This work was supported by STW (12864, C.C.W.G.B) and the Netherlands Organization for Scientific Research (Rubicon Grant 825.12.016, T.M.H.E).

The steps described in the following section are in line with and accepted by the medical ethical committee of the Radboud University Medical Center in Nijmegen, The Netherlands. To our knowledge, 3 different commercial systems of ingestible temperature pills are currently available for researchers. The user manual of the ingestible temperature pills is brand-specific (Table of Specific Materials), but all systems are suitable for measurements during exercise and under resting conditions.
1. Exclusion Criteria and Subject Instruction
<ol>
	<li>Ask subjects in written or verbal form for the exclusion criteria for using the telemetric temperature pill: 1) body weight below 36.5 kg, 2) obstructive gastro-intestinal disease, 3) history of gastrointestinal surgery, 4) an implanted medical device, and 5) a scheduled MRI scan during the experimental period.</li>
	<li>Write down the serial and calibration number of the temperature pill.</li>
	<li>Instruct the subjects how to use the temperature pill (see section 2).</li>
	<li>Give the pill to the subject together with a short instruction manual, which contains the information shown in section 2. If subjects receive the temperature pill well ahead of the experiment, remind the subject the day preceding the experiment to ingest the temperature pill.</li>
</ol>
2. Temperature Pill Instructions
<ol>
	<li>Instruct the subject to ingest the temperature pill at least 6 hr&#160;prior to the experiment, to avoid any interaction with fluid ingestion. Follow the subsequent steps to ingest the temperature pill correctly.</li>
	<li>Instruct the subject to remove the magnetic strip from the pill, to activate the battery and enable measuring.</li>
	<li>Instruct the subject to ingest the temperature pill preferably with a glass of water to enhance pill ingestion.</li>
	<li>Ask the subject to return the pill wrapping material to the research team, so they can check serial and calibration numbers prior to the start of the experiment.</li>
	<li>Instruct the subject that the temperature pill will leave the body through its natural way (faeces) and it can be flushed through the toilet.</li>
</ol>
3. Experimental Protocol I: Cross Sectional Mode
Note: In the cross sectional mode it is possible to measure up to 99 subjects simultaneously.
<ol>
	<li>Adjust the recorder to the desired settings for the cross sectional measurement prior to the measurement.
	<ol>
		<li>Turn on the recorder, connect the recorder with the computer with a transfer cable and push the &#8216;F2-PC Link&#8217; button to enable the recorder to connect with the computer.</li>
		<li>Open the Tc software on the computer, which can be used to define the right settings. Note: The software is supplied by the company with the order of the temperature pill and recorder.</li>
		<li>To adjust the settings, click on &#8216;Program&#8217; in the home screen of the software, and subsequently use the &#8216;open PC link&#8217; button to make a connection with the recorder and select the correct settings.
		<ol>
			<li>Select the cross sectional measurement mode by selecting &#8216;Sports mode ON&#8217;.</li>
			<li>Select the correct temperature measurement scale (Celsius or Fahrenheit). Use the &#8216;Write Config to Recorder&#8217; button to copy the settings to the recorder.</li>
			<li>Add the serial and calibration number of all individual subjects to the external recorder, which enables the option to switch users during the experiment. Push the &#8216;Sensor/Barcode Display&#8217; button in the software and add all the serial and calibration numbers. Push the &#8216;Write Sensors to Recorder&#8217; button to copy the data to the recorder.</li>
			<li>Check the battery of the recorder prior to the measurement, to avoid a discharged battery during the measurement and therefore missing data. Note: Normally, a battery state of 75% is sufficient to measure for &#62;10 hr.</li>
		</ol>
		</li>
	</ol>
	</li>
	<li>Once all preparations are completed and the predefined settings are checked, start the experiment. To do so, return to the home screen of the recorder and use the &#8216;F2-Sport&#8217; button to start data acquisition.</li>
	<li>When Player XX appears on the screen, push the &#8216;Read&#8217; button to measure Tgi. Use the &#8216;Read&#8217; button again for an extra measurement of Tgi.</li>
	<li>To switch users, push on the correct number on the recorder and subsequently measure the Tc by pushing the &#8216;Read&#8217; button.</li>
	<li>Stop the data collection by pushing the &#8216;Stop&#8217; button.</li>
	<li>When the measurement is finished, turn off the recorder in the correct way to prevent data loss. To do so, use the &#8216;Enter&#8217; button and &#8216;Exit&#8217; becomes visible on the home screen. Push the &#8216;F1-Exit&#8217; button and the recorder shows &#8216;turn of recorder&#8217;. Subsequently, use the power switch to turn off the recorder.</li>
	<li>Export and store the raw data from the external recorder to a computer (see section 5; data handling).</li>
</ol>
4. Experimental Protocol II: Continuous Mode
Note: The continuous mode enables to continuously measure and save the Tgi of an individual subject on a predefined constant time interval, for example every 20 sec. In the next section, the step sequence used to perform this type of measurement is described.
<ol>
	<li>Adjust the recorder to the right settings for the continuous measurement mode prior to the measurement (see section 3, steps 3.1.1-3.1.3).</li>
	<li>Select the continuous measurement mode by selecting &#8216;Sports mode OFF&#8217;.</li>
	<li>Select a measuring frequency by adjusting the &#8216;Read Interval&#8217; to the right constant time interval (hh:mm:ss), with a minimal sampling interval of 10 sec.</li>
	<li>Select the correct temperature measurement scale (Celsius or Fahrenheit). Use the &#8216;Write Config to Recorder&#8217; button to copy the settings to the recorder.</li>
	<li>Check the battery of the recorder prior to the measurement, to avoid a discharged battery during the measurement and therefore missing data. Note: Normally, a battery state of 75% is sufficient to perform a 24 hr&#160;measurement.</li>
	<li>Once all preparations are completed and the predefined settings are checked, start the experiment. Start data acquisition by pushing the &#8216;Run&#8217; button on the home screen of the recorder.</li>
	<li>Subsequently, attach the recorder in a waist bag close to the abdominal area of the subject (maximal 30-40 cm between the abdominal area and the recorder) to avoid measurement errors. 
	Note: After the start of the experiment, every predefined time interval a measurement of Tc will be taken. With the &#8216;Read&#8217; button extra sampling points can be added.</li>
	<li>Stop the Tc measurement by pushing the &#8216;Stop&#8217; button.</li>
	<li>Use the &#8216;F1-Exit&#8217; button to get the message &#8216;turn off unit&#8217; and then use the power switch to turn off the recorder.</li>
	<li>Export and store the raw data from the external recorder to a computer (see section 5; data extraction).</li>
</ol>
5. Data Extraction
<ol>
	<li>Connect the recorder to the computer to complete data export (section 3, step 3.1.1).</li>
	<li>Open the software and click the &#8216;Download&#8217; button in the home screen of the software.</li>
	<li>Enter a file name and push the &#8216;OK&#8217; button. Note: The data will now be stored as a .cvt file, which can be opened using spreadsheet software.</li>
	<li>Open the data file and visually check the collected data for missing data and outliers. Note: A large decrease or increase of the Tgi (&#8804;1 &#176;C) within a short time interval (&#177;1 min) is very unrealistic and may be caused by a disturbance of the radio signal. As a result, the unrealistic data point can be removed for further analysis.</li>
	<li>Interpolate the missing values by averaging the previous and next valid value. Note: Interpolation of the data is possible with a maximum of three missing values in a row.</li>
</ol>

<ol>
	<li>Hawley, J. A., Hargreaves, M., Joyner, M. J., Zierath, J. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Integrative+Biology+of+Exercise.">Integrative Biology of Exercise.</a> Cell. 159, 738-749 (2014).</li><li>American College of Sports Medicine. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=American+College+of+Sports+Medicine+position+stand.+Exercise+and+fluid+replacement.">American College of Sports Medicine position stand. Exercise and fluid replacement.</a> Med Sci Sports Exerc. 39, 377-390 (2007).</li><li>Cheuvront, S. N., Haymes, E. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Thermoregulation+and+marathon+running:+biological+and+environmental+influences.">Thermoregulation and marathon running: biological and environmental influences.</a> Sports Med. 31, 743-762 (2001).</li><li>Kenefick, R. W., Cheuvront, S. N., Sawka, M. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Thermoregulatory+function+during+the+marathon.">Thermoregulatory function during the marathon.</a> Sports Med. 37, 312-315 (2007).</li><li>Tatterson, A. J., Hahn, A. G., Martin, D. T., Febbraio, M. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+heat+stress+on+physiological+responses+and+exercise+performance+in+elite+cyclists.">Effects of heat stress on physiological responses and exercise performance in elite cyclists.</a> J Sci Med Sport. 3, 186-193 (2000).</li><li>Bouchama, A., Knochel, J. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Heat+stroke.">Heat stroke.</a> N Engl J Med. 346, (1978).</li><li>Galloway, S. D., Maughan, R. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+ambient+temperature+on+the+capacity+to+perform+prolonged+cycle+exercise+in+man.">Effects of ambient temperature on the capacity to perform prolonged cycle exercise in man.</a> Med Sci Sports Exerc. 29, 1240-1249 (1997).</li><li>Hargreaves, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Physiological+limits+to+exercise+performance+in+the+heat.">Physiological limits to exercise performance in the heat.</a> J Sci Med Sport. 11, 66-71 (2008).</li><li>Byrne, C., Lim, C. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+ingestible+telemetric+body+core+temperature+sensor:+a+review+of+validity+and+exercise+applications.">The ingestible telemetric body core temperature sensor: a review of validity and exercise applications.</a> Br J Sports Med. 41, 126-133 (2007).</li><li>Sawka, M. N., Wenger, C., Pandolf, K. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Human performance physiology and environmental medicine at terrestrial extremes. , 97-151 (1988).</li><li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Ergonomics &#8212; Evaluation of thermal strain by physiological measurements. , (2004).</li><li>Blatteis, C. M., Blatteis, C. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Physiology and pathophysiology of temperature regulation. , 273-279 (1998).</li><li>Bagley, J. 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=Validity+of+field+expedient+devices+to+assess+core+temperature+during+exercise+in+the+cold.">Validity of field expedient devices to assess core temperature during exercise in the cold.</a> Aviat Space Environ Med. 82, 1098-1103 (2011).</li><li>Livingstone, S. D., Grayson, J., Frim, J., Allen, C. L., Limmer, R. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+Cold-Exposure+on+Various+Sites+of+Core+Temperature-Measurements.">Effect of Cold-Exposure on Various Sites of Core Temperature-Measurements.</a> J Appl Physiol (1985). 54, 1025-1031 (1983).</li><li>Gant, N., Atkinson, G., Williams, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+validity+and+reliability+of+intestinal+temperature+during+intermittent+running.">The validity and reliability of intestinal temperature during intermittent running.</a> Med Sci Sports Exerc. 38, 1926-1931 (2006).</li><li>Sawka, M. N., 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=Physiologic+tolerance+to+uncompensable+heat:+intermittent+exercise,+field+vs+laboratory.">Physiologic tolerance to uncompensable heat: intermittent exercise, field vs laboratory.</a> Med Sci Sports Exerc. 33, 422-430 (2001).</li><li>Stevens, C. J., Dascombe, B., Boyko, A., Sculley, D., Callister, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ice+slurry+ingestion+during+cycling+improves+Olympic+distance+triathlon+performance+in+the+heat.">Ice slurry ingestion during cycling improves Olympic distance triathlon performance in the heat.</a> J Sports Sci. 31, 1271-1279 (2013).</li><li>Wolff, H. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+radio+pill.">The radio pill.</a> New Science. 12, 419-421 (1961).</li><li>Casa, D. J., 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=Validity+of+devices+that+assess+body+temperature+during+outdoor+exercise+in+the+heat.">Validity of devices that assess body temperature during outdoor exercise in the heat.</a> J Athl Train. 42, 333-342 (2007).</li><li>Kolka, M. A., Quigley, M. D., Blanchard, L. A., Toyota, D. A., Stephenson, L. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Validation+of+a+Temperature+Telemetry+System+during+Moderate+and+Strenuous+Exercise.">Validation of a Temperature Telemetry System during Moderate and Strenuous Exercise.</a> J Therm Biol. 18, 203-210 (1993).</li><li>Lee, S. M., Williams, W. J., Schneider, S. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Core temperature measurement during submaximal exercise: esophageal, rectal, and intestinal temperatures. , (2000).</li><li>Bland, J. M., Altman, D. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Statistical+methods+for+assessing+agreement+between+two+methods+of+clinical+measurement.">Statistical methods for assessing agreement between two methods of clinical measurement.</a> Lancet. 1, 307-310 (1986).</li><li>Lim, C. L., Byrne, C., Lee, J. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Human+thermoregulation+and+measurement+of+body+temperature+in+exercise+and+clinical+settings.">Human thermoregulation and measurement of body temperature in exercise and clinical settings.</a> Ann Acad Med Singapore. 37, 347-353 (2008).</li><li>Brengelmann, G. L., Shiraki, K., Yousef, M. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Man in a Stressful Environment: Thermal and Work Physiology. , 5-22 (1987).</li><li>American College of Sports Medicine. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=American+College+of+Sports+Medicine+position+stand.+Exertional+heat+illness+during+training+and+competition.">American College of Sports Medicine position stand. Exertional heat illness during training and competition.</a> Med Sci Sports Exerc. 39, 556-572 (2007).</li><li>Easton, C., Fudge, B. W., Pitsladis, Y. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rectal,+telemetry+pill+and+tympanic+membrane+thermometry+during+exercise+heat+stress.">Rectal, telemetry pill and tympanic membrane thermometry during exercise heat stress.</a> J Therm Biol. 32, 78-86 (2007).</li><li>Moran, D. S., Mendal, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Core+temperature+measurement:+methods+and+current+insights.">Core temperature measurement: methods and current insights.</a> Sports Med. 32, 879-885 (2002).</li><li>Ganio, M. S., 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=Validity+and+reliability+of+devices+that+assess+body+temperature+during+indoor+exercise+in+the+heat.">Validity and reliability of devices that assess body temperature during indoor exercise in the heat.</a> J Athl Train. 44, 124-135 (2009).</li><li>Kolka, M. A., Levine, L., Stephenson, L. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Use+of+an+ingestible+telemetry+sensor+to+measure+core+temperature+under+chemical+protective+clothing.">Use of an ingestible telemetry sensor to measure core temperature under chemical protective clothing.</a> J Therm Biol. 22, 343-349 (1997).</li><li>Brien, C., Hoyt, R. W., Buller, M. J., Castellani, J. W., Young, A. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Telemetry+pill+measurement+of+core+temperature+in+humans+during+active+heating+and+cooling.">Telemetry pill measurement of core temperature in humans during active heating and cooling.</a> Med Sci Sports Exerc. 30, 468-472 (1998).</li><li>Wilkinson, D. M., Carter, J. M., Richmond, V. L., Blacker, S. D., Rayson, M. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+effect+of+cool+water+ingestion+on+gastrointestinal+pill+temperature.">The effect of cool water ingestion on gastrointestinal pill temperature.</a> Med Sci Sports Exerc. 40, 523-528 (2008).</li><li>Sparling, P. B., Snow, T. K., Millardstafford, M. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Monitoring+Core+Temperature+during+Exercise+-+Ingestible+Sensor+Vs+Rectal+Thermistor.">Monitoring Core Temperature during Exercise - Ingestible Sensor Vs Rectal Thermistor.</a> Aviat Space Environ Med. 64, 760-763 (1993).</li><li>Roach, G. D. S. C., Darwent, D., Kannaway, D. J., Furguson, S. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lost+in+transit:+The+journey+of+ingestible+temperature+sensors+through+the+human+digestive+tract.">Lost in transit: The journey of ingestible temperature sensors through the human digestive tract.</a> Ergonomia. 32, 49-61 (2010).</li><li>McKenzie, J. E., Osgood, D. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Validation+of+a+new+telemetric+core+temperature+monitor.">Validation of a new telemetric core temperature monitor.</a> J Therm Biol. 29, 605-611 (2004).</li><li>Palit, S., Lunniss, P. J., Scott, S. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+physiology+of+human+defecation.">The physiology of human defecation.</a> Dig Dis Sci. 57, 1445-1464 (2012).</li><li>Chien, L. Y., Liou, Y. M., Chang, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Low+defaecation+frequency+in+Taiwanese+adolescents:+association+with+dietary+intake,+physical+activity+and+sedentary+behaviour.">Low defaecation frequency in Taiwanese adolescents: association with dietary intake, physical activity and sedentary behaviour.</a> J Paediatr Child Health. 47, 381-386 (2011).</li></ol>

No conflicts of interest declared.

The ingestible telemetric temperature pill has the ability to provide a continuous, valid and non-invasive measurement of the Tgi. Furthermore, an advantage of the temperature pill is the fact that once ingested, the subjects are unaware of the presence of the pill in the body or that the measurements are performed. Therefore, this method is easily applicable under resting conditions as well as during exercise, a minimal burden for study participants, and can therefore be used in field and laboratory settings. Another ad...

The oxidation of substrates during muscle contractions, necessary to perform exercise and physical activity, importantly impacts our thermoregulatory system as only 20% is used for muscle power1, whilst the majority of the energy is released as heat (80%)2,3. As a consequence, the elevated metabolic heat production during physical activity and exercise typically exceeds the heat dissipation capacity4,5, resulting in an increase in core body temperature (Tc). Accordingly, Tc rises above the hypothalamic set point, which is defined as hyperthermia6, and may even result in an attenuated exercise performance5,7,8 and/or the development of heat-related disorders4,6. For this reason it is important to accurately measure Tc during prolonged exercise and in particular in strenuous ambient conditions.
Literature describes that an ideal method to measure Tc should: 1) be easy applicable, 2) not be biased by environmental conditions, 3) have a high temporal resolution to rapidly monitor changes in Tc, and 4) have the capacity to detect small changes (&#916;0.1&#176;C) in core body temperature9,10. An overview of the different methods to measure the Tc was given by the International Organization of Standardization (ISO 9886)11. It was stated that the esophageal temperature at the level of the left atrium provides the closest agreement with central blood temperature, while this measure is able to rapidly detect (minor) changes in temperature12. Although esophageal temperature measurements are generally accepted as the gold standard to record Tc, its invasive nature limits the practical use of this method. Alternative measures to monitor Tc rely on temperature recordings of external tympanic membrane, mouth, or rectum12. These measurement sites are not optimal to measure the Tc, given their invasive character, methodological difficulties and/or the potential bias by environmental conditions9,12-14 (Table 1). This highlights the need to explore alternative strategies to monitor (changes in) Tc.
Previous studies have described the use of an ingestible telemetric temperature pill as an easily applicable, reliable and valid method to measure the Tgi, which is a representative estimation of Tc9,15. Another, important, advantage of the temperature pill is the suitability in field-based situations, which is of great importance since exercise-induced elevations in Tc are generally higher in field than in laboratory settings16. Currently, the temperature pill is able to measure the Tgi every 10 sec&#160;with an accuracy of &#177;0.1&#176;C, which makes this technique very suitable to measure the Tgi during an exercise event or an important match. Furthermore, in a study by Stevens et al.17 it is demonstrated that the telemetric temperature pill may also be used to monitor intragastric temperature. The ingestible temperature pill is first described in 196118, and further developed at the Johns Hopkins University (Baltimore, USA) in collaboration with the Applied Physics Laboratory of the NASA. The result is a 20 x 10 mm capsule with a telemetry system, micro battery and a quartz crystal temperature sensor. The crystal sensor vibrates at a frequency relative to the temperature of the surrounding substance. This temperature radio signal is transmitted through the body, which can be measured by an external recorder (Figure 1). Each temperature pill has a unique serial and calibration number, which can be used by the recorder to convert the radio signal and measure the corresponding Tgi.
A small magnetic strip is attached to the outside of the temperature pill, which deactivates the battery. When this magnetic strip is removed, the pill is activated immediately and starts measuring Tc (Figure 2). Casa and colleagues,19 used six different techniques (gastrointestinal, rectal, aural, temporal, axial and forehead) to measure Tc, with the rectal temperature set as the reference value. They demonstrated that the gastrointestinal measurement of Tc with the temperature pill is the only technique that shows good agreement with the reference Tc. Others investigated the relation between Tgi and rectal temperature and have shown a small but significant bias ranging from 0.07&#176;C to 0.20&#176;C 9,15,20,21. Although the direction and magnitude of the bias differed between studies, the Bland and Altman 95% limits of agreement were &#177;0.4&#176;C, which is acceptable9,22. Additionally, in a review by Byrne et al.9 the Tgi is compared with the rectal and esophageal temperature (gold standard) as a measure for the Tc. They demonstrate that the Tgi measured with the temperature pill is a valid measure for Tc based on the good agreement between intestinal and esophageal temperature. Furthermore, the 95% Bland and Altman limits of agreement were limited to &#177;0.4&#176;C 22, while no significant bias was found between the two measurements9,20,21. These results suggest that the Tgi is a valid measure for Tc.
Another important aspect of a good Tc/Tgi measurement technique is a high temporal resolution to rapidly monitor changes in Tc. Previous studies have demonstrated that the Tgi measured with the temperature pill responds more slowly on changes in Tc compared to the esophageal measurement15,20,23, which can be explained due to the low heat capacity of the esophagus and the proximity to the heart10. In the esophageal temperature measurement, the thermistor is placed at the level of the left atrium10. At this level, the pulmonary artery and the esophagus are in contact and isothermal24, which stimulates a fast response time on changes in temperature of the esophageal measurement. In contrast, the intestines and rectum are less perfused compared to the esophagus, resulting in a delay in measuring temperature changes at these anatomical locations. However, the ingestible telemetric temperature pill has an accuracy of &#177;0.1&#176;C and is able to measure Tgi every 10 sec. A previous study reported that core body temperature can rise at a maximum of 1&#176;C every 5 min if no heat is removed during exercise25. Therefore, the temporal resolution of the temperature pill is suitable to measure changes in Tgi during exercise. Based on these findings, it can be concluded that the temperature pill is a reliable and valid technique to measure Tgi. Despite the use of the telemetric temperature pill in a large number of studies, a clear description about how to use the temperature pill is missing.
Therefore, the purpose of this study is to provide a detailed description of the measurement protocol using an ingestible telemetric temperature pill. Secondly, the application of the telemetric temperature pill in two different study protocols are described, in which a cross-sectional design (measurement every 5 km with a different recorder) and a protocol that continuously records Tgi in individuals are used.

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr>
			<td>CorTemp data recorder</td>
			<td>CorTemp system, HQ Inc., Florida, USA</td>
			<td>Not applicable</td>
			<td>http://www.hqinc.net/cortemp-data-recorder/</td>
		</tr>
		<tr>
			<td>Cortemp ingestible telemetric temperature pill</td>
			<td>CorTemp system, HQ Inc., Florida, USA</td>
			<td>HT150002</td>
			<td>http://www.hqinc.net/cortemp-sensor-2/</td>
		</tr>
		<tr>
			<td>CorTrack II software (Data processing for a PC only)</td>
			<td>CorTemp system, HQ Inc., Florida, USA</td>
			<td>Not applicable</td>
			<td>http://www.hqinc.net/cortrack-ii-data-graphing-software/</td>
		</tr>
	</tbody>
</table>

using an ingestible telemetric temperature pill to assess gastrointestinal temperature during exercise

Exercise results in an increase in core body temperature (Tc), which may reduce exercise performance and eventually can lead to the development of heat-related disorders. Therefore, accurate measurement of Tc during exercise is of great importance, especially in athletes who have to perform in challenging ambient conditions. In the current literature a number of methods have been described to measure the Tc (esophageal, external tympanic membrane, mouth or rectum). However, these methods are suboptimal to measure Tc during exercise since they are invasive, have a slow response or are influenced by environmental conditions. Studies described the use of an ingestible telemetric temperature pill as a reliable and valid method to assess gastrointestinal temperature (Tgi), which is a representative measurement of Tc. Therefore, the goal of this study was to provide a detailed description of the measurement of Tgi using an ingestible telemetric temperature pill. This study addresses important methodological factors that must be taken into account for an accurate measurement. It is recommended to read the instructions carefully in order to ensure that the ingestible telemetric temperature pill is a reliable method to assess Tgi at rest and during exercise.

Representative results from our previous work demonstrating the methods are presented in the next section, in which an example of a cross sectional (Figure 3A) and a continuous measurement (Figure 3B) are given.
Cross sectional measurement of Tgi
An example of data from a cross sectional measurement is shown in Figure 3A. After obtaining baseline Tgi, subjects walked 30 km at a self-selected pace. During exercise th...

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Using an Ingestible Telemetric Temperature Pill to Assess Gastrointestinal Temperature During Exercise

This study describes an accurate, reliable and non-invasive technique to continuously measure gastrointestinal temperature during exercise. The ingestible telemetric temperature pill is suitable to measure gastrointestinal temperature in laboratory settings as well as in field based settings.

Exercise results in an increase in core body temperature (Tc), which may reduce exercise performance and eventually can lead to the development of ...

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Unit 1

Vital Signs: Temperature

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10.4K vues.  Radboud University Medical Center. This study describes an accurate, reliable and non-invasive technique to continuously measure gastrointestinal temperature during exercise. The ingestible telemetric temperature pill is suitable to measure gastrointestinal temperature in laboratory settings as well as in field based settings. 

Vidéo: Using an Ingestible Telemetric Temperature Pill to Assess Gastrointestinal Temperature During Exercise

Using Learning Outcome Measures to assess Doctoral Nursing Education

Education programs at all levels must be able to demonstrate successful program outcomes. Grades alone do not represent a comprehensive measurement methodology for assessing student learning outcomes at either the course or program level. The development and application of assessment rubrics provides an unequivocal measurement methodology to ensure a quality learning experience by providing a foundation for improvement based on qualitative and quantitatively measurable, aggregate course and program outcomes.  Learning outcomes are the embodiment of the total learning experience and should incorporate assessment of both qualitative and quantitative program outcomes. The assessment of qualitative measures represents a challenge for educators in any level of a learning program. Nursing provides a unique challenge and opportunity as it is the application of science through the art of caring. Quantification of desired student learning outcomes may be enhanced through the development of assessment rubrics designed to measure quantitative and qualitative aspects of the nursing education and learning process. They provide a mechanism for uniform assessment by nursing faculty of concepts and constructs that are otherwise difficult to describe and measure. A protocol is presented and applied to a doctoral nursing education program with recommendations for application and transformation of the assessment rubric to other education programs. Through application of these specially designed rubrics, all aspects of an education program can be adequately assessed to provide information for program assessment that facilitates the closure of the gap between desired and actual student learning outcomes for any desired educational competency.

The structure and process for measuring student learning outcomes through customizable assessment rubrics is discussed and applied to a doctoral nursing education program.

Education programs at all levels must be able to demonstrate successful program outcomes. Grades alone do not represent a comprehensive measurement ...

Using Quantitative Real-time PCR to Determine Donor Cell Engraftment in a Competitive Murine Bone Marrow Transplantation Model

Murine bone marrow transplantation models provide an important tool in measuring hematopoietic stem cell (HSC) functions and determining genes/molecules that regulate HSCs. In these transplant model systems, the function of HSCs is determined by the ability of these cells to engraft and reconstitute lethally irradiated recipient mice. Commonly, the donor cell contribution/engraftment is measured by antibodies to donor- specific cell surface proteins using flow cytometry. However, this method heavily depends on the specificity and the ability of the cell surface marker to differentiate donor-derived cells from recipient-originated cells, which may not be available for all mouse strains. Considering the various backgrounds of genetically modified mouse strains in the market, this cell surface/ flow cytometry-based method has significant limitations especially in mouse strains that lack well-defined surface markers to separate donor cells from congenic recipient cells. Here, we reported a PCR-based technique to determine donor cell engraftment/contribution in transplant recipient mice. We transplanted male donor bone marrow HSCs to lethally irradiated congenic female mice. Peripheral blood samples were collected at different time points post transplantation. Bone marrow samples were obtained at the end of the experiments. Genomic DNA was isolated and the Y chromosome specific gene, Zfy1, was amplified using quantitative Real time PCR. The engraftment of male donor-derived cells in the female recipient mice was calculated against standard curve with known percentage of male vs. female DNAs. Bcl2 was used as a reference gene to normalize the total DNA amount. Our data suggested that this approach reliably determines donor cell engraftment and provides a useful, yet simple method in measuring hematopoietic cell reconstitution in murine bone marrow transplantation models. Our method can be routinely performed in most laboratories because no costly equipment such as flow cytometry is required.

Determining donor cell engraftment presents a challenge in mouse bone marrow transplant models that lack well-defined phenotypical markers. We described a methodology to quantify male donor cell engraftment in female transplant recipient mice. This method can be used in all mouse strains for the study of HSC functions.

Murine bone marrow transplantation models provide an important tool in measuring hematopoietic stem cell (HSC) functions and determining genes/molecules ...

Using Continuous Data Tracking Technology to Study Exercise Adherence in Pulmonary Rehabilitation

Pulmonary rehabilitation (PR) is an important component in the management of respiratory diseases. The effectiveness of PR is dependent upon adherence to exercise training recommendations. The study of exercise adherence is thus a key step towards the optimization of PR programs. To date, mostly indirect measures, such as rates of participation, completion, and attendance, have been used to determine adherence to PR. The purpose of the present protocol is to describe how continuous data tracking technology can be used to measure adherence to a prescribed aerobic training intensity on a second-by-second basis.
In our investigations, adherence has been defined as the percent time spent within a specified target heart rate range. As such, using a combination of hardware and software, heart rate is measured, tracked, and recorded during cycling second-by-second for each participant, for each exercise session. Using statistical software, the data is subsequently extracted and analyzed. The same protocol can be applied to determine adherence to other measures of exercise intensity, such as time spent at a specified wattage, level, or speed on the cycle ergometer. Furthermore, the hardware and software is also available to measure adherence to other modes of training, such as the treadmill, elliptical, stepper, and arm ergometer. The present protocol, therefore, has a vast applicability to directly measure adherence to aerobic exercise.

Pulmonary rehabilitation is widely recognized in the management of respiratory diseases. A key component to successful pulmonary rehabilitation is adherence to the recommended exercise training. The purpose of the present protocol is to describe how continuous data tracking technology can be used to precisely measure adherence to a prescribed aerobic training intensity.

Pulmonary rehabilitation (PR) is an important component in the management of respiratory diseases. The effectiveness of PR is dependent upon adherence to ...

Ex Vivo Intestinal Sacs to Assess Mucosal Permeability in Models of Gastrointestinal Disease

The epithelial barrier is the first innate defense of the gastrointestinal tract and selectively regulates transport from the lumen to the underlying tissue compartments, restricting the transport of smaller molecules across the epithelium and almost completely prohibiting epithelial macromolecular transport. This selectivity is determined by the mucous gel layer, which limits the transport of lipophilic molecules and both the apical receptors and tight junctional protein complexes of the epithelium. In vitro cell culture models of the epithelium are convenient, but as a model, they lack the complexity of interactions between the microbiota, mucous-gel, epithelium and immune system. On the other hand, in vivo assessment of intestinal absorption or permeability may be performed, but these assays measure overall gastrointestinal absorption, with no indication of site specificity. Ex vivo permeability assays using &#34;intestinal sacs&#34; are a rapid and sensitive method of measuring either overall intestinal integrity or comparative transport of a specific molecule, with the added advantage of intestinal site specificity. Here we describe the preparation of intestinal sacs for permeability studies and the calculation of the apparent permeability (Papp) of a molecule across the intestinal barrier. This technique may be used as a method of assessing drug absorption, or to examine regional epithelial barrier dysfunction in animal models of gastrointestinal disease.

Ex Vivo Intestinal Sacs to Assess Mucosal Permeability in Models of Gastrointestinal Disease

This protocol describes the use of excised intestinal tissue preparations or "intestinal sacs" as an ex vivo model of intestinal barrier function. This model may be used to assess integrity of both the epithelial barrier and the mucous gel layer at specific intestinal sites in animal models of digestive disease.

The epithelial barrier is the first innate defense of the gastrointestinal tract and selectively regulates transport from the lumen to the underlying ...

Assessment of Pulmonary Capillary Blood Volume, Membrane Diffusing Capacity, and Intrapulmonary Arteriovenous Anastomoses During Exercise

Exercise is a stress to the pulmonary vasculature. With incremental exercise, the pulmonary diffusing capacity (DLCO) must increase to meet the increased oxygen demand; otherwise, a diffusion limitation may occur. The increase in DLCO with exercise is due to increased capillary blood volume (Vc) and membrane diffusing capacity (Dm). Vc and Dm increase secondary to the recruitment and distension of pulmonary capillaries, increasing the surface area for gas exchange and decreasing pulmonary vascular resistance, thereby attenuating the increase in pulmonary arterial pressure. At the same time, the recruitment of intrapulmonary arteriovenous anastomoses (IPAVA) during exercise may contribute to gas exchange impairment and/or prevent large increases in pulmonary artery pressure.
We describe two techniques to evaluate pulmonary diffusion and circulation at rest and during exercise. The first technique uses multiple-fraction of inspired oxygen (FIO2) DLCO breath holds to determine Vc and Dm at rest and during exercise. Additionally, echocardiography with intravenous agitated saline contrast is used to assess IPAVAs recruitment.
Representative data showed that the DLCO, Vc, and Dm increased with exercise intensity. Echocardiographic data showed no IPAVA recruitment at rest, while contrast bubbles were seen in the left ventricle with exercise, suggesting exercise-induced IPAVA recruitment.
The evaluation of pulmonary capillary blood volume, membrane diffusing capacity, and IPAVA recruitment using echocardiographic methods is useful to characterize the ability of the lung vasculature to adapt to the stress of exercise in health as well as in diseased groups, such as those with pulmonary arterial hypertension and chronic obstructive pulmonary disease.

To assess the pulmonary diffusion and vasculature responses to exercise, we describe the multiple-inspired oxygen diffusion capacity technique to determine capillary blood volume and membrane diffusing capacity, as well as agitated saline contrast echocardiography to assess the recruitment of intrapulmonary arteriovenous anastomoses.

Exercise is a stress to the pulmonary vasculature. With incremental exercise, the pulmonary diffusing capacity (DLCO) must increase to meet the increased ...

Esophageal Heat Transfer for Patient Temperature Control and Targeted Temperature Management

Controlling patient temperature is important for a wide variety of clinical conditions. Cooling to normal or below normal body temperature is often performed for neuroprotection after ischemic insult (e.g. hemorrhagic stroke, subarachnoid hemorrhage, cardiac arrest, or other hypoxic injury). Cooling from febrile states treats fever and reduces the negative effects of hyperthermia on injured neurons. Patients are warmed in the operating room to prevent inadvertent perioperative hypothermia, which is known to cause increased blood loss, wound infections, and myocardial injury, while also prolonging recovery time. There are many reported approaches for temperature management, including improvised methods that repurpose standard supplies (e.g., ice, chilled saline, fans, blankets) but more sophisticated technologies designed for temperature management are typically more successful in delivering an optimized protocol. Over the last decade, advanced technologies have developed around two heat transfer methods: surface devices (water blankets, forced-air warmers) or intravascular devices (sterile catheters requiring vascular placement). Recently, a novel device became available that is placed in the esophagus, analogous to a standard orogastric tube, that provides efficient heat transfer through the patient&#39;s core. The device connects to existing heat exchange units to allow automatic patient temperature management via a servo mechanism, using patient temperature from standard temperature sensors (rectal, Foley, or other core temperature sensors) as the input variable. This approach eliminates vascular placement complications (deep venous thrombosis, central line associated bloodstream infection), reduces obstruction to patient access, and causes less shivering when compared to surface approaches. Published data have also shown a high degree of accuracy and maintenance of target temperature using the esophageal approach to temperature management. Therefore, the purpose of this method is to provide a low-risk alternative method for controlling patient temperature in critical care settings.

This study presents a novel method to provide efficient patient temperature control for cooling or warming patients. A single use, triple lumen device is placed into the esophagus, analogous to a standard orogastric tube, and connects to existing heat exchange units to perform automatic patient temperature management.

Controlling patient temperature is important for a wide variety of clinical conditions. Cooling to normal or below normal body temperature is often ...

An Optimized Evans Blue Protocol to Assess Vascular Leak in the Mouse

Vascular leak, or plasma extravasation, has a number of causes, and may be a serious consequence or symptom of an inflammatory response. This study may ultimately lead to new knowledge concerning the causes of or new ways to inhibit or treat plasma extravasation. It is important that researchers have the proper tools, including the best methods available, for studying plasma extravasation. In this article, we describe a protocol, using the Evans blue dye method, for assessing plasma extravasation in the organs of FVBN mice. This protocol is intentionally simple, to as great a degree as possible, but provides high quality data. Evans blue dye has been chosen primarily because it is easy for the average laboratory to use. We have used this protocol to provide evidence and support for the hypothesis that the enzyme neprilysin may protect the vasculature against plasma extravasation. However, this protocol may be experimentally used and easily adapted for use in other strains of mice or in other species, in many different organs or tissues, for studies which may involve other factors that are important in understanding, preventing, or treating plasma extravasation. This protocol has been extensively optimized and modified from existing protocols, and combines reliability, ease of use, economy, and general availability of materials and equipment, making this protocol superior for the average laboratory to use in quantifying plasma extravasation from organs.

In this article, an economical, optimized, and simple protocol is described which uses the Evans blue dye method for assessing plasma extravasation in the organs of FVBN mice that can be adapted for use in other strains, species, and other organs or tissues.

Vascular leak, or plasma extravasation, has a number of causes, and may be a serious consequence or symptom of an inflammatory response. This study may ...

Conducting Maximal and Submaximal Endurance Exercise Testing to Measure Physiological and Biological Responses to Acute Exercise in Humans

Regular physical activity has a positive effect on human health, but the mechanisms controlling these effects remain unclear. The physiologic and biologic responses to acute exercise are predominantly influenced by the duration and intensity of the exercise regimen. As exercise is increasingly thought of as a therapeutic treatment and/or diagnostic tool, it is important that standardizable methodologies be utilized to understand the variability and to increase the reproducibility of exercise outputs and measurements of responses to such regimens. To that end, we describe two different cycling exercise regimens that yield different physiologic outputs. In a maximal exercise test, exercise intensity is continually increased with a greater workload resulting in an increasing cardiopulmonary and metabolic response (heart rate, stroke volume, ventilation, oxygen consumption and carbon dioxide production). In contrast, during endurance exercise tests, the demand is increased from that at rest, but is raised to a fixed submaximal exercise intensity resulting in a cardiopulmonary and metabolic response that typically plateaus. Along with the protocols, we provide suggestions on measuring physiologic outputs that include, but are not limited to, heart rate, slow and forced vital capacity, gas exchange metrics, and blood pressure to enable the comparison of exercise outputs between studies. Biospecimens can then be sampled to assess cellular, protein, and/or gene expression responses. Overall, this approach can be easily adapted into both short- and long-term effects of two distinct exercise regimens.

To assess the influence of exercise intensity on physiologic and biologic responses, two different exercise testing protocols were utilized. Methods outlining exercise testing on a cycle ergometer as an incremental maximal oxygen consumption test and endurance, steady state submaximal endurance test are described.

Regular physical activity has a positive effect on human health, but the mechanisms controlling these effects remain unclear. The physiologic and biologic ...

Providing Visual Biofeedback Using Brightness Mode Ultrasound During a Golf Swing

Using ultrasound biofeedback in conjunction with verbal cueing can increase muscle thickness more than verbal cueing alone and may augment traditional rehabilitation techniques in an athletic, physically active population. Brightness mode (B-mode) ultrasound can be applied using frame-by-frame analysis synchronized with video to understand muscle thickness changes during these dynamic tasks. Visual biofeedback with ultrasound has been established in static positions for the muscles of the lateral abdominal wall. However, by securing the transducer to the abdomen using an elastic belt and foam block, biofeedback can be applied during more specific tasks prevalent in lifetime sports, such as golf. To analyze muscle activity during a golf swing, muscle thickness changes can be compared. The thickness must increase throughout the task, indicating that the muscle is more active. This methodology allows clinicians to immediately replay ultrasound videos for patients as a visual tool to instruct proper activity of the muscles of interest. For example, ultrasound can be used to target the external and internal obliques, which play an important role in swinging a golf club or any other rotational sport or activity. This methodology aims to increase oblique muscle thickness during the golf swing. Additionally, the timing of muscle contraction can be targeted by instructing the patient to contract the abdominal muscles at specific time points, such as the beginning of the downswing, with the goal of improving muscle firing patterns during tasks.

Brightness mode ultrasound can be used to provide visual biofeedback of the muscles of the lateral abdominal wall during a golf swing. Post-swing visual and verbal instruction can increase the muscle activation and timing of the external and internal obliques.

Using ultrasound biofeedback in conjunction with verbal cueing can increase muscle thickness more than verbal cueing alone and may augment traditional ...

Muscle Function Obtained with Motion Mode Ultrasound and Surface Electromyography during Core Endurance Exercise

Motion mode (M-mode) ultrasound allows researchers and clinicians to measure the change of muscle thickness across time. Muscle thickness can be measured between fascial borders at a given time point during an exercise. This selected time point produces a one-dimensional image resulting in real-time, live observation of anatomy. Ultrasound used during functional movement can be referred to as dynamic ultrasound; this is feasible and reliable with the use of a linear transducer, elastic belt, and foam block to secure consistent transducer placement. The lateral abdominal wall is commonly investigated using ultrasound due to the overlapping nature of the muscles. Surface electromyography (sEMG) can complement M-mode ultrasound imaging because it measures the electrical representation of muscle activation. There is minimal evidence using M-mode ultrasound and sEMG simultaneously during core exercise. Exercises that challenge the core musculature involve both isometric holds (e.g., side plank), as well as oscillatory extremity movements (e.g., dead bug). In this study, both instruments will be used simultaneously to measure core muscle function during exercise. Ultrasound measurements will be obtained using a linear transducer and ultrasound unit, and sEMG measurements will be acquired from a wireless sEMG system. To make comparisons between participants and exercises, normalization methods using static, exercise starting positions for both instruments will be used. An activation ratio will be used for ultrasound and calculated by dividing the contracted thickness (thickness during a time point of exercise) by the rested (starting position) thickness. Muscle thickness will be measured in centimeters from the superior inferior fascial border to inferior superior fascial border. These methods aim to offer an innovative and practical measurement of muscle function with M-mode ultrasound and sEMG during core endurance exercises.

This protocol uses motion mode ultrasound and surface electromyography simultaneously to measure muscle function of the core. Muscle thickness and activation of the local stabilizers (e.g., transverse abdominis, internal oblique) and global movers (e.g., external oblique) is achievable during specific time points of the side plank and dead bug exercises.

Motion mode (M-mode) ultrasound allows researchers and clinicians to measure the change of muscle thickness across time. Muscle thickness can be measured ...