poles on measureable gait variables is needed and can provide insight into how poles can play into our gait patterns as we age.

<table><tbody><tr><td>Nordic walking poles</td><td>Nordixx Canada</td><td>Nordixx Global Traveler or Walker</td><td>Alternative poles may be used</td></tr><tr><td>APDM accelerometry system</td><td>APDM</td><td>Opal system</td><td>Alternative systems may be used</td></tr><tr><td>Vicon motion capture system</td><td>Vicon</td><td></td><td>Alternative systems may be used</td></tr><tr><td>Kistler force platforms</td><td>Kistler</td><td></td><td>Alternative platforms may be used</td></tr><tr><td>Vicon Nexus &amp;amp; Polygon</td><td>Vicon</td><td></td><td>Used in data analysis</td></tr><tr><td>14 mm reflective markers</td><td>Vicon</td><td></td><td>Number or markers depends on model</td></tr><tr><td>Tape measure</td><td></td><td></td><td></td></tr><tr><td>Weight scale</td><td></td><td></td><td></td></tr><tr><td>Caliper</td><td></td><td></td><td></td></tr></tbody></table>

substantiating appropriate motion capture techniques for the assessment of nordic walking gait and posture in older adults

Nordic walking (NW) has become a safe and simple form of exercise in recent years, and in studying this gait pattern, various data collection techniques have been employed, each with positives and negatives. The aim was to determine the effect of NW on older adult gait and posture and to determine optimal use of different data collection systems in both short and long duration analysis. Gait and posture during NW and normal walking were assessed in 17 healthy older adults (age: 69 &#177; 7.3). Participants performed two trials of 6 Minute Walk Tests (6MWT) (1 with poles (WP) and 1 without poles (NP)) and 6 trials of a 5m walk (3 WP and 3 NP). Motion was recorded using two systems, a 6-sensor accelerometry system and an 8-camera 3-dimensional motion capture system, in order to quantify spatial-temporal, kinematic, and kinetic parameters.
With both systems, participants demonstrated increased stride length and double support and decreased gait speed and cadence WP compared to NP (p &#60;0.05). Also, with motion capture, larger single support time was found WP (p &#60;0.05). With 3-D capture, smaller hip power generation and moments of force were found at heel contact and pre-swing as well as smaller knee power absorption at heel contact, pre-swing, and terminal swing WP compared to NP, when assessed over one cycle (p &#60;0.05). Also, WP yielded smaller moments of force at heel contact and terminal swing along with larger moments at mid-stance of a gait cycle (p &#60;0.05). No changes were found for posture.
NW seems appropriate for promoting a normal gait pattern in older adults. Three-dimensional motion capture should primarily be used during short duration gait analysis (i.e. single gait cycle), while accelerometry systems should be primarily employed in instances requiring longer duration analysis such as during the 6MWT.

Spatial-Temporal Gait Parameters
When walking with Nordic walking poles and assessed using motion capture and force plates, stride length (p &#60;0.01), double support time (p &#60;0.001), and single support time (p &#60;0.001) are all significantly longer compared to walking without poles. In addition, gait speed (p &#60;0.05) is significantly slower and cadence (p &#60;0.001) is significantly smaller with poles compared to wit...

Watch this Scientific Journal Video about Substantiating Appropriate Motion Capture Techniques for the Assessment of Nordic Walking Gait and Posture in Older Adults at JoVE.com

Substantiating Appropriate Motion Capture Techniques for the Assessment of Nordic Walking Gait and Posture in Older Adults

The aim was to substantiate optimal use of data collection techniques for Nordic walking gait and posture analysis. Three-dimensional motion capture should be used during short duration analysis (i.e. single gait cycle), while accelerometry should be employed for longer duration analysis (i.e. repeated cycles) like a 6 Minute Walk Test.

Nordic walking (NW) has become a safe and simple form of exercise in recent years, and in studying this gait pattern, various data collection techniques ...

substantiating-appropriate-motion-capture-techniques-for-assessment

Universidad San Sebastian

Research

JoVE Journal

Behavior

8.7K Views.  University of Ottawa. The aim was to substantiate optimal use of data collection techniques for Nordic walking gait and posture analysis. Three-dimensional motion capture should be used during short duration analysis (i.e. single gait cycle), while accelerometry should be employed for longer duration analysis (i.e. repeated cycles) like a 6 Minute Walk Test.

Video: Substantiating Appropriate Motion Capture Techniques for the Assessment of Nordic Walking Gait and Posture in Older Adults

Sit-to-stand-and-walk from 120% Knee Height: A Novel Approach to Assess Dynamic Postural Control Independent of Lead-limb

Individuals with sensorimotor pathology e.g., stroke have difficulty executing the common task of rising from sitting and initiating gait (sit-to-walk: STW). Thus, in clinical rehabilitation separation of sit-to-stand and gait initiation - termed sit-to-stand-and-walk (STSW) - is usual. However, a standardized STSW protocol with a clearly defined analytical approach suitable for pathological assessment has yet to be defined.
Hence, a goal-orientated protocol is defined that is suitable for healthy and compromised individuals by requiring the rising phase to be initiated from 120% knee height with a wide base of support independent of lead limb. Optical capture of three-dimensional (3D) segmental movement trajectories, and force platforms to yield two-dimensional (2D) center-of-pressure (COP) trajectories permit tracking of the horizontal distance between COP and whole-body-center-of-mass (BCOM), the decrease of which increases positional stability but is proposed to represent poor dynamic postural control.
BCOM-COP distance is expressed with and without normalization to subjects&#39; leg length. Whilst COP-BCOM distances vary through STSW, normalized data at the key movement events of seat-off and initial toe-off (TO1) during steps 1 and 2 have low intra and inter subject variability in 5 repeated trials performed by 10 young healthy individuals. Thus, comparing COP-BCOM distance at key events during performance of an STSW paradigm between patients with upper motor neuron injury, or other compromised patient groups, and normative data in young healthy individuals is a novel methodology for evaluation of dynamic postural stability.

Here, we present a novel protocol to measure positional stability at key events during the sit-to-stand-to-walk using the center-of-pressure to the whole-body-center-of-mass distance. This was derived from the force platform and three-dimensional motion-capture technology. The paradigm is reliable and can be utilized for the assessment of neurologically compromised individuals.

Individuals with sensorimotor pathology e.g., stroke have difficulty executing the common task of rising from sitting and initiating gait (sit-to-walk: ...

Gait Analysis of Age-dependent Motor Impairments in Mice with Neurodegeneration

Motor behavior tests are commonly used to determine the functional relevance of a rodent model and to test newly developed treatments in these animals. Specifically, gait analysis allows recapturing disease relevant phenotypes that are observed in human patients, especially in neurodegenerative diseases that affect motor abilities such as Parkinson&#39;s disease (PD), Alzheimer&#39;s disease (AD), amyotrophic lateral sclerosis (ALS), and others. In early studies along this line, the measurement of gait parameters was laborious and depended on factors that were hard to control (e.g., running speed, continuous running). The development of ventral plane imaging (VPI) systems made it feasible to perform gait analysis at a large scale, making this method a useful tool for the assessment of motor behavior in rodents. Here, we present an in-depth protocol of how to use kinematic gait analysis to examine the age-dependent progression of motor deficits in mouse models of neurodegeneration; mouse lines with decreased levels of endophilin, in which neurodegenerative damage progressively increases with age, are used as an example.

In this study, we demonstrate the use of kinematic gait analysis based on ventral plane imaging to monitor the subtle changes in motor coordination as well as the progression of neurodegeneration with advancing age in mouse models (e.g., endophilin mutant mouse lines).

Motor behavior tests are commonly used to determine the functional relevance of a rodent model and to test newly developed treatments in these animals. ...

Developmental Biology

Computerized Dynamic Posturography for Postural Control Assessment in Patients with Intermittent Claudication

Computerized dynamic posturography with the EquiTest is an objective technique for measuring postural strategies under challenging static and dynamic conditions. As part of a diagnostic assessment, the early detection of postural deficits is important so that appropriate and targeted interventions can be prescribed. The Sensory Organization Test (SOT) on the EquiTest determines an individual&#39;s use of the sensory systems (somatosensory, visual, and vestibular) that are responsible for postural control. Somatosensory and visual input are altered by the calibrated sway-referenced support surface and visual surround, which move in the anterior-posterior direction in response to the individual&#39;s postural sway. This creates a conflicting sensory experience. The Motor Control Test (MCT) challenges postural control by creating unexpected postural disturbances in the form of backwards and forwards translations. The translations are graded in magnitude and the time to recover from the perturbation is computed.
Intermittent claudication, the most common symptom of peripheral arterial disease, is characterized by a cramping pain in the lower limbs and caused by muscle ischemia secondary to reduced blood flow to working muscles during physical exertion. Claudicants often display poor balance, making them susceptible to falls and activity avoidance. The Ankle Brachial Pressure Index (ABPI) is a noninvasive method for indicating the presence of peripheral arterial disease and intermittent claudication, a common symptom in the lower extremities. ABPI is measured as the highest systolic pressure from either the dorsalis pedis or posterior tibial artery divided by the highest brachial artery systolic pressure from either arm. This paper will focus on the use of computerized dynamic posturography in the assessment of balance in claudicants.

Individuals with intermittent claudication exhibit poor balance compared to healthy controls. Computerized dynamic posturography is an objective method for measuring an individual's postural responses to balance disturbances. This provides an objective reflection of the person&#x2019;s ability to respond to situations under which sensory stimuli are altered and unexpected perturbations occur.

Computerized dynamic posturography with the EquiTest is an objective technique for measuring postural strategies under challenging static and dynamic ...

Medicine

Clinical Assessment of Spatiotemporal Gait Parameters in Patients and Older Adults

Spatial and temporal characteristics of human walking are frequently evaluated to identify possible gait impairments, mainly in orthopedic and neurological patients1-4, but also in healthy older adults5,6. The quantitative gait analysis described in this protocol is performed with a recently-introduced photoelectric system (see&#160;Materials table) which has the potential to be used in the clinic because it is portable, easy to set up (no subject preparation is required before a test), and does not require maintenance and sensor calibration. The photoelectric system consists of series of high-density floor-based photoelectric cells with light-emitting and light-receiving diodes that are placed parallel to each other to create a corridor, and are oriented perpendicular to the line of progression7. The system simply detects interruptions in light signal, for instance due to the presence of feet within the recording area. Temporal gait parameters and 1D spatial coordinates of consecutive steps are subsequently calculated to provide common gait parameters such as step length, single limb support and walking velocity8, whose validity against a criterion instrument has recently been demonstrated7,9. The measurement procedures are very straightforward; a single patient can be tested in less than 5 min&#160;and a comprehensive report can be generated in less than 1&#160;min.

This protocol is used to evaluate spatial and temporal gait variables of neurological/orthopedic patients and older persons by means of a recently-introduced floor-based photocell system.

Spatial and temporal characteristics of human walking are frequently evaluated to identify possible gait impairments, mainly in orthopedic and ...

Walk with Me Hybrid Virtual/In-Person Walking for Older Adults with Neurodegenerative Disease

This study presents a protocol for virtual and in-person walking groups for older adults with neurodegenerative diseases and addresses the decline in physical activity and social connectivity during the pandemic. Physical activity, specifically moderate-intensity walking, has been shown to have multiple health benefits for older adults. This methodology was created during the COVID-19 pandemic, contributing to lower physical activity levels and social isolation in older adults. Both the in-person and virtual classes utilize technology such as fitness tracking apps and video platforms. Data are presented from two groups of older adults with neurodegenerative disease: people with prodromal Alzheimer's disease and people with Parkinson's disease. Participants in the virtual classes were screened for balance impairments before the walk, and any person deemed at risk for falls was not eligible to participate virtually. As COVID vaccines became available and restrictions were lifted, in-person walking groups became feasible. Staff and caregivers were trained in balance management, roles/responsibilities, and delivering walking cues. Both walks, virtual and in-person, consisted of a warm up, a walk, and a cool down, and posture, gait, and safety cues were given throughout. Measures of the rate of perceived exertion (RPE) and heart rate (HR) were taken pre-warm up, post-warm up, and at 15 min, 30 min, and 45 min time points. Participants also used a walking application (app) on their phones to record the distance walked and the number of steps taken. The study showed a positive correlation between HR and RPE in both groups. The participants in the virtual group rated the walking group favorably in terms of improving their quality of life during a period of social isolation and contributing to physical, mental, and emotional well-being. The methodology shows a safe and feasible way to implement virtual and in-person walking groups for older adults with neurological diseases.

The present protocol aims to inform rehabilitation specialists and fitness instructors in safe, feasible, and evidence-based methods of delivering virtual and in-person walking classes to older adults with neurodegenerative diseases.

This study presents a protocol for virtual and in-person walking groups for older adults with neurodegenerative diseases and addresses the decline in ...

Home-Based Monitor for Gait and Activity Analysis

Current outcomes in neuromuscular disorder clinical trials include motor function scales, timed tests, and strength measures performed by trained clinical evaluators. These measures are slightly subjective and are performed during a visit to a clinic or hospital and constitute therefore a point assessment. Point assessments can be influenced by daily patient condition or factors such as fatigue, motivation, and intercurrent illness. To enable home-based monitoring of gait and activity, a wearable magneto-inertial sensor (WMIS) has been developed. This device is a movement monitor composed of two very light watch-like sensors and a docking station. Each sensor contains a tri-axial accelerometer, gyroscope, magnetometer, and a barometer that record linear acceleration, angular velocity, the magnetic field of the movement in all directions, and barometric altitude, respectively. The sensors can be worn on the wrist, ankle, or wheelchair to record the subject&#8217;s movements during the day. The docking station enables data uploading and recharging of sensor batteries during the night. Data are analyzed using proprietary algorithms to compute parameters representative of the type and intensity of the performed movement. This WMIS can record a set of digital biomarkers, including cumulative variables, such as total number of meters walked, and descriptive gait variables, such as the percentage of the most rapid or longest stride that represents the top performance of patient over a predefined period of time.

This innovative device uses magneto-inertial sensors to permit gait and activity analysis in uncontrolled environments. Currently in the qualification process as an outcome measure in the European Medical Agency, one of the applications will be to serve as a clinical endpoint in clinical trials in neuromuscular diseases.

Current outcomes in neuromuscular disorder clinical trials include motor function scales, timed tests, and strength measures performed by trained clinical ...

Bioengineering

Exergaming in Older People Living with HIV Improves Balance, Mobility and Ameliorates Some Aspects of Frailty

Approximately 1.2 million people in the United States live with HIV infection. Medical advancements have increased the life expectancy and this cohort is aging. HIV-positive individuals have a high incidence of frailty (~20%) characterized by depression and sedentary behavior. Exercise would be healthy, but due to the frail status of many HIV-positive individuals, conventional exercise is too taxing. The aim of this study was to evaluate the effectiveness and acceptability of a novel game-based training program (exergame) in ameliorating some aspects of frailty in HIV-infected individuals. Ten older people living with HIV were enrolled in an exergame intervention. Patients performed balance exercises such as weight shifting, ankle reaching, and obstacle crossing. Real-time visual/audio lower-extremity joint motion feedback was provided using wearable sensors to assist feedback and encourage subjects to accurately execute each exercise task. Patients trained twice a week for 45 min for 6 weeks. Changes in balance, gait, psychosocial parameters and quality of life parameters were assessed at the beginning, midterm and at conclusion of the training program. Ten patients completed the study and their results analyzed. The mean age was 57.2 &#177; 9.2 years. The participants showed a significant reduction in center of mass sway (78.2%, p = .045) during the semi-tandem balance stance with eyes closed and showed a significant increase in gait speed during a dual task motor-cognitive assessment (9.3%, p = .048) with an increase in stride velocity of over 0.1 m/sec. A significant reduction in reported pain occurred (43.5%, p = .041). Preliminary results of this exergame intervention show promise in improving balance and mobility while requiring older people living with HIV to be more active. The exergame can be continued at home and may have long term as well as short-term benefits for ameliorating frailty associated with HIV infection.

Persons infected with HIV are often frail, depressed and live a sedentary lifestyle for which conventional exercise is too taxing. Here, we present an exercise protocol that ameliorates aspects of frailty in HIV-infected persons. An exergame integrating cognitive control was developed using biosensors that measured balance, weight-shifting and obstacle crossing.

Approximately 1.2 million people in the United States live with HIV infection. Medical advancements have increased the life expectancy and this cohort is ...

Motor Dual-Tasks for Gait Analysis and Evaluation in Post-Stroke Patients

Eighteen stroke patients were recruited for this study involving the evaluation of cognition and walking ability and multitask gait analysis. Multitask gait analysis consisted of a single walking task (Task 0), a simple motor dual-task (water-holding, Task 1), and a complex motor dual-task (crossing obstacles, Task 2). The task of crossing obstacles was considered to be equivalent to the combination of a simple walking task and a complex motor task as it involved more nervous system, skeletal movement, and cognitive resources. To eliminate heterogeneity in the results of the gait analysis of the stroke patients, the dual-task gait cost values were calculated for various kinematic parameters. The major differences were observed in the proximal joint angles, especially in the angles of the trunk, pelvis, and hip joints, which were significantly larger in the dual motor tasks than in the single walking task. This research protocol aims to provide a basis for the clinical diagnosis of gait function and an in-depth study of motor control in stroke patients with motor control deficits through the analyses of dual-motor walking tasks.

This paper presents a protocol specifically for dual motor task gait analysis in stroke patients with motor control deficits.

Eighteen stroke patients were recruited for this study involving the evaluation of cognition and walking ability and multitask gait analysis. Multitask ...

Neuroscience

Comprehensive Understanding of Inactivity-Induced Gait Alteration in Rodents

It is well known that disuse affects neural systems and that joint motions become altered; however, which outcomes properly exhibit these characteristics is still unclear. The present study describes a motion analysis approach that utilizes three-dimensional (3D) reconstruction from video captures. Using this technology, disuse-evoked alterations of walking performances were observed in rodents exposed to a simulated microgravity environment by unloading their hindlimb by their tail. After 2 weeks of unloading, the rats walked on a treadmill, and their gait motions were captured with four charge-coupled device (CCD) cameras. 3D motion profiles were reconstructed and compared to those of control subjects using the image processing software. The reconstructed outcome measures successfully portrayed distinct aspects of distorted gait motion: hyperextension of the knee and ankle joints and higher position of the hip joints during the stance phase. Motion analysis is useful for several reasons. First, it enables quantitative behavioral evaluations instead of subjective observations (e.g., pass/fail in certain tasks). Second, multiple parameters can be extracted to fit specific needs once the fundamental datasets are obtained. Despite hurdles for broader application, the disadvantages of this method, including labor intensity and cost, may be alleviated by determining comprehensive measurements and experimental procedures.

The present protocol describes three-dimensional motion tracking/evaluation to depict gait motion alteration of rats after exposure to a simulated disuse environment.

It is well known that disuse affects neural systems and that joint motions become altered; however, which outcomes properly exhibit these characteristics ...

Postural Organization of Gait Initiation for Biomechanical Analysis Using Force Platform Recordings

Gait initiation (GI), the transient phase between orthograde posture and steady-state locomotion, is a functional task and an experimental paradigm that is classically used in the literature to obtain insight into the basic postural mechanisms underlying body motion and balance control. Investigating GI has also contributed to a better understanding of the physiopathology of postural disorders in elderly and neurological participants (e.g., patients with Parkinson&#39;s disease). As such, it is recognized to have important clinical implications, especially in terms of fall prevention.
This paper aims to provide scholars, clinicians, and higher education students information on the material and method developed to investigate GI postural organization via a biomechanical approach. The method is based on force platform recordings and the direct principle of mechanics to compute the kinematics of the center of gravity and center of pressure. The interaction between these two virtual points is a key element in this method since it determines the conditions of stability and whole-body progression. The protocol involves the participant initially standing immobile in an upright posture and starting to walk until the end of an at least 5 m track.
It is recommended to vary the GI velocity (slow, spontaneous, fast) and the level of temporal pressure - gait may be initiated as soon as possible after the deliverance of a departure signal (high level of temporal pressure) or when the participant feels ready (low level of temporal pressure). Biomechanical parameters obtained with this method (e.g., duration and amplitude of anticipatory postural adjustments, step length/width, performance, and stability) are defined, and their computation method is detailed. In addition, typical values obtained in healthy young adults are provided. Finally, critical steps, limitations, and significance of the method with respect to the alternative method (motion capture system) are discussed.

This paper describes the material and method developed to investigate the postural organization of gait initiation. The method is based on force platform recordings and on the direct principle of mechanics to compute center of gravity and center of pressure kinematics.

Gait initiation (GI), the transient phase between orthograde posture and steady-state locomotion, is a functional task and an experimental paradigm that ...