This study sponsored by the National Natural Science Foundation of China (81772423), K. C. Wong Magna Fund in Ningbo University, and the National Key R&#38;D Program of China (2018YFF0300903).

Written informed consent was obtained from subjects and the testing procedures were approved by the university ethics committee. All participants were informed of the requirements and process of the trial.
1. Laboratory preparation
<ol>
	<li>During calibration, switch off the lights and remove other possibly reflective objects. Ensure that eight cameras are appropriately placed and have a clear view without re&#64258;ection.</li>
	<li>Open the Vicon Nexus 1.8.5 program, and then initialize the cameras. Select System | Local System | MX Cameras in the Resources pane and the cameras will engage. 
	NOTE: In the Properties pane, the parameters need to be adjusted. The range of values of the strobe intensity are adjusted to 0.95-1, and the value range of the threshold is set to 0.2-0.4. Set the grayscale mode to Auto. The Minimum circularity ratio is set to 0.5, and the Gain to times 1 (x1), the Max blob height to 50, and select Enable LEDs.</li>
	<li>Place the T-frame in the center of the capture area, select all the cameras in the system, and use 2D mode. Confirm that the T-frame is in the camera view without any interference points. Select the first item System Preparation in the toolbar. In the T-Frame drop-down list, select the 5 Marker Wand &#38; T-Frame calibration object.</li>
	<li>In the System Preparation Tools pane, click the Start button under the Mask Cameras section. Then click the Start button under Calibrate MX camera section. 
	NOTE: When the calibration process is completed, the progress bar is restored to 0%.</li>
	<li>Place the T-frame in the center of the camera to establish the origin of the coordinates.</li>
	<li>In the Tool pane, click the Start button under the Set Volume Origin section.</li>
	<li>Put the treadmill in the center of the test zone. The eight cameras are displayed around the treadmill (Figure 1).</li>
	<li>Attach a total of 22 reflective markers (diameter: 14 mm) with double-sided tape on the subjects in advance.</li>
</ol>
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/61192/61192fig1.jpg" /> 
Figure 1: Test site layout. Cameras capture lower-limb motion while the subjects run on the treadmill. <a href="https://www.jove.com/files/ftp_upload/61192/61192fig1large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
2. Subject preparation
<ol>
	<li>Before the test, interview subjects in the laboratory and give a simple explanation of the experimental procedures. Then, have the participants complete a questionnaire. Summarize the results of these questionnaires.
	<ol>
		<li>Use the following questions:
		<ol>
			<li>How often do you run in a week?</li>
			<li>How many years have you been running for?</li>
			<li>Have you suffered any lower extremity injuries or received lower extremity surgeries in the last six months?</li>
			<li>How many kilometers do you run per week?</li>
		</ol>
		</li>
	</ol>
	</li>
	<li>Use the following inclusion criteria: all participants were right leg dominant and without any lower extremity injuries in the previous six months before the study. All participants ran at least 15 km per week. 
	NOTE: Ten healthy recreational female runners (ages: 23.4&#177;1.3 years; height: 160.7&#177;3.8 cm; mass: 50.3&#177;2.3 kg; running years: 3.2&#177;1.2 years) were selected.
	<ol>
		<li>Obtain written informed consent from participants who meet the inclusion criteria.</li>
	</ol>
	</li>
	<li>Require that participants wear uniform tights and pants.</li>
	<li>Record the subjects&#8217; height (mm), weight (kg), lower limb length (mm), knee width (mm) and ankle width (mm) for the statistics model.</li>
	<li>Place 16 reflective markers on subjects at the following locations: anterior-superior iliac spine, posterior-superior iliac spine, lateral mid-thigh, lateral knee, lateral mid-shank, lateral malleolus, second metatarsal head, and calcaneus. Place the markers on the second metatarsal head and calcaneus on the corresponding anatomical points of the socks and shoes.</li>
	<li>Instruct the participants to wear uniform sport running shoes. Have the participants warm up with light running and stretching for 5 min.</li>
</ol>
3. Static calibration
<ol>
	<li>Click the Data Management button on the toolbar, select Data Management. Click the New Database tab on the toolbar, select the location, describe the trial name and the Clinical Template, and click the create button.</li>
	<li>In the Open Database window, select the name of the database that was created. In the open interface, click the green New Patient Classification button, the yellow New Patient button, and the grey New session button to create the experimental information including subject type, subject name, and different action status.
	<ol>
		<li>Go back to the Nexus pane, in the left toolbar, click Subjects to create a New Subject data set, and choose the trial model. In the Properties pane, fill in all the anthropometric measurements: height (mm), weight (kg), lower limb length (mm), knee width (mm) and ankle width (mm).</li>
	</ol>
	</li>
	<li>Click the Go live button, select Spilt horizontally and choose the graph to check the Trajectory count. 
	NOTE: Ensure that all the markers are visible in the 3D Perspective view. This indicates that all markers can be captured for analysis.</li>
	<li>Prepare to capture the static model. On the Capture Tools pane, click the Start button in the Subject Capture section. 
	NOTE: During the whole data collection process, the subjects should remain stationary in the capture area to collect 140-200 frames of images. Then click the Stop button.</li>
	<li>In the perspective pane, view the capture marks. Click the Pipeline button in the Tools pane, select Running The Reconstruct Pipeline to create a 3D image of the captured markers. Then, manually label the static model. When the identification is completed, save and press ESC to exit.</li>
	<li>In the toolbar, choose the subject preparation and subject calibration. Select the Static plug-in gait option from the drop-down list. In the Static Settings pane, choose the left foot and right foot, click the start button and save the static model.</li>
</ol>
4. Dynamic trials
<ol>
	<li>When finished collecting the static data, select Capture in the right toolbar. Choose Trial Type and Session from top to bottom, and fill in the trial description.</li>
	<li>Ask participants to run on the treadmill in the following manner.
	<ol>
		<li>Warm up by walking at 8 km/h for 1 min.</li>
		<li>Ask the participant to run on the treadmill at speed of 10 km/h. After an adaption period of 4 min at this velocity, record the running data for 40 s. Collect the kinematic data at a distance of 0.5 km and 5 km, respectively.</li>
		<li>Ask the subjects to wear a heart rate monitor to record the heart rate and monitor the subjects&#8217; fatigue status while running.</li>
	</ol>
	</li>
	<li>In the Tool Capture pane, click the Start button. After collecting the dynamic trials, click Stop to end the collection.</li>
</ol>
5. Post-processing
<ol>
	<li>Open the Data Management window, double-click the trial name. Click the run Reconstruct Pipeline and Labels button in the toolbar to reconstruct the mark point position.</li>
	<li>In the Perspective window, move the blue triangles on the time bar to set the required range of time.</li>
	<li>Shift the view of the timeline so that it shows only the selected range, click on the time bar, and click Zoom to Region-of-Interest.</li>
	<li>At this point, select the Label button to identify and check the label points, with the same steps as the static identification process. If necessary, supplement some incomplete identification points. Delete the unlabeled marks.</li>
	<li>In the Subject Calibration pane, select the Dynamic Plug-in Gait. Click the Start button to run the data. Export motorial trials in c3d format for post-processing.</li>
</ol>
6. Data analysis
<ol>
	<li>Process the kinematics data. Apply a fourth-order low pass Butterworth filter with a cut off frequency of 10 Hz (kinematic) before exporting the joint angle data. Export the data of the joint angle.</li>
	<li>Calculate the range of motion (ROM), peak angle and peak angular velocity of the lower limb joints (hip, knee, and ankle) in three planes (sagittal, frontal, and transverse) during one stance phase.</li>
</ol>
7. Statistical analysis
<ol>
	<li>Use paired-sample T-test to compare lower limb kinematics (peak angles, ROM, peak angular velocity) between the initial (IR) and terminal phase (TR) of 5 km running.</li>
	<li>Calculate mean values and standard deviations of the five valid trials from each subject for different running distances. Set the significance level at p &#60; 0.05.</li>
</ol>

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No potential conflict of interest was reported by the authors.

This study compared the effect of long distance running on the biomechanical characteristics of the lower extremity in amateur runners. It was found that the peak angle of ankle eversion and knee abduction increased after 5 km running, which is consistent with a previous study17. Studies have shown that excessive ankle eversion and eversion velocity are important factors that increase the risk of ankle injuries18,19. It is not surprising t...

Running is the most popular sport around the world. There are a large number of individuals that run and this number increases substantially every year1. It has been suggested that participation in regular exercise including running can promote health, reduce the risk of cardiovascular diseases and thus improve life expectancy2,3,4. Despite the significant health benefits of running, the incidence of running injuries has increased from 25% to 83% over the years5,6. There are some risks associated with running, especially to the lower extremities, which are mainly focused on musculoskeletal injuries7. The majority of common running-related injuries are related to patellofemoral pain, ankle sprain, tibial stress fractures, and plantar fasciitis8. Running injuries can be induced by many factors, such as incorrect foot striking patterns, incorrect shoe selection, and other individual biomechanical factors9. For instance, running with a heel-strike pattern can lead to greater pronation, and is accompanied by larger plantar pressure on the medial side of foot, which may lead a higher risk for Achilles tendinopathy and patellofemoral pain10. In addition, running with a greater knee internal rotation has been previously reported to be associated with the iliotibial band syndrome for female runners11, especially when running long distances.
Parameters of kinetics, kinematics, and time-space components can provide a precise analysis of gait biomechanics, and is currently considered to be an important parameter for clinical gait analysis12. Lower vertical ground reaction forces and larger impact accelerations are recoded after long-distance running13,14. Higher hip excursion and smaller knee flexions have also been found along with fatigued muscles15, and the increased stride frequency can result in reduced stride lengths13,16.
However, changes in biomechanical features of lower limbs at the phase of initial and terminal running have not been fully analyzed, since most studies measured biomechanical variation after running. Additionally, only a few studies use standard laboratory techniques to assess the effects of long-distance running on gait biomechanical changes in amateur runners. The main factors leading to running injuries are still unclear. Therefore, in order to reveal the underlying reasons for lower extremity injuries caused by long distance running, this study aims to compare the biomechanical changes of the lower extremity between the IR and TR phases in treadmill 5 km running in amateur runners.

<table border="0" cellpadding="0" cellspacing="0" style="width:659px;" width="657">
	<colgroup>
		<col />
		<col span="2" />
		<col />
	</colgroup>
	<tbody>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">14 mm Diameter Passive Retro-reflective Marker</td>
			<td style="width:111px;">Oxford Metrics Ltd., Oxford, UK</td>
			<td style="width:111px;"></td>
			<td style="width:221px;">n=22</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:22px;width:216px;">Double Adhesive Tape</td>
			<td style="width:111px;">Oxford Metrics Ltd., Oxford, UK</td>
			<td style="width:111px;"></td>
			<td>For fixing markers to skin</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Heart Rate</td>
			<td style="width:111px;">Garmin, HRM3-SS, China</td>
			<td style="width:111px;"></td>
			<td>Detection of fatigue state</td>
		</tr>
		<tr height="24">
			<td height="24" style="height:24px;width:216px;">Motion Tracking Cameras</td>
			<td style="width:111px;">Oxford Metrics Ltd., Oxford, UK</td>
			<td style="width:111px;"></td>
			<td>n= 8</td>
		</tr>
		<tr height="22">
			<td height="22" style="height:23px;width:216px;">T-Frame</td>
			<td style="width:111px;">Oxford Metrics Ltd., Oxford, UK</td>
			<td style="width:111px;"></td>
			<td>-</td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:216px;">Treadmill</td>
			<td style="width:111px;">Smart Run,China</td>
			<td style="width:111px;"></td>
			<td style="width:221px;">Subject run on the treadmill for all the process.</td>
		</tr>
		<tr height="22">
			<td height="22" style="height:23px;width:216px;">Valid Dongle</td>
			<td style="width:111px;">Oxford Metrics Ltd., Oxford, UK</td>
			<td style="width:111px;"></td>
			<td>Vicon Nexus 1.4.116</td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;">Vicon Datastation ADC</td>
			<td style="width:111px;">Oxford Metrics Ltd., Oxford, UK</td>
			<td style="width:111px;"></td>
			<td>-</td>
		</tr>
	</tbody>
</table>

comparative analysis of lower limb kinematics between the initial and terminal  phase  of 5km treadmill running

Running is beneficial for physical health, but it is also accompanied by many injuries. However, the main factors leading to running injury remain unexplained. This study investigated the effects of long running distance on lower-limb kinematic variables and the lower limb kinematic difference of between the initial (IR) and terminal phase (TR) of 5 km running was compared. Ten amateur runners ran on a treadmill at the speed of 10 km/h. Dynamic kinematic data was collected at the phase of IR (0.5 km) and TR (5 km), respectively. The peak angle, peak angular velocities, and range of motion were recorded in this experiment. The main results demonstrated the following: ankle eversion and knee abduction were increased at TR; ROMs of ankle and knee were increased in the frontal plane at TR than IR; a larger peak angular velocity of ankle dorsiflexion and hip interrotation were found in TR compared to IR. These changes during the long distance running may provide some specific details for exploring potential reasons of running injuries.

The results showed that no differences in the peak angle of the ankle and hip were observed in the sagittal plane. Compared with IR, the peak angles of the ankle and the knee in the frontal plane were significantly increased at TR. A larger internal hip angle was found in TR as contrasted to IR. However, TR presented a smaller peak angle in hip abduction, ankle interrotation, and knee interrotation than IR (Figure 2).
In the sagittal plane, the ROMs of the ankle a...

Watch this Scientific Journal Video about Comparative Analysis of Lower Limb Kinematics between the Initial and Terminal  Phase  of 5km Treadmill Running at JoVE.com

Comparative Analysis of Lower Limb Kinematics between the Initial and Terminal  Phase  of 5km Treadmill Running

This study investigated the biomechanical characteristics of the lower extremity kinematic variables between the initial and terminal phase of 5 km treadmill running. The lower-limb kinematic data of 10 runners were collected using a three-dimensional motion capture system on a treadmill at the initial phase (0.5 km) and the terminal phase (5 km), respectively.

Running is beneficial for physical health, but it is also accompanied by many injuries. However, the main factors leading to running injury remain ...

comparative-analysis-lower-limb-kinematics-between-initial-terminal

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6.0K Views.  Ningbo University. This study investigated the biomechanical characteristics of the lower extremity kinematic variables between the initial and terminal phase of 5 km treadmill running. The lower-limb kinematic data of 10 runners were collected using a three-dimensional motion capture system on a treadmill at the initial phase (0.5 km) and the terminal phase (5 km), respectively.

Video: Comparative Analysis of Lower Limb Kinematics between the Initial and Terminal  Phase  of 5km Treadmill Running

Assessing Forelimb Function after Unilateral Cervical SCI using Novel Tasks: Limb Step-alternation, Postural Instability and Pasta Handling

Cervical spinal cord injury (cSCI) can cause devastating neurological deficits, including impairment or loss of upper limb and hand function. A majority of the spinal cord injuries in humans occur at the cervical levels. Therefore, developing cervical injury models and developing relevant and sensitive behavioral tests is of great importance. Here we describe the use of a newly developed forelimb step-alternation test after cervical spinal cord injury in rats. In addition, we describe two behavioral tests that have not been used after spinal cord injury: a postural instability test (PIT), and a pasta-handling test. All three behavioral tests are highly sensitive to injury and are easy to use. Therefore, we feel that these behavioral tests can be instrumental in investigating therapeutic strategies after cSCI.

Three new behavioral tests (forelimb step-alternation, postural instability test, pasta handling test) for evaluating forelimb function after cervical spinal cord injury in rodents are described.

Cervical spinal cord injury (cSCI) can cause devastating neurological deficits, including impairment or loss of upper limb and hand function. A majority ...

A Mouse Model of Subchronic and Mild Social Defeat Stress for Understanding Stress-induced Behavioral and Physiological Deficits

Stressful life events often increase the incidence of depression in humans. To study the mechanisms of depression, the development of animal models of depression is essential. Because there are several types of depression, various animal models are needed for a deeper understanding of the disorder. Previously, a mouse model of subchronic and mild social defeat stress (sCSDS) using a modified chronic social defeat stress (CSDS) paradigm was established. In the paradigm, to reduce physical injuries from aggressors, the duration of physical contact between the aggressor and a subordinate was reduced compared to in the original CSDS paradigm. sCSDS mice showed increased body weight gain, food intake, and water intake during the stress period, and their social behaviors were suppressed after the stress period. In terms of the face validity of the stress-induced overeating and overdrinking following the increased body weight gain, the sCSDS mice may show some features related to atypical depression in humans. Thus, a mouse model of sCSDS may be useful for studying the pathogenic mechanisms underlying depression. This protocol will help establish the sCSDS mouse model, especially for studying the mechanisms underlying stress-induced weight gain and polydipsia- and hyperphagia-like symptoms.

Here, methods for developing a mouse model of subchronic and mild social defeat stress are described and used to investigate the pathogenic features of depression including hyperphagia- and polydipsia-like symptoms following increased body weight.

Stressful life events often increase the incidence of depression in humans. To study the mechanisms of depression, the development of animal models of ...

Testing Tactile Masking between the Forearms

Masking, in which one stimulus affects the detection of another, is a classic technique that has been used in visual, auditory, and tactile research, usually using stimuli that are close together to reveal local interactions. Masking effects have also been demonstrated in which a tactile stimulus alters the perception of a touch at a distant location. Such effects can provide insight into how components of the body's representations in the brain may be linked. Occasional reports have indicated that touches on one hand or forearm can affect tactile sensitivity at corresponding contralateral locations. To explore the matching of corresponding points across the body, we can measure the spatial tuning and effect of posture on contralateral masking. Careful controls are required to rule out direct effects of the remote stimulus, for example by mechanical transmission, and also attention effects in which thresholds may be altered by the participant's attention being drawn away from the stimulus of interest. The use of this technique is beneficial as a behavioural measure for exploring which parts of the body are functionally connected and whether the two sides of the body interact in a somatotopic representation. This manuscript describes a behavioural protocol that can be used for studying contralateral tactile masking.

Here we explore contralateral tactile masking between the forearms in which tactile detection thresholds are modulated by vibration applied to a remote site. The details of which remote sites have an effect can tell us about how the body is represented in the brain.

Masking, in which one stimulus affects the detection of another, is a classic technique that has been used in visual, auditory, and tactile research, ...

The Treadmill Fatigue Test: A Simple, High-throughput Assay of Fatigue-like Behavior for the Mouse

Fatigue is a prominent symptom in many diseases and disorders and reduces quality of life for many people. The lack of clear pathogenesis and failure of current interventions to adequately treat fatigue in all patients leaves a need for new treatment options. Despite the therapeutic need and importance of preclinical research in helping identify promising novel treatments, few preclinical assays of fatigue are available. Moreover, the most common preclinical assay used to assess fatigue-like behavior, voluntary wheel running, is not suitable for use with some strains of mice, may not be sensitive to drugs that reduce fatigue, and has relatively low throughput. The current protocol describes a novel, non-voluntary preclinical assay of fatigue-like behavior, the treadmill fatigue test, and provides evidence of its efficacy in detecting fatigue-like behavior in mice treated with a chemotherapy drug known to cause fatigue in humans and fatigue-like behavior in animals. This assay may be a beneficial alternative to wheel running, as fatigue-like behavior and potential interventions can be assessed in a greater number of mice over a shorter time frame, thus permitting faster discovery of new therapeutic options.

Fatigue is a common, undertreated and frequently poorly-understood symptom in many diseases and disorders. New preclinical assays of fatigue may help to improve current understanding and future treatment of fatigue. To that end, the current protocol provides a novel means of measuring fatigue-like behavior in the mouse.

Fatigue is a prominent symptom in many diseases and disorders and reduces quality of life for many people. The lack of clear pathogenesis and failure of ...

Using a Split-belt Treadmill to Evaluate Generalization of Human Locomotor Adaptation

Understanding the mechanisms underlying locomotor learning helps researchers and clinicians optimize gait retraining as part of motor rehabilitation. However, studying human locomotor learning can be challenging. During infancy and childhood, the neuromuscular system is quite immature, and it is unlikely that locomotor learning during early stages of development is governed by the same mechanisms as in adulthood. By the time humans reach maturity, they are so proficient at walking that it is difficult to come up with a sufficiently novel task to study de novo locomotor learning. The split-belt treadmill, which has two belts that can drive each leg at a different speed, enables the study of both short- (i.e., immediate) and long-term (i.e., over minutes-days; a form of motor learning) gait modifications in response to a novel change in the walking environment. Individuals can easily be screened for previous exposure to the split-belt treadmill, thus ensuring that all experimental participants have no (or equivalent) prior experience. This paper describes a typical split-belt treadmill adaptation protocol that incorporates testing methods to quantify locomotor learning and generalization of this learning to other walking contexts. A discussion of important considerations for designing split-belt treadmill experiments follows, including factors like treadmill belt speeds, rest breaks, and distractors. Additionally, potential but understudied confounding variables (e.g., arm movements, prior experience) are considered in the discussion.

We describe a protocol for investigating human locomotor adaptation using the split-belt treadmill, which has two belts that can drive each leg at a different speed. We specifically focus on a paradigm designed to test the generalization of adapted locomotor patterns to different walking contexts (e.g., gait speeds, walking environments).

Understanding the mechanisms underlying locomotor learning helps researchers and clinicians optimize gait retraining as part of motor rehabilitation. ...

Using Gold-standard Gait Analysis Methods to Assess Experience Effects on Lower-limb Mechanics During Moderate High-heeled Jogging and Running

A limited number of studies have explored lower-limb biomechanics during high-heeled jogging and running, and most studies have failed to clarify the wearing experience of subjects. This protocol describes the differences in lower-limb kinematics and ground reaction force (GRF) between experienced wearers (EW) and inexperienced wearers (IEW) during moderate high-heeled jogging and running. A three-dimensional (3D) motion analysis system with a configured force platform was used to synchronously capture lower-limb joint movements and GRF. 36 young females volunteered to participate in this study and were asked about high-heeled shoe-wearing experience, including frequency, duration, heel types, and heel heights. Eleven who had the experience of 3 to 6 cm heels for a minimum of three days per week (6 h per day) for at least two years and eleven who wore high heels less than twice per month participated. Subjects performed jogging and running at comfortable low and high speeds, respectively, with the right foot completely stepping onto a force platform when passing by along a 10 m walkway. EW and IEW adopted different biomechanical adaptations while jogging and running. IEW exhibited a generally larger range of joint movement, while EW showed a dramatically larger loading rate of GRF during running. Hence, further studies on the lower-limb biomechanics of high-heeled gait should strictly control the wearing experience of the subjects.

This study investigated lower-limb kinematics and ground reaction force (GRF) during moderate high-heeled jogging and running. Subjects were divided into groups of experienced wearers and inexperienced wearers. A three-dimensional motion analysis system with a configured force platform captured lower-limb joint movements and GRF.

A limited number of studies have explored lower-limb biomechanics during high-heeled jogging and running, and most studies have failed to clarify the ...

Paradigms of Lower Extremity Electrical Stimulation Training After Spinal Cord Injury

Skeletal muscle atrophy, increased adiposity and reduced physical activity are key changes observed after spinal cord injury (SCI) and are associated with numerous cardiometabolic health consequences. These changes are likely to increase the risk of developing chronic secondary conditions and impact the quality of life in persons with SCI. Surface neuromuscular electrical stimulation evoked resistance training (NMES-RT) was developed as a strategy to attenuate the process of skeletal muscle atrophy, decrease ectopic adiposity, improve insulin sensitivity and enhance mitochondrial capacity. However, NMES-RT is limited to only a single muscle group. Involving multiple muscle groups of the lower extremities may maximize the health benefits of training. Functional electrical stimulation-lower extremity cycling (FES-LEC) allows for the activation of 6 muscle groups, which is likely to evoke greater metabolic and cardiovascular adaptation. Appropriate knowledge of the stimulation parameters is key to maximizing the outcomes of electrical stimulation training in persons with SCI. Adopting strategies for long-term use of NMES-RT and FES-LEC during rehabilitation may maintain the integrity of the musculoskeletal system, a pre-requisite for clinical trials aiming to restore walking after injury. The current manuscript presents a combined protocol using NMES-RT prior to FES-LEC. We hypothesize that muscles conditioned for 12 weeks prior to cycling will be capable of generating greater power, cycle against higher resistance and result in greater adaptation in persons with SCI.

Spinal cord injury is a traumatic medical condition that may result in elevated risks of chronic secondary metabolic disorders. Here, we presented a protocol using surface neuromuscular electrical stimulation-resistance training in conjunction with functional electrical stimulation-lower extremities cycling as a strategy to ameliorate several of these medical problems.

Skeletal muscle atrophy, increased adiposity and reduced physical activity are key changes observed after spinal cord injury (SCI) and are associated with ...

A Simple Non-invasive Method for Temporary Knockdown of Upper Limb Proprioception

Proprioception may be the least well measured of all contributors to the neural control of movement. New precise, reliable measures of proprioception are needed for clinical diagnosis of impairment, and to measure outcomes of proprioceptive training. The purpose of this simple, non-invasive method is to temporarily knockdown upper limb proprioception in healthy adults, to an extent that would be useful in the development and testing of upper limb proprioception measures. Knockdown models have two main advantages over studying humans with impaired proprioception: participant availability and the ability to control the extent of impairment across participants. Current published methods of temporary proprioception knockdown of the upper limb, such as ischemic nerve blocks and cryotherapy, are invasive, impractical, or uncomfortable for the participant. Here, vibration over the ulnar groove was used to reduce upper limb proprioception. High frequency vibration may reduce proprioceptive acuity by inhibiting pacinian corpuscle-induced input. The effect of vibration used in this protocol was confirmed using two quantitative measures. This method was simple to administer, comfortable for participants, and practical.

The goal of this protocol is to demonstrate a practical method to temporarily interfere with proprioception in the upper limb of healthy humans.

Proprioception may be the least well measured of all contributors to the neural control of movement. New precise, reliable measures of proprioception are ...

Measuring the Kinematics of Daily Living Movements with Motion Capture Systems in Virtual Reality

The inability to complete instrumental activities of daily living (IADL) is a precursor to various neuropsychological diseases. Questionnaire-based assessments of IADL are easy to use but prone to subjective bias. Here, we describe a novel virtual reality (VR) test to assess two complex IADL tasks: handling financial transactions and using public transportation. While a participant performs the tasks in a VR setting, a motion capture system traces the position and orientation of the dominant hand and head in a three-dimensional Cartesian coordinate system. Kinematic raw data are collected and converted into &#39;kinematic performance measures,&#39; i.e., motion trajectory, moving distance, and time to completion. Motion trajectory is the path of a particular body part (e.g., dominant hand or head) in space. Moving distance refers to the total distance of the trajectory, and time to completion is how long it took to complete an IADL task. These kinematic measures could discriminate patients with cognitive impairment from healthy controls. The development of this kinematic measuring protocol allows detection of early IADL-related cognitive impairments.

We designed a virtual reality test to assess instrumental activities of daily living (IADL) with a motion capture system. We propose a detailed kinematic analysis to interpret the participant&#39;s various movements, including trajectory, moving distance, and time to completion to evaluate IADL capabilities.

The inability to complete instrumental activities of daily living (IADL) is a precursor to various neuropsychological diseases. Questionnaire-based ...

Short Session High Intensity Interval Training and Treadmill Assessment in Aged Mice

High intensity interval training (HIIT) is emerging as a therapeutic approach to prevent, delay, or ameliorate frailty. In particular short session HIIT, with regimens less than or equal to 10 min is of particular interest as several human studies feature routines as short as a few minutes a couple times a week. However, there is a paucity of animal studies that model the impacts of short session HIIT. Here, we describe a methodology for an individually tailored and progressive short session HIIT regimen of 10 min given 3 days a week for aged mice using an inclined treadmill. Our methodology also includes protocols for treadmill assessment. Mice are initially acclimatized to the treadmill and then given baseline flat and uphill treadmill assessments. Exercise sessions begin with a 3 min warm-up, then three intervals of 1 min at a fast pace, followed by 1 min at an active recovery pace. Following these intervals, the mice are given a final segment that starts at the fast pace and accelerates for 1 min. The HIIT protocol is individually tailored as the speed and intensity for each mouse are determined based upon initial anaerobic assessment scores. Additionally, we detail the conditions for increasing or decreasing the intensity for individual mice depending on performance. Finally, intensity is increased for all mice every two weeks. We previously reported in this protocol enhanced physical performance in aged male mice and here show it also increases treadmill performance in aged female mice. Advantages of our protocol include low administration time (about 15 min per 6 mice, 3 days a week), strategy for individualizing for mice to better model prescribed exercise, and a modular design that allows for the addition or removal of the number and length of intervals to titrate exercise benefits.

Short session (&#8804;10 min) high intensity interval training (HIIT) is emerging as an alternative to longer exercise modalities, yet the shorter variants are rarely modeled in animal studies. Here, we describe a 10 min, 3 day a week, uphill treadmill HIIT protocol that enhances physical performance in male and female aged mice.

High intensity interval training (HIIT) is emerging as a therapeutic approach to prevent, delay, or ameliorate frailty. In particular short session HIIT, ...