This work was supported by the National Natural Science Foundation of China (Grant No. 31771319).

The protocol (No. 31771319) was approved by the Hebei Normal University Review Board and conformed to the Declaration of Helsinki. All participants provided written informed consent before participating in the testing described.
1. Participant Screening and Preparation for the Experiment
<ol>
	<li>For recruitment, ensure that the participants satisfy the following inclusion criteria: aged between 18 and 25, a minimum body mass index (BMI) of 23 kg/m, which is the overweight cut-off for Asian adults10, consistent body weight (&#177; 2 kg) for the most recent three months, no exercise training or regular physical activities, no record of hormonal, orthopaedic or cardiovascular diseases, diabetes, hyperlipidaemia, hypertension or polycystic ovary syndrome, as well as, no current use of prescribed medications (including contraceptive pills) and no history of smoking.</li>
	<li>Randomly assign 47 eligible participants to one of the following four groups: traditional HIE (n = 12), sprint interval exercise (SIE, n = 11), repeated sprint exercise (RSE, n = 12) or MCE (n = 12) group.</li>
	<li>Adjust and record the appropriate seat height on the cycling ergometers so that the participant pedals with a slight knee bend (~10&#176;) at full downstroke of the pedal.</li>
	<li>Instruct the participants to perform two initial exercise sessions (as described in step 3) to familiarize them with the respective type of cycling exercise (HIE, SIE, RSE or MCE).</li>
</ol>
2. Experimental Procedures
<ol>
	<li>First, instruct each participant to perform a continuous incremental test on a stress testing cycle ergometer to assess maximal oxygen uptake (V&#775;O2max).
	<ol>
		<li>Warm up for 5 min at 25 W. Then start the test by performing continuous 2 min stages (20 W increment per stage) starting at 50 W with a pedal frequency of 60 rpm until volitional exhaustion.</li>
		<li>Use a breath-by-breath metabolic analyzer to measure the oxygen consumption during the exercise.</li>
		<li>Calculate the V&#775;O2max based on the highest 30 s average value. Then, calculate a power output that elicits 60%, 90% and 120% V&#775;O2max in the MCE, HIE and SIE groups, respectively, using the equation of linear regression through plotting the steady state V&#775;O2 versus power output11.</li>
	</ol>
	</li>
	<li>At least 5 days after pre-intervention assessments, instruct the HIE, SIE, RSE and MCE groups to commence their respective training. 
	NOTE: Start all exercise tests at the same time of the day (e.g., 11:00 A.M.). Meanwhile, ensure that the tests are conducted in a laboratory with temperature and humidity-controlled settings (20 &#176;C and 50% relative humidity). Ask all participants to stick to both their daily activities and eating habits throughout the experiment.
	<ol>
		<li>Instruct the participant to refrain from any strenuous exercise for 48 h, after a routine warm-up, instruct the HIE, SIE, RSE and MCE groups to engage in their respective exercise session on a cycle ergometer as arranged. Perform the exercise protocol as detailed in step 3.</li>
		<li>Perform 6 exercise sessions carried out over a time span of 10 days for all four groups. Select the 1st (1ST) and 6th (6TH) exercise sessions to observe the cTnT response to the acute exercise (Figure 1).</li>
	</ol>
	</li>
</ol>
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/60252/60252fig01.jpg" /> 
Figure 1: Schematic diagram of study procedures.&#160;HIE = high-intensity interval exercise; SIE = sprint interval exercise; RSE = repeated sprint exercise; MCE = moderate-intensity continuous exercise. <a href="https://www.jove.com/files/ftp_upload/60252/60252fig01large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<ol start="4">
	<li>Record a continuous electrocardiogram (ECG) during exercise via a portable electrocardiograph (ECG) monitor.</li>
	<li>Draw venous blood samples before and immediately after exercise, as well as 3 h and 4 h after the selected exercise session to assess the serum cTnT. With the subjects in a seated position, draw 5 mL of venous blood from the antecubital vein for each sample. 
	NOTE: Post-exercise blood samples timings conformed to our prior work, which demonstrated that blood cTnT concentrations reached their peak 3 or 4 h following acute exercise in a laboratory-based study12.</li>
	<li>For the separation of the serum, allow the blood to clot at room temperature. Centrifuge the blood samples at 3,500 x g for 20 min.</li>
	<li>Aspirate the serum and store at -80 &#176;C for the subsequent analysis of cTnT.</li>
	<li>Use an analyzer to perform the quantitative measurement of the cTnT with a high sensitivity immunoassay based on electrochemiluminescence technology. Take 1 mL of the serum and put it into a special test tube for measuring cTnT. Then insert the tube in the analyzer and press the start button. 
	NOTE: The human cTnT protein itself consists of 288 amino acids. Two monoclonal antibodies are used for the assay which are specifically directed against human cardiac troponin T. The antibodies recognize the central part of cardiac troponin T protein4, specifically targeting two epitopes at amino acid positions 125-131 and 136-147.</li>
</ol>
3. Exercise Protocols
<ol>
	<li>In each exercise session, instruct the 4 groups to follow the steps below.
	<ol>
		<li>Complete an identical 10 min warm-up at 50-60% of HRmax (percentage of individual maximal heart rate during exercise session) and 5 min cool down at 20 W.</li>
		<li>Following the warm-up. Have a 2 min recovery period, where participants remain seated but stationary on the cycle ergometer.</li>
		<li>Direct the participants to accelerate as soon as possible at the beginning of each exercise bout to reach the intended intensity. During this time a researcher sets the respective exercise protocol in a PC computer and then counts down, &#34;5-4-3-2-1-Go!&#34;. At the command of &#34;Go!&#34;, participants start to exercise and activate the computerized system. 
		NOTE: For the MCE, HIE and SIE, accelerate to the planned intensity (see step 2.1.3), i.e. 60%, 90% and 120% V&#775;O2max, respectively. For the RSE, accelerate to &#8220;all-out&#8221; exercise (see step 3.4). The ergometer is linked to a PC computer with specific software.</li>
		<li>Instruct the participants to remain seated while cycling and secure their feet to the pedals using toe clips, and verbally encourage the participants to give a maximal effort to exercise at the desired intensity throughout each session.</li>
	</ol>
	</li>
	<li>HIE protocol: Repeat 4 min bouts of exercise on a stress testing cycle ergometer at an intensity of 90% V&#775;O2max, followed by a 3 min passive recovery (complete rest) until the targeted 200 kJ of work is achieved.</li>
	<li>SIE protocol: Repeat 1 min bouts of exercise on a stress testing cycle ergometer at an intensity of 120% of V&#775;O2max, followed by a 1.5 min passive recovery until the targeted 200 kJ of work is achieved.</li>
	<li>RSE protocol: Repeat 6 s &#8220;all-out&#8221; sprints interspersed with 9 s passive recovery periods on a Wingate testing cycle ergometer, with a resistance of 1.0 kg until the targeted 40 repetitions are achieved, and the total mechanical work was recorded.</li>
	<li>MCE protocol: Perform continuous cycling exercise, until a target of 200 kJ of work is achieved, at an intensity of 60% V&#775;O2max.</li>
</ol>
4. Statistical Analyses
<ol>
	<li>Perform data analysis using a statistical software package. Evaluate the normality of the data using the Kolmogorov&#8211;Smirnov test12. Use P &#60; 0.05 for assessing statistical significance.</li>
	<li>Compare the differences in HRmean (mean heart rate during exercise session) and %HRmax across the four groups (HIE, SIE, RSE and MCE) and the two observed exercise sessions (1ST and 6TH) using two-way ANOVA, with repeated measures. Use the Newman&#8211;Keuls post-hoc test for cases in which the main effect is significant.</li>
	<li>Compare cTnT across the time points (pre-exercise and peak post-exercise) and two observed exercise sessions (1ST and 6TH) using the non-parametric Wilcoxon signed ranks test because of the skewed distribution of the cTnT data. Further, the Kruskal-Wallis test was used to assess the statistical significance of differences in cTnT levels across the four groups (HIE, SIE, RSE and MCE), and the Mann-Whitney U test was used for pairwise comparisons where appropriate.</li>
</ol>

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	<li>Blair, S. N., Morris, J. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Healthy+hearts--and+the+universal+benefits+of+being+physically+active:+physical+activity+and+health.">Healthy hearts--and the universal benefits of being physically active: physical activity and health.</a> Annals of Epidemiology. 19 (4), 253-256 (2009).</li><li>Siscovick, D. S., Weiss, N. S., Fletcher, R. H., Lasky, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+incidence+of+primary+cardiac+arrest+during+vigorous+exercise.">The incidence of primary cardiac arrest during vigorous exercise.</a> The New England Journal of Medicine. 311 (14), 874-877 (1984).</li><li>Albert, C. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Triggering+of+sudden+death+from+cardiac+causes+by+vigorous+exertion.">Triggering of sudden death from cardiac causes by vigorous exertion.</a> The New England Journal of Medicine. 343 (19), 1355-1361 (2000).</li><li>Thygesen, K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fourth+universal+definition+of+myocardial+infarction+(2018).">Fourth universal definition of myocardial infarction (2018).</a> European Heart Journal. 40 (3), 237-269 (2019).</li><li>Gresslien, T., Agewall, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Troponin+and+exercise.">Troponin and exercise.</a> International Journal of Cardiology. 221, 609-621 (2016).</li><li>MacInnis, M. J., Gibala, M. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Physiological+adaptations+to+interval+training+and+the+role+of+exercise+intensity.">Physiological adaptations to interval training and the role of exercise intensity.</a> The Journal of Physiology. 595 (9), 2915-2930 (2017).</li><li>Poon, E. T., Sheridan, S., Chung, A. P., Wong, S. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Age+specific+affective+responses+and+self-efficacy+to+acute+high-intensity+interval+training+and+continuous+exercise+in+insufficiently+active+young+and+middle-aged+men.">Age specific affective responses and self-efficacy to acute high-intensity interval training and continuous exercise in insufficiently active young and middle-aged men.</a> Journal of Exercise Science and Fitness. 16 (3), 106-111 (2018).</li><li>Gaesser, G. A., Angadi, S. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High-intensity+interval+training+for+health+and+fitness:+can+less+be+more.">High-intensity interval training for health and fitness: can less be more.</a> Journal of Applied Physiology(1985). 111 (6), 1540-1541 (2011).</li><li>Mehta, R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Post-exercise+cardiac+troponin+release+is+related+to+exercise+training+history.">Post-exercise cardiac troponin release is related to exercise training history.</a> International Journal of Sports Medicine. 33 (5), 333-337 (2012).</li><li>World Health Organization. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Asia-Pacific+perspective:+redefining+obesity+and+its+treatment.">The Asia-Pacific perspective: redefining obesity and its treatment.</a> World Health Organization. , (2000).</li><li>Medbo, J. I., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Anaerobic+capacity+determined+by+maximal+accumulated+O2+deficit.">Anaerobic capacity determined by maximal accumulated O2 deficit.</a> Journal of Applied Physiology. 64 (1), 50-60 (1985).</li><li>Tian, Y., Nie, J., Huang, C., George, K. 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The authors declare that they have no competing financial interests.

The repetitive short to long bouts of rather high-intensity exercise interspersed with recovery periods are involved in HIE, which is subdivided into traditional HIE (&#8220;near maximal&#8221; efforts) and SIE (&#8220;supramaximal&#8221; efforts), using a common classification scheme6. In addition, RSE is a particularly intense form of SIE, where the activity is &#8220;all-out&#8221; but only lasts for 3 to 7 s6. To the best of our knowledge, this is the first integrated s...

The benefits of regular exercise on the heart are well-documented1. However, the risk of cardiac events, such as acute myocardial infarction (AMI), transiently increases during an intense exercise2,3. Individuals with low levels of regular physical activity show higher risk towards AMI2,3. Cardiac troponin T (cTnT) is the biochemical gold standard in the diagnosis of AMI4. However, there is a burgeoning evidence that the cTnT is elevated after continuous prolonged exercise, which undoubtedly distorts the diagnostic role of the cTnT assay5.
The repetitive bouts of relatively intense exercise interspersed with short breaks are a typical element of high-intensity interval exercise (HIE), which is growing in popularity in various fields such as cardiac rehabilitation, health and fitness6,7. The widespread interest in HIE is due in part to the ability of HIE training to elicit beneficial physiological adaptations similar or superior to the traditional moderate-intensity continuous exercise (MCE) training, despite a reduced total exercise volume and time commitment6. However, concerns related to the safety of HIE have been expressed due to the high cardiac demand8. To date, available data related to cTnT release upon HIE is limited. Moreover, no previous integrated study has investigated the effect of various modalities of HIE and traditional MCE on the appearance of cTnT with exercise. Thus, it is unclear whether, with equalization of total mechanical work between HIE and MCE, different exercise formats will lead to the distinction in cTnT concentrations and what the range of the elevated cTnT values is. Given that exercise conducted at higher intensities might lead to a higher risk of cardiac events2,3, it is pertinent to develop a representative HIE and MCE proposals with the known range of cTnT responses. The evaluation of exercise-associated cTnT elevation could potentially be helpful in clinical decision-making and assist clinical physiologists in developing more effective and safe exercise prescriptions.
Consequently, we outline protocols of the three representative types of HIE and one representative type of MCE to gather physiological data while observing cTnT responses. Considering that the risk of acute cardiac events is higher in people who do not engage in regular exercise2,3 and the overall release of cTnT induced by exercise reduces with regular training9, this study recruited sedentary, overweight females who completed a 10 day training program. This provided the prospect to work in the early stage of training and target an under-researched group.

<table>
	<tbody>
		<tr>
			<td>Cobas E 601 analyser</td>
			<td>Roche Diagnostics, Penzberg, Germany</td>
			<td></td>
			<td>Used for measuring the circulating cardiac troponin T concentration</td>
		</tr>
		<tr>
			<td>Monark 839E Stress Testing Cycle Ergometer&#160;</td>
			<td>Monark Exercise AB, Vansbro, Sweden</td>
			<td></td>
			<td>Used for all exercise protocols except repeated sprint exercise</td>
		</tr>
		<tr>
			<td>Monark 894E Wingate Testing Cycle Ergometer&#160;</td>
			<td>Monark Exercise AB, Vansbro, Sweden</td>
			<td></td>
			<td>Only used for repeated sprint exercise protocol</td>
		</tr>
		<tr>
			<td>Quark-PFT-ergo Metabolic Analyser</td>
			<td>Cosmed, Rome, Italy</td>
			<td>C09072-02-99</td>
			<td></td>
		</tr>
		<tr>
			<td>SPSS Statistics 20.0 software package</td>
			<td>IBM Corp., Armonk, USA</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Zephyr BioHarness 3.0</td>
			<td>Zephyr Technology, Auckland, New Zealand</td>
			<td>9800.0189/9600.0190</td>
			<td>Electrocardiograph Monitor</td>
		</tr>
	</tbody>
</table>

impact of high-intensity interval exercise and moderate-intensity continuous exercise on the cardiac troponin t level at an early stage of training

An elevation in cardiac troponin T (cTnT), as a highly specific biomarker of cardiomyocyte damage, after moderate-intensity continuous exercise (MCE) has been described. The exercise-induced cTnT response distorts the diagnostic role of the cTnT assay. Although high-intensity interval exercise (HIE) is growing in popularity and concerns remain about its safety, available data related to cTnT release after HIE is limited, which hampers the use of HIE as a health intervention. Here, we present three representative HIE protocols [traditional HIE (repeated 4 min cycling at 90% V&#775;O2max interspersed with 3 min rest, 200 kJ/session); sprint interval exercise (SIE, repeated 1 min cycling at 120% V&#775;O2max interspersed with 1.5 min rest, 200 kJ/session); and repeated sprint exercise (RSE, 40 x 6 s all-out sprints interspersed with 9 s rest)] and one representative MCE protocol (continuous cycling exercise at an intensity of 60% V&#775;O2max, 200 kJ/session). Forty-seven sedentary, overweight young women were randomly assigned to one of four groups (HIE, SIE, RSE, and MCE). Six bouts of respective exercise were performed by every single group, with each being 48 h apart. Meanwhile, for four groups, the duration of the entire testing period was identical, being 10 days. Before and after the first and final exercise bouts, an assessment was conducted of cTnT. The current study provides a frame of reference giving a clear picture of how a specific exercise session affects the circulating cTnT concentration at the early stage of training. The information may assist with clinical interpretations of post-exercise cTnT elevation and guide the prescription of exercise, especially for HIE.

All participants (n = 47) completed the study, and no adverse cardiac events (e.g., chest pain and sign of myocardial ischemia on ECG) were found during testing in the four groups. As expected, the acute exercise heart rate (HR) data, including HRmean and %HRmax, at the 1ST assessment is similar (all P &#62; 0.05) to those in the 6TH assessment in all four groups. Further, the HR data in the RSE and MCE groups is the highest and lowest among the four groups, respectively, but is similar bet...

Watch this Scientific Journal Video about Impact of High-intensity Interval Exercise and Moderate-Intensity Continuous Exercise on the Cardiac Troponin T Level at an Early Stage of Training at JoVE.co

Impact of High-intensity Interval Exercise and Moderate-Intensity Continuous Exercise on the Cardiac Troponin T Level at an Early Stage of Training

Here, we present protocols of high-intensity interval and moderate-intensity continuous exercise to observe the response of circulating cardiac troponin T (cTnT) concentration to acute exercise over 10 days. The information may assist with clinical interpretations of post-exercise cTnT elevation and guide the prescription of exercise.

An elevation in cardiac troponin T (cTnT), as a highly specific biomarker of cardiomyocyte damage, after moderate-intensity continuous exercise (MCE) has ...

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7.2K Views.  Hebei Normal University. Here, we present protocols of high-intensity interval and moderate-intensity continuous exercise to observe the response of circulating cardiac troponin T (cTnT) concentration to acute exercise over 10 days. The information may assist with clinical interpretations of post-exercise cTnT elevation and guide the prescription of exercise.

Video: Impact of High-intensity Interval Exercise and Moderate-Intensity Continuous Exercise on the Cardiac Troponin T Level at an Early Stage of Training

Getting to Compliance in Forced Exercise in Rodents: A Critical Standard to Evaluate Exercise Impact in Aging-related Disorders and Disease

There is a major increase in the awareness of the positive impact of exercise on improving several disease states with neurobiological basis; these include improving cognitive function and physical performance. As a result, there is an increase in the number of animal studies employing exercise. It is argued that one intrinsic value of forced exercise is that the investigator has control over the factors that can influence the impact of exercise on behavioral outcomes, notably exercise frequency, duration, and intensity of the exercise regimen. However, compliance in forced exercise regimens may be an issue, particularly if potential confounds of employing foot-shock are to be avoided. It is also important to consider that since most cognitive and locomotor impairments strike in the aged individual, determining impact of exercise on these impairments should consider using aged rodents with a highest possible level of compliance to ensure minimal need for test subjects. Here, the pertinent steps and considerations necessary to achieve nearly 100% compliance to treadmill exercise in an aged rodent model will be presented and discussed. Notwithstanding the particular exercise regimen being employed by the investigator, our protocol should be of use to investigators that are particularly interested in the potential impact of forced exercise on aging-related impairments, including aging-related Parkinsonism and Parkinson&#8217;s disease.

Exercise may alleviate behavioral impairments associated with neurodegenerative diseases. Studies of the mechanisms underlying exercise-mediated effects have increased in disease models, but the neurobiological background accompanying these diseases, specifically aging, is likely not considered. Here, we illustrate measures to increase the likelihood of a successful exercise paradigm in aged rats.

There is a major increase in the awareness of the positive impact of exercise on improving several disease states with neurobiological basis; these ...

Assessment of Murine Exercise Endurance Without the Use of a Shock Grid: An Alternative to Forced Exercise

Using laboratory mouse models, the molecular pathways responsible for the metabolic benefits of endurance exercise are beginning to be defined. The most common method for assessing exercise endurance in mice utilizes forced running on a motorized treadmill equipped with a shock grid. Animals who quit running are pushed by the moving treadmill belt onto a grid that delivers an electric foot shock; to escape the negative stimulus, the mice return to running on the belt. However, avoidance behavior and psychological stress due to use of a shock apparatus can interfere with quantitation of running endurance, as well as confound measurements of postexercise serum hormone and cytokine levels. Here, we demonstrate and validate a refined method to measure running endurance in na&#239;ve C57BL/6 laboratory mice on a motorized treadmill without utilizing a shock grid. When mice are preacclimated to the treadmill, they run voluntarily with gait speeds specific to each mouse. Use of the shock grid is replaced by gentle encouragement by a human operator using a tongue depressor, coupled with sensitivity to the voluntary willingness to run on the part of the mouse. Clear endpoints for quantifying running time-to-exhaustion for each mouse are defined and reflected in behavioral signs of exhaustion such as splayed posture and labored breathing. This method is a humane refinement which also decreases the confounding effects of stress on experimental parameters.

A method to assess exercise endurance in laboratory mice without the use of a shock grid is demonstrated. This method is a humane refinement that can decrease the confounding effects of stress on experimental parameters.

Using laboratory mouse models, the molecular pathways responsible for the metabolic benefits of endurance exercise are beginning to be defined. The most ...

Multifunctional Setup for Studying Human Motor Control Using Transcranial Magnetic Stimulation, Electromyography, Motion Capture, and Virtual Reality

The study of neuromuscular control of movement in humans is accomplished with numerous technologies. Non-invasive methods for investigating neuromuscular function include transcranial magnetic stimulation, electromyography, and three-dimensional motion capture. The advent of readily available and cost-effective virtual reality solutions has expanded the capabilities of researchers in recreating &#8220;real-world&#8221; environments and movements in a laboratory setting. Naturalistic movement analysis will not only garner a greater understanding of motor control in healthy individuals, but also permit the design of experiments and rehabilitation strategies that target specific motor impairments (e.g. stroke). The combined use of these tools will lead to increasingly deeper understanding of neural mechanisms of motor control. A key requirement when combining these data acquisition systems is fine temporal correspondence between the various data streams. This protocol describes a multifunctional system&#8217;s overall connectivity, intersystem signaling, and the temporal synchronization of recorded data. Synchronization of the component systems is primarily accomplished through the use of a customizable circuit, readily made with off the shelf components and minimal electronics assembly skills.

Transcranial magnetic stimulation, electromyography, and 3D motion capture are commonly used non-invasive techniques for investigating neuromuscular function in humans. In this paper, we describe a protocol that synchronously samples data generated by all three of these tools along with the unique addition of virtual reality stimulus presentation and feedback.

The study of neuromuscular control of movement in humans is accomplished with numerous technologies. Non-invasive methods for investigating neuromuscular ...

A Method for Evaluating the Reinforcing Properties of Ethanol in Rats without Water Deprivation, Saccharin Fading or Extended Access Training

Operant oral self-administration methods are commonly used to study the reinforcing properties of ethanol in animals. However, the standard methods require saccharin/sucrose fading, water deprivation and/or extended training to initiate operant responding in rats. This paper describes a novel and efficient method to quickly initiate operant responding for ethanol that is convenient for experimenters and does not require water deprivation or saccharin/sucrose fading, thus eliminating the potential confound of using sweeteners in ethanol operant self-administration studies. With this method, Wistar rats typically acquire and maintain self-administration of a 20% ethanol solution in less than two weeks of training. Furthermore, blood ethanol concentrations and rewards are positively correlated for a 30 min self-administration session. Moreover, naltrexone, an FDA-approved medication for alcohol dependence that has been shown to suppress ethanol self-administration in rodents, dose-dependently decreases alcohol intake and motivation to consume alcohol for rats self-administering 20% ethanol, thus validating the use of this new method to study the reinforcing properties of alcohol in rats.

This protocol describes a novel and efficient method to quickly initiate operant responding for ethanol in rats that, contrary to standard methods, does not require water deprivation or saccharin/sucrose fading to initiate responding.

Operant oral self-administration methods are commonly used to study the reinforcing properties of ethanol in animals. However, the standard methods ...

Behavioral Assessment of Hearing in 2 to 4 Year-old Children: A Two-interval, Observer-based Procedure Using Conditioned Play-based Responses

Collecting reliable behavioral data from toddlers and preschoolers is challenging. As a result, there are significant gaps in our understanding of human auditory development for these age groups. This paper describes an observer-based procedure for measuring hearing sensitivity with a two-interval, two-alternative forced-choice paradigm. Young children are trained to perform a play-based, motor response (e.g., putting a block in a bucket) whenever they hear a target signal. An experimenter observes the child&#39;s behavior and makes a judgment about whether the signal was presented during the first or second observation interval; the experimenter is blinded to the true signal interval, so this judgment is based solely on the child&#39;s behavior. These procedures were used to test 2 to 4 year-olds (n = 33) with no known hearing problems. The signal was a 1,000 Hz warble tone presented in quiet, and the signal level was adjusted to estimate a threshold corresponding to 71%-correct detection. A valid threshold was obtained for 82% of children. These results indicate that the two-interval procedure is both feasible and reliable for use with toddlers and preschoolers. The two-interval, observer-based procedure described in this paper is a powerful tool for evaluating hearing in young children because it guards against response bias on the part of the experimenter.

This paper describes a procedure for measuring hearing sensitivity in 2 to 4 year-old children. Children are trained to perform play-based responses when they hear a target signal. Thresholds are then estimated in a two-interval, two-alternative forced-choice paradigm, based on observations of the child&#39;s behaviors.

Collecting reliable behavioral data from toddlers and preschoolers is challenging. As a result, there are significant gaps in our understanding of human ...

An Objective and Child-friendly Assessment of Arm Function by Using a 3-D Sensor

Progressive and irreversible muscle atrophy characterizes Spinal Muscular Atrophy (SMA) and other similar muscle disorder diseases. Objective assessment of muscle functions is an essential and important, although challenging, prerequisite for successful clinical trials. Current clinical rating scales restrain the movement abnormalities to certain predefined coarse-grained individual items. The Kinect 3-D sensor has emerged as a low-cost and portable motion sensing technology used to capture and track people&#39;s movement in many medical and research fields. A novel approach using this 3-D sensor was developed and a game-like test was designed to objectively measure the upper limb function of patients with SMA. The prototype test targeted joint movement capability. While sitting in a virtual scene, the patient was instructed to extend, flex, and lift the whole arm in order to reach and place some objects. Both kinematic and spatiotemporal characteristics of upper limb movement were extracted and analyzed, e.g., elbow extension and flexion angles, hand velocity, and acceleration. The first study included a small cohort of 18 ambulant SMA patients and 19 age- and gender-matched healthy controls. A comprehensive analysis of arm movement was achieved; however, no significant difference between the groups were found due to the mismatch of patient&#39;s capability and the test difficulty. Based on this experience, a second version of the test consisting of a modified version of the first game with increased difficulties and a second game targeting muscle endurance were designed and implemented. The new test has not been conducted in any patient groups yet. Our work has demonstrated the potential capability of the 3-D sensor in assessing such muscle function and suggested an objective approach to complement the clinical rating scales.

An objective measure of muscle functions is challenging especially in children. Based on a commercially available digital 3-D sensor, a child-friendly gaming test was developed to assess upper limb function for clinical trials.

Progressive and irreversible muscle atrophy characterizes Spinal Muscular Atrophy (SMA) and other similar muscle disorder diseases. Objective assessment ...

Continuous Noninvasive Measuring of Crayfish Cardiac and Behavioral Activities

A crayfish is a pivotal aquatic organism that serves both as a practical biological model for behavioral and physiological studies of invertebrates and as a useful biological indicator of water quality. Even though crayfish cannot directly specify the substances that cause water quality deterioration, they can immediately (within a few seconds) warn humans of water quality deterioration via acute changes in their cardiac and behavioral activities.
In this study, we present a noninvasive method that is simple enough to be implemented under various conditions due to a combination of simplicity and reliability in one model.
This approach, in which the biological organisms are implemented into environmental evaluation processes, provides a reliable and timely alarm for warning of and preventing acute water deterioration in an ambient environment. Therefore, this noninvasive system based on crayfish physiological and ethological parameter recordings was investigated for the detection of changes in an aquatic environment. This system is now applied at a local brewery for controlling&#160;quality of the water used for beverage production, but it can be used at any water treatment and supply facility for continuous, real-time water quality evaluation and for regular laboratory investigations of crayfish cardiac physiology and behavior.

This article presents a noninvasive biomonitoring system for the continuous recording and analyses of crayfish cardiac and locomotor activities. This system consists of a near-infrared optical sensor, a video-tracking module, and software for evaluating crayfish heartbeats that reflects its physiological condition and characterizes crayfish behavior during heartbeat fluctuations.

A crayfish is a pivotal aquatic organism that serves both as a practical biological model for behavioral and physiological studies of invertebrates and as ...

Supramaximal Intensity Hypoxic Exercise and Vascular Function Assessment in Mice

Exercise training is an important strategy for maintaining health and preventing many chronic diseases. It is the first line of treatment recommended by international guidelines for patients suffering from cardiovascular diseases, more specifically, lower extremity artery diseases, where the patients' walking capacity is considerably altered, affecting their quality of life. 
Traditionally, both low continuous exercise and interval training have been used. Recently, supramaximal training has also been shown to improve athletes' performances via vascular adaptations, amongst other mechanisms. The combination of this type of training with hypoxia could bring an additional and/or synergic effect, which could be of interest for certain pathologies. Here, we describe how to perform supramaximal intensity training sessions in hypoxia on healthy mice at 150% of their maximal speed, using a motorized treadmill and a hypoxic box. We also show how to dissect the mouse in order to retrieve organs of interest, particularly the pulmonary artery, the abdominal aorta, and the iliac artery. Finally, we show how to perform ex vivo vascular function assessment on the retrieved vessels, using isometric tension studies.

High-intensity training in hypoxia is a protocol that has been proven to induce vascular adaptations potentially beneficial in some patients and to improve athletes&#39; repeated sprint ability. Here, we test the feasibility of training mice using that protocol and identify those vascular adaptations using ex vivo vascular function assessment.

Exercise training is an important strategy for maintaining health and preventing many chronic diseases. It is the first line of treatment recommended by ...

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, ...

Home-Based Prescribed Pulmonary Exercise in Patients with Stable Chronic Obstructive Pulmonary Disease

As a systemic disease, chronic obstructive pulmonary disease (COPD) affects the respiratory system, inducing restless and exercise dyspnea. It also impacts exercise capacity and forms a vicious circle in which it further aggravates the condition of patients and accelerates disease progression. As a functional holistic exercise, traditional Chinese exercises (TCE) play an important role in the rehabilitation of COPD on the basis of adjusting the breath and performing coordinated movements. This study investigates the effects of prescribed pulmonary exercises (which are modified from TCE) on exercise capacity of upper and lower limbs, endurance exercise capacity, and quality of life in stable COPD patients. The goal is to determine the accessibility of these prescribed exercises in COPD rehabilitation. Participants are randomly divided into a non-exercise control group (CG) or prescribed pulmonary exercise group (PG) at a ratio of 1: 1. The PG receives intervention for 60 min twice per day, 7 days a week, for a total of 3 months. The intensity is measured using the Borg category-ratio 10 scale and with a heart-rate monitor. Then, an exercise capacity test and quality of life questionnaire are scheduled at 1 week before and after the formal intervention. After 3 months of intervention, the 30 s arm curl test, 30 s sit-to-stand test, 6 min walking test, and quality of life show significant improvement in COPD patients (p &#60; 0.05). These findings indicate that prescribed pulmonary exercises can be applied as alternative, convenient, and effective home- and community-based exercises for stable COPD patients.

Presented here is a protocol to investigate the effects of home-based prescribed pulmonary exercise in stable chronic obstructive pulmonary disease (COPD) patients, which is modified based on traditional Chinese exercises according to dyspnea and limited exercise capacity observed in COPD patients.

As a systemic disease, chronic obstructive pulmonary disease (COPD) affects the respiratory system, inducing restless and exercise dyspnea. It also ...