This work was supported by Natural Science Foundation of Beijing (No.7162124), and Xin-ao Foundation for Beijing University of Chinese Medicine.

All the animals were maintained in accordance with the guidelines by the Chinese legislation on the ethical use and care of laboratory animals.
1. Pre-modeling Preparation
<ol>
	<li>Laboratory preparation
	<ol>
		<li>Run the UV lamp for at least 30 min before the experiment.</li>
		<li>Control the lab temperature at 25 &#177; 3 &#176;C, and relative humidity around 30%.</li>
		<li>Turn on the lab light at 6:00 and turn it off at 18:00 to establish a 12 h/12 h light/dark cycle.</li>
	</ol>
	</li>
	<li>Multiple Platform box construction
	<ol>
		<li>Construct an opaque plastic tank without a cover of 110 &#215; 60 &#215; 40 cm3.</li>
		<li>Fix fifteen circular platforms (h = 8 cm, d = 6.5 cm) on the bottom of the tank, which orderly distribute in three rows and five columns. Leave enough space between each platform, roughly 10 cm between columns and 13 cm between rows.</li>
		<li>Set a water outlet on the lateral side of the tank and install a faucet.</li>
		<li>Make an iron-wire netting cover for the tank with a food box hanging on it.</li>
	</ol>
	</li>
	<li>Grouping and housing rats 
	NOTE: Wistar male rats of 8 weeks old, weighing approximately 200 - 210 g, are used in the experiment. The rats live in groups during the modeling process.
	<ol>
		<li>Number the rats&#39; tail roots with a marker pen.</li>
		<li>Weigh the rats, exclude the extremely light or heavy ones, and divide the rest randomly into the model and control groups.</li>
		<li>Put the rats gently into the clean cages and allow them to acclimate to the lab for at least 3 days. Provide sufficient water and food supply.</li>
	</ol>
	</li>
</ol>
2. Modeling with MMPM
NOTE: The process starts at 18:00 and ends at 8:00 the next day, for a total of 14 h per day, over 21 days. To avoid interference factors, the same person is required to conduct the entire experiment, while wearing the same lab coat. 10 Wistar rats are used in the experiment.
<ol>
	<li>Place the tank on a flat surface, e.g., the floor. Then fill the tank with roughly 7 cm of warm (25 &#177; 3 &#176;C) water, approximately 1 cm below the platform flat.</li>
	<li>Prepare enough food and drink for all the rats in the tank for 1 day. Put fodder and water into the food box and hang it on the cover. 
	NOTE: Some smart rats learn to rest on the food box. If so, drive them back into the tank.</li>
	<li>Take the model group rats out of the cage, grab them by the tail, and put them gently into the tank. Launch all the rats in the water instead of the platforms to motivate their fear of water. Make sure that every rat gets a platform to stand on, while rats of the control group stay in their original cages with sufficient food and water.</li>
	<li>Cover the tank. Monitor the rats to avoid accidental injury. If a rat stays in water for more than 1 h without climbing onto the platform, pick it out of the tank and remove it from the test.</li>
	<li>After 14 h, take the model rats out of the tank and dry their hair with a dryer. Re-mark the rats&#39; tails if it fades. Return the rats to their original cages and provide them with sufficient food and water.</li>
	<li>Flush every corner of the tank. Elevate one side of the tank and open the faucet to outflow the sewage.</li>
	<li>Sterilize the tank with a 75% ethanol spray and expose it to the UV light.</li>
</ol>
3. Model Assessment: Behavioral Test
NOTE: All the tests are performed in the behavioral lab. Noise and extra light are not allowed during the test to avoid disturbance. If possible, use the same person(s) to conduct each test. A dark coat and gloves are required for grey scale recognition in image processing. Perform the OFT first as it has the least effect on rat behavior.
<ol>
	<li>OFT
	<ol>
		<li>Check the recorder over the Open Field Box to make sure it is properly connected to the workstation and covers every corner of the box. Adjust the lighting to eliminate shadows in the box.</li>
		<li>Move the rats into the behavioral lab in their original cages. Allow them to acclimate for at least 1 h before the test.</li>
		<li>Clean and sanitize the box with 75% ethanol to ensure that there is no excrement or smell left from previous experiment.</li>
		<li>Remove a rat from the cage by its back and put it gently into the central area of the box. Quickly retreat arms from the box so as not to block the shot.</li>
		<li>Input the rat&#39;s number and start recording. Count and record the frequency of the rat&#39;s vertical activities, including rearing and climbing.</li>
		<li>After 5 min, stop recording, take the rat out of the box, and return it to the cage.</li>
		<li>Repeat steps 3.1.3 -&#160;3.1.6 until all the rats have finished the test.</li>
	</ol>
	</li>
	<li>EPM
	<ol>
		<li>Perform the pre-check and acclimation steps as for the OFT (steps 3.1.1 - 3.1.2).</li>
		<li>Remove a rat from the cage by its back and put it gently onto the junction part of the two arms. Land the rat towards the left open arm and leave quickly so as not to block the shot.</li>
		<li>Input the rat&#39;s number and start recording. Count and record the frequency of different arm entrances. If the rat drops off the maze in the test, pick it up and send it back to the maze. Record detailed information for data analysis.</li>
		<li>After 5 min, stop recording, take the rat out, and return it to the cage.</li>
		<li>Remove the excrement and wipe the maze with 75% ethanol to eliminate the former rat&#39;s smell.</li>
		<li>Repeat steps 3.2.2 - 3.2.5 until all the rats have finished the test.</li>
	</ol>
	</li>
	<li>ES test
	<ol>
		<li>Fill the swimming tank (70 &#215; 30 &#215; 110 cm3) with 80 cm of warm (25 &#177; 3 &#176;C) water. 
		NOTE: If there is a thermostat in the tank, the water temperature should be set around 37 &#176;C, which is similar to the rat&#39;s body temperature. If not, set it to room temperature to keep it constant.</li>
		<li>Make a load for each rat with pin bunches and tie it gently on its tail root. The load weighs 10% of the rat&#39;s weight.</li>
		<li>Grab a rat by the tail and throw it into the swimming tank. If the rats huddle or cling to the wall, set them apart and drive them back into water.</li>
		<li>Start timing at the moment when the rat is put into water and stop timing when it&#39;s exhausted, which is demonstrated as the failure to struggle out of water with the mouth and nose beneath the water for more than 10 s. 
		NOTE: Sometimes, exhaustion and drowning occur suddenly. Be sure to have enough experimenters to record and save the&#160;animal at the same time.</li>
		<li>Remove the exhausted rats out of the water without interrupting others. Dry their hair, re-mark their numbers, and send them back to cage.</li>
		<li>Change the water in the tank after one group finishes. After all the rats are done, empty the swimming tank, and&#160;clean and sterilize it with ethanol and UV light.</li>
	</ol>
	</li>
</ol>
4. Model Assessment: Central Neurotransmitter Detection
<ol>
	<li>Anesthetize the rat with intra-peritoneal injection of 10% chloral hydrate (3 mL/kg) until it is unconscious.</li>
	<li>Decapitate the rat.</li>
	<li>Make a longitudinal incision along the post-medial line, open the cranium to both sides, and expose the brain. Turn the cranium over, remove the brain, and put the brain on an ice bag.</li>
	<li>Separate and remove the hypothalamus, which is the diamond-shaped area in the central part of the base of the brain that has a clear boundary with surrounding tissues. Place it in a sterile tube and freeze it with liquid nitrogen. Store all the samples in a -80 &#176;C refrigerator.</li>
	<li>Detect the content of DA and 5-HT in the hypothalamus using high-performance liquid chromatography (HPLC)8.</li>
</ol>

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The authors have nothing to disclose.

The MMPM is originally designed for sleep deprivation9. Rats are launched into a water tank with platforms fixed on the bottom. Driven by the instinctive fear of water, rats remain standing on the platforms and no sleep occurs. The study shows that different hours of sleep deprivation lead to various changes in rat behavior and mood, including recognition impairment10, negative emotions11, and central fatigue. Some researchers prove that chronic slee...

Fatigue is one of the main factors that threaten human health1. In the past decades, various researches have proved that fatigue is peripherally-triggered but centrally-driven, and always accompanied with emotional and cognitive disorders. Italian physiologist A. Mosso first proposed the word Central Fatigue2. It is generally defined as limited voluntary activity and cognition impairment due to dysfunction of impulse transmission in the central nervous system (CNS)3. Compared with peripheral muscle fatigue, central fatigue emphasizes changes in the CNS, as well as the consequent emotional/behavioral disturbances, including depression, anxiety, cognition impairment, and memory loss. One study shows that many factors can induce central fatigue, among which excessive physical activity and mental stress are quite indispensable4. As for the pathogenesis, theories like the tryptophan-kynurenine pathway hypothesis5 explain changes in certain pathways; however, more in-depth studies are still required&#160;to reveal the central-peripheral correlations of central fatigue.
As the underlying mechanism of central fatigue is still unclear, an effective animal model is quite important for further research. The existing fatigue models are mostly induced by excessive exercise, like treadmills6 and weight-loaded swimming7, with little concern on mental factors. To better simulate the development of central fatigue, our group developed a rat model with the MMPM. During the modeling process, rats remain standing on the narrow platforms in the Multiple Platform box for long hours including part of the sleep time. Different from excessive exercise models, the MMPM model uses partial sleep deprivation as a mental factor in consideration of the complex pathogenesis of central fatigue.
For model evaluation, we use the OFT and EPM tests to determine anxiety mood and voluntary activity. The ES test is performed to measure the peripheral muscle performance. In addition, we take the rat&#39;s brain and detect dopamine (DA)/serotonin (5-HT) content in both hypothalamuses to observe the central neurotransmitter differences.
The protocol presented below is designed to model central fatigue induced by repeated physical activity and lack of sleep, mimicking a common condition in human life. However, by adjusting the model duration, it can be used in many other fields, like in sleep observation and stress studies. In future research, we hope that this model will help discover more CNS changes and their connection with the peripheral system, to reveal the pathogenesis mechanism of central fatigue.

<table><tbody><tr><td>multiple platform sleep deprivation water tank</td><td>Customization,it is provided by the neuroimmunological laboratory of Beijing University of Chinese Medicine</td><td></td><td>110cm x 60cm x 40cm. There are 15 plastic small platforms at the bottom. The small platform is 6.5cm in diameter and 8cm high</td></tr><tr><td>Wistar rats</td><td>Beijing Weitong Lihua Experimental Animal Technology Company</td><td>license number SYXK (Beijing) 2016-0011</td><td>Use 32 Wistar healthy male rats ,8 week old (200-210 g)</td></tr><tr><td>Agilent 1100LC high performance liquid chromatograph&amp;nbsp;</td><td>Agilent</td><td>&amp;nbsp;G1379A, G1311A, G1313A , G1316A&amp;nbsp;</td><td>&amp;nbsp;G1379A, G1311A type chromatographic pump, G1313A automatic sampler, G1316A column temperature box</td></tr><tr><td>DECADE II SDC electrochemical detector</td><td>Dutch ANTEC company</td><td></td><td>glassy carbon electrode, Ag/AgCl reference electrode, workstations (Clarity CHS)</td></tr><tr><td>Biofuge Stratos high-speed refrigeration centrifuge</td><td>HERAEUS</td><td></td><td></td></tr><tr><td>VCX130 ultrasonic fracturing instrument</td><td>SONICS</td><td></td><td></td></tr><tr><td>ACS-ZEAS electronic scale</td><td>Phos technology development, Beijing.</td><td></td><td>The weight of the weighing rats can be accurate to 0.1g.</td></tr><tr><td>Open Field Box</td><td>Customization,it is provided by the neuroimmunological laboratory of Beijing University of Chinese Medicine</td><td></td><td>wooden box of open field&amp;nbsp; 100 cm by 100 cm x 40 cm, inside wall and bottom as the gray.The bottom is divided into 25 equal area squares, each of which is 20cm x 20cm, and the 16 grids along the outer wall are the external ones, and the other 9 grids are central.The camera is mounted above the median.</td></tr><tr><td>Elevated Plus-maze</td><td>Beijing zhongshi dechuang technology development co. LTD.</td><td></td><td>The open arms and close&amp;nbsp; arms of the cross are composed of 30cm x 5cm x 15cm, and the central area is 5cm x 5cm, with a camera mounted above the center and 45cm high.</td></tr><tr><td>rat swimming bucket.</td><td>Zhenhua biological instrument equipment co., LTD. Anhui,China.</td><td></td><td>The volume of plastic drum is 70cm x 30cm x 110cm, which is used for swimming in rats.</td></tr><tr><td>Thermometer</td><td>Shiya instrument co., LTD., changzhou,China.</td><td></td><td>Control water temperature</td></tr><tr><td>Small water pump</td><td>Xincheng technology co., LTD., chengdu,China.</td><td></td><td>Used for water tank and swimming behavior.</td></tr><tr><td>Ethovition3.0 behavioral software.</td><td>Nuldus,Netherlands</td><td></td><td>Measurement analysis of rat behavior videos.</td></tr></tbody></table>

a rat model of central fatigue using a modified multiple platform method

In this article, we introduced a rat model of central fatigue using the modified multiple platform method (MMPM). The Multiple Platform box was designed as a water tank with narrow platforms on the bottom. The model rats were put into the tank and stood on the platforms for 14 h (18:00 - 8:00) per day for a consecutive 21 days, with a blank control group set for contrast. At the end of modeling, rats in the model group showed an obvious fatigued appearance. To assess the model, we performed several behavioral tests, including the open field test (OFT), the elevated plus maze (EPM) test, and the exhaustive swimming (ES) test. The results showed that anxiety, spatial cognition impairment, poor muscle performance, and declined voluntary activity presented in model rats confirm the diagnosis of&#160;central fatigue. Changes of the central neurotransmitters also verified the result. In conclusion, the model successfully simulated central fatigue, and future study with the model may help reveal the pathological mechanism of the disease.

We describe a rat model of central fatigue using MMPM. 24 Wistar rats are randomly divided into the control group and the model group, with 12 rats in each group. The model apparatus is designed as a water tank with narrow platforms on the bottom (Figure 1). Model Rats stand on the platforms for 14 h per day, including partial sleep time, for 21 days (Figure 2).
Behavio...

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A Rat Model of Central Fatigue Using a Modified Multiple Platform Method

Here, we present a protocol to introduce a rat model of central fatigue using the modified multiple platform method (MMPM).

In this article, we introduced a rat model of central fatigue using the modified multiple platform method (MMPM). The Multiple Platform box was designed ...

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Research

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9.0K Views.  Beijing University of Chinese Medicine. Here, we present a protocol to introduce a rat model of central fatigue using the modified multiple platform method (MMPM).

Video: A Rat Model of Central Fatigue Using a Modified Multiple Platform Method

A Mouse Model of Fatigue Induced by Peripheral Irradiation

Cancer-related fatigue (CRF) is a distressing and costly condition that often affects patients receiving cancer treatments, including radiation therapy. Here we describe a method using targeted peripheral irradiation to induce fatigue-like behavior in mice. With appropriate shielding, the irradiation targets the lower abdominal/pelvic region of the mouse, sparing the brain, in an effort to model radiation treatment received by individuals with pelvic cancers. We deliver an irradiation dose that is sufficient to induce fatigue-like behavior in mice, measured by voluntary wheel-running activity (VWRA), without causing obvious morbidity. Since wheel running is a normal, voluntary behavior in mice, its use should have little confounding effect on other behavioral tests or biological measures. Hence, wheel running can be used as a feasible outcome measure in understanding the behavioral and biological correlates of fatigue. CRF is a complex condition with frequent comorbidities, and likely has causes related both to cancer and its various treatments. The methods described in this paper are useful for investigating radiation-induced changes that contribute to the development of CRF and, more generally, to explore the biological networks that can explain the development and persistence of a peripherally-triggered but centrally-driven behavior like fatigue.

We describe a method using targeted peripheral irradiation to induce fatigue-like behavior in mice. The selected non-lethal irradiation dose leads to a week-long reduction in voluntary wheel-running activity.

Cancer-related fatigue (CRF) is a distressing and costly condition that often affects patients receiving cancer treatments, including radiation therapy. ...

Cancer Research

Force and Position Control in Humans - The Role of Augmented Feedback

During motor behaviour, humans interact with the environment by for example manipulating objects and this is only possible because sensory feedback is constantly integrated into the central nervous system and these sensory inputs need to be weighted in order meet the task specific goals. Additional feedback presented as augmented feedback was shown to have an impact on motor control and motor learning. A number of studies investigated whether force or position feedback has an influence on motor control and neural activation. However, as in the previous studies the presentation of the force and position feedback was always identical, a recent study assessed whether not only the content but also the interpretation of the feedback has an influence on the time to fatigue of a sustained submaximal contraction and the (inhibitory) activity of the primary motor cortex using subthreshold transcranial magnetic stimulation. This paper describes one possible way to investigate the influence of the interpretation of feedback on motor behaviour by investigating the time to fatigue of submaximal sustained contractions together with the neuromuscular adaptations that can be investigated using surface EMG. Furthermore, the current protocol also describes how motor cortical (inhibitory) activity can be investigated using subthreshold TMS, a method known to act solely on the cortical level. The results show that when participants interpret the feedback as position feedback, they display a significantly shorter time to fatigue of a submaximal sustained contraction. Furthermore, subjects also displayed an increased inhibitory activity of the primary cortex when they believed to receive position feedback compared when they believed to receive force feedback. Accordingly, the results show that interpretation of feedback results in differences on a behavioural level (time to fatigue) that is also reflected in interpretation-specific differences in the amount of inhibitory M1 activity.

Controlling an identical movement with position or force feedback results in different neural activation and motor behavior. This protocol describes how to investigate behavioral changes by looking at neuromuscular fatigue and how to evaluate motor cortical (inhibitory) activity using subthreshold TMS with respect to the interpretation of augmented feedback.

During motor behaviour, humans interact with the environment by for example manipulating objects and this is only possible because sensory feedback is ...

Behavior

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 ...

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: ...

Measuring the Motor Aspect of Cancer-Related Fatigue using a Handheld Dynamometer

Cancer-related fatigue (CRF) is commonly reported by patients both during and after receiving treatment for cancer. Current CRF diagnoses rely on self-report questionnaires which are subject to report and recall biases. Objective measurements using a handheld dynamometer, or handgrip device, have been shown in recent studies to correlate significantly with subjective self-reported fatigue scores. However, variations of both the handgrip fatigue test and fatigue index calculations exist in the literature. The lack of standardized methods limits the utilization of the handgrip fatigue test in the clinical and research settings. In this study, we provide detailed methods for administering the physical fatigue test and calculating the fatigue index. These methods should supplement existing self-reported fatigue questionnaires and help clinicians assess fatigue symptom severity in an objective and quantitative manner.

Simple and accessible methods were developed to measure the motor aspect of cancer-related fatigue objectively and quantitatively. We describe, in detail, ways to administer the physical fatigue test using a simple handgrip device as well as methods to calculate fatigue indices.

Cancer-related fatigue (CRF) is commonly reported by patients both during and after receiving treatment for cancer. Current CRF diagnoses rely on ...

Revised and Neuroimaging-Compatible Versions of the Dual Task Screen

Dual task paradigms simultaneously assess motor and cognitive abilities, and they can detect subtle, residual impairments in athletes with recent mild traumatic brain injury (mTBI). However, past dual task paradigms have focused solely on lower extremity skills and have relied on cumbersome, expensive laboratory equipment - thus limiting their practicality for everyday mTBI evaluation. Subsequently, we developed the Dual Task Screen (DTS), which takes &#60;10 minutes to administer and score, uses low-cost portable equipment, and includes lower extremity (LE) and upper extremity (UE) subtasks. The purpose of this manuscript was twofold. First, we describe the administration protocol for the revised DTS, which we revised to address the limitations of the original DTS. Specifically, the revisions included additions of smart devices to acquire more detailed gait data and inclusion of single cognitive conditions to test for disrupted cognitive performance under dual task conditions. Importantly, the revised DTS is a measure intended for future clinical use, and we present representative results from three male athletes to illustrate the type of clinical data that can be acquired from the measure. Importantly, we have yet to evaluate the sensitivity and specificity of the revised DTS in athletes with mTBI, which is the next research initiative. The second purpose of this manuscript is to describe a neuroimaging-compatible version of the DTS. We developed this version so we could evaluate the neural underpinnings of single and dual task performance, for a better empirical understanding of the behavioral deficits associated with mTBI. Thus, this manuscript also describes the steps we took to enable simultaneous functional near-infrared spectroscopy (fNIRS) measurement during the DTS, along with how we acquired and completed first-level processing of the fNIRS data.

We developed the original Dual Task Screen (DTS) as a portable, low-cost measure that can evaluate athletes with sports-induced mild traumatic brain injury. We revised the original DTS for future clinical use and developed a neuroimaging-compatible version of the DTS to measure neural underpinnings of single and dual task performance.

Dual task paradigms simultaneously assess motor and cognitive abilities, and they can detect subtle, residual impairments in athletes with recent mild ...

Integrating VR and Biosensors for Quantitative Motion-Muscle Activity Assessment

Setup for the Quantitative Assessment of Motion and Muscle Activity During a Virtual Modified Box and Block Test

The ability to move allows us to interact with the world. When this ability is impaired, it can significantly reduce one's quality of life and independence and may lead to complications. The importance of remote patient evaluation and rehabilitation has recently grown due to limited access to in-person services. For example, the COVID-19 pandemic unexpectedly resulted in strict regulations, reducing access to non-emergent healthcare services. Additionally, remote care offers an opportunity to address healthcare disparities in rural, underserved, and low-income areas where access to services remains limited. 
Improving accessibility through remote care options would limit the number of hospital or specialist visits and render routine care more affordable. Finally, the use of readily available commercial consumer electronics for at-home care can enhance patient outcomes due to improved quantitative observation of symptoms, treatment efficacy, and therapy dosage. While remote care is a promising means to address these issues, there is a crucial need to quantitatively characterize motor impairment for such applications. The following protocol seeks to address this knowledge gap to enable clinicians and researchers to obtain high-resolution data on complex movement and underlying muscle activity. The ultimate goal is to develop a protocol for remote administration of functional clinical tests. 
Here, participants were instructed to perform a medically-inspired Box and Block task (BBT), which is frequently used to assess hand function. This task requires subjects to transport standardized cubes between two compartments separated by a barrier. We implemented a modified BBT in virtual reality to demonstrate the potential of developing remote assessment protocols. Muscle activation was captured for each subject using surface electromyography. This protocol allowed for the acquisition of high-quality data to better characterize movement impairment in a detailed and quantitative manner. Ultimately, these data have the potential to be used to develop protocols for virtual rehabilitation and remote patient monitoring.

Author Spotlight: Enhancing Remote Rehabilitation with Virtual Reality and Electromyography

The protocol described here aims to enhance the quantitative evaluation of upper limb deficits, with the goal of developing additional technology for remote assessment both in the clinic and at home. Virtual reality and biosensor technologies are combined with standard clinical techniques to provide insights into the functioning of the neuromuscular system.

The ability to move allows us to interact with the world. When this ability is impaired, it can significantly reduce one's quality of life and ...

Engineering

Determining The Electromyographic Fatigue Threshold Following a Single Visit Exercise Test

Theoretically, the electromyographic (EMG) fatigue threshold is the exercise intensity an individual can maintain indefinitely without the need to recruit more motor units which is associated with an increase in the EMG amplitude. Although different protocols have been used to estimate the EMG fatigue threshold they require multiple visits which are impractical for a clinical setting. Here, we present a protocol for estimating the EMG fatigue threshold for cycle ergometry which requires a single visit. This protocol is simple, convenient, and completed within 15-20 min, therefore, has the potential to be translated into a tool that clinicians can use in exercise prescription.

This protocol describes the electromyographic fatigue threshold which demarcates between nonfatiguing and fatiguing exercise workloads. This information could be used to develop a more individualized training program.

Theoretically, the electromyographic (EMG) fatigue threshold is the exercise intensity an individual can maintain indefinitely without the need to recruit ...

Medicine

Functional Isolation of Single Motor Units of Rat Medial Gastrocnemius Muscle

This work outlines functional isolation of motor units (MUs), a standard electrophysiological method for determining characteristics of motor units in hindlimb muscles (such as the medial gastrocnemius, soleus, or plantaris muscle) in experimental rats. A crucial element of the method is the application of electrical stimuli delivered to a motor axon isolated from the ventral root. The stimuli may be delivered at constant or variable inter-pulse intervals. This method is suitable for experiments on animals at varying stages of maturity (young, adult or old). Moreover, this protocol can be used in experiments studying variability and plasticity of motor units evoked by a large spectrum of interventions. The results of these experiments may both augment basic knowledge in muscle physiology and be translated into practical applications. This procedure focuses on the surgical preparation for the recording and stimulation of MUs, with an emphasis on the necessary steps to achieve preparation stability and reproducibility of results.

This method allows the recording of the force of twitch and tetanic contractions and action potentials in three types of motor units in the rat medial gastrocnemius muscle. The functional isolation of a single motor unit is induced by electrical stimulation of the axon.

This work outlines functional isolation of motor units (MUs), a standard electrophysiological method for determining characteristics of motor units in ...

Assessing the Impact of Anti-Fatigue Decoction on Rat Central Fatigue

The Effect of Anti-Fatigue Decoction on the Behaviors and Serological Indicators in a Central Fatigue Rat Model

This study aimed to assess the effects of Anti-fatigue Decoction (AFD) against central fatigue by observing the behaviors and serological indicators of rats modeled by the modified multiple platform method (MMPM) after drug intervention. Grip strength measurements were used to evaluate the muscle strength of rats. The open field test was utilized to assess anxiety-like behavior, while the Morris water maze test was conducted to evaluate the memory function of the rats. Following the behavioral assessments, rat serum samples were collected to measure the concentrations of corticosterone (CORT) and lactic acid (LAC). The concentration of LAC was determined using the colorimetric method, while the concentration of CORT was measured using the enzyme-linked immunosorbent assay (ELISA) method. Compared to the blank control group, following MMPM modeling, rats exhibited significant reductions in grip strength and impaired ability to memory. The serum analysis revealed increased levels of LAC and CORT in the model group rats. AFD can noticeably reverse these adverse changes to a certain extent. These findings highlight the positive effects of AFD and coenzymeQ10 on physical and cognitive abilities and alterations in serum biomarker levels of central fatigue rats.

Here, we introduce a protocol to assess the effects of anti-fatigue decoction (AFD) on central fatigue in rats modeled by the modified multiple platform method (MMPM) by monitoring both their behavioral responses and serological markers.

This study aimed to assess the effects of Anti-fatigue Decoction (AFD) against central fatigue by observing the behaviors and serological indicators of ...