Name: a real-world high-intensity interval training protocol for cardiorespiratory fitness improvement
Uploaded: 2022-02-22T14:00:00
Description: Watch this Scientific Journal Video about A Real-World High-Intensity Interval Training Protocol for Cardiorespiratory Fitness Improvement at JoVE.com

Thanks to the Centro Integrado de P&#243;s-Gradua&#231;&#227;o e Pesquisa em Sa&#250;de, (CIPq-Sa&#250;de) from the Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM) for providing equipment and technical support for experiments. Thanks to the Funda&#231;&#227;o de Amparo &#224; Pesquisa do Estado de Minas Gerais (FAPEMIG) (finance codes APQ-00214-21, APQ-00583-21, APQ-00938-18, APQ-03855-16, APQ-01728-18), Conselho Nacional de Desenvolvimento Cient&#237;fico e Tecnol&#243;gico (CNPq) (finance code 438498/2018-6), and Coordena&#231;&#227;o de Aperfei&#231;oamento de Pessoal de N&#237;vel Superior (CAPES) (Finance code 001) for providing financial support.

This study was approved by the Federal University of the Jequitinhonha and Mucuri Valleys Ethics and Research Committee. All participants were informed of the study objectives and experimental procedures of the study and signed a written informed consent form before their participation.
1. Experimental design
<ol>
	<li>Select individuals who meet the inclusion criteria: nonsmoking healthy individuals aged between 30 and 50 years with body mass index (BMI) of &#8805;25 kg&#18...

<ol>
	<li>Gibala, M. J., Little, J. P., Macdonald, M. J., Hawley, J. A. <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+low-volume,+high-intensity+interval+training+in+health+and+disease.">Physiological adaptations to low-volume, high-intensity interval training in health and disease.</a> The Journal of Physiology. 590 (5), 1077-1084 (2012).</li><li>Gist, N. H., Fedewa, M. V., Dishman, R. K., Cureton, K. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sprint+interval+training+on+aerobic+capacity:+a+systematic+review+and+meta-analysis.">Sprint interval training on aerobic capacity: a systematic review and meta-analysis.</a> Sports Medicine. 44 (2), 269-279 (2014).</li><li>Gillen, J. B., 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=Is+high-intensity+interval+training+a+time-efficient+exercise+strategy+to+improve+health+and+fitness.">Is high-intensity interval training a time-efficient exercise strategy to improve health and fitness.</a> Applied Physiology, Nutrition, and Metabolism. 39 (3), 409-412 (2014).</li><li>Fowles, J. R., O'Brien, M. W., Solmundson, K., Oh, P. I., Shields, C. 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S. <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+high-intensity+interval+training+on+cardiometabolic+health:+a+systematic+review+and+meta-analysis+of+intervention+studies.">Effects of high-intensity interval training on cardiometabolic health: a systematic review and meta-analysis of intervention studies.</a> British Journal of Sports Medicine. 51 (6), 494-503 (2017).</li><li>Gray, S. R., Ferguson, C., Birch, K., Forrest, L. J., Gill, J. M. <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:+key+data+needed+to+bridge+the+gap+from+laboratory+to+public+health+policy.">High-intensity interval training: key data needed to bridge the gap from laboratory to public health policy.</a> British Journal of Sports Medicine. 50 (20), 1231-1232 (2016).</li><li>Leger, L. A., Mercier, D., Gadoury, C., Lambert, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+multistage+20+metre+shuttle+run+test+for+aerobic+fitness.">The multistage 20 metre shuttle run test for aerobic fitness.</a> Journal of Sports Sciences. 6 (2), 93-101 (1988).</li><li>Olds, T., Tomkinson, G., L&#233;ger, L., Cazorla, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Worldwide+variation+in+the+performance+of+children+and+adolescents:+an+analysis+of+109+studies+of+the+20-m+shuttle+run+test+in+37+countries.">Worldwide variation in the performance of children and adolescents: an analysis of 109 studies of the 20-m shuttle run test in 37 countries.</a> Journal of Sports Sciences. 24 (10), 1025-1038 (2006).</li><li>Ainsworth, B. E., 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=Compendium+of+physical+activities:+a+second+update+of+codes+and+MET+values.">Compendium of physical activities: a second update of codes and MET values.</a> Medicine and Science in Sports and Exercise. 43 (8), 1575-1581 (2011).</li><li>Roy, 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=HIIT+in+the+real+world:+outcomes+from+a+12-month+intervention+in+overweight+adults.">HIIT in the real world: outcomes from a 12-month intervention in overweight adults.</a> Medicine and Science in Sports and Exercise. 50 (9), 1818-1826 (2018).</li><li>Medina-Mirapeix, F., Escolar-Reina, P., Gascon-Canovas, J. J., Montilla-Herrador, J., Collins, 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=Personal+characteristics+influencing+patients'+adherence+to+home+exercise+during+chronic+pain:+a+qualitative+study.">Personal characteristics influencing patients' adherence to home exercise during chronic pain: a qualitative study.</a> Journal of Rehabilitation Medicine. 41 (5), 347-352 (2009).</li><li>Medina-Mirapeix, F., 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=Predictive+factors+of+adherence+to+frequency+and+duration+components+in+home+exercise+programs+for+neck+and+low+back+pain:+an+observational+study.">Predictive factors of adherence to frequency and duration components in home exercise programs for neck and low back pain: an observational study.</a> BMC Musculoskeletal Disorders. 10 (1), 1-9 (2009).</li><li>Palazzo, C., 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=Barriers+to+home-based+exercise+program+adherence+with+chronic+low+back+pain:+Patient+expectations+regarding+new+technologies.">Barriers to home-based exercise program adherence with chronic low back pain: Patient expectations regarding new technologies.</a> Annals of Physical and Rehabilitation Medicine. 59 (2), 107-113 (2016).</li><li>Lunt, H., 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=High+intensity+interval+training+in+a+real+world+setting:+a+randomized+controlled+feasibility+study+in+overweight+inactive+adults,+measuring+change+in+maximal+oxygen+uptake.">High intensity interval training in a real world setting: a randomized controlled feasibility study in overweight inactive adults, measuring change in maximal oxygen uptake.</a> PloS One. 9 (1), 83256 (2014).</li><li>Jung, M. E., 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=Cardiorespiratory+fitness+and+accelerometer-determined+physical+activity+following+one+year+of+free-living+high-intensity+interval+training+and+moderate-intensity+continuous+training:+a+randomized+trial.">Cardiorespiratory fitness and accelerometer-determined physical activity following one year of free-living high-intensity interval training and moderate-intensity continuous training: a randomized trial.</a> International Journal of Behavioral Nutrition and Physical Activity. 17 (1), 1-10 (2020).</li><li>Taylor, J. L., 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=Guidelines+for+the+delivery+and+monitoring+of+high+intensity+interval+training+in+clinical+populations.">Guidelines for the delivery and monitoring of high intensity interval training in clinical populations.</a> Progress in Cardiovascular Diseases. 62 (2), 140-146 (2019).</li><li>Grip, F., 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=HIIT+is+superior+than+MICT+on+cardiometabolic+health+during+training+and+detraining.">HIIT is superior than MICT on cardiometabolic health during training and detraining.</a> European Journal of Applied Physiology. 121 (1), 159-172 (2021).</li></ol>

HIIT has become a time-efficient alternative to the traditional MICT. This studypresents a low-cost, easy-to-implement HIIT protocol for a real-world setting. Most studies have proven the health benefits of HIIT using laboratory-based HIIT protocols6,10, and, recently, few studies have investigated the effects of real-world HIIT protocols in overweight untrained individuals10,14.
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Robust evidence has shown that High-Intensity Interval Training (HIIT) induces similar or even superior positive physiological adaptations than a traditional long-duration Moderate-Intensity Continuous Training (MICT)1,2,3. A HIIT session is composed of short bouts of high-intensity exercise interspersed with low-intensity exercise (active recovery) or rest (passive recovery). While a daily session with a MICT protocol lasts 30 to 60 min, on average, a daily session with HIIT may take half the time or less from a MICT session. Then, considering that sedentary individuals have indicated lack of time as the main barrier to engaging in a regular physical exercise program4, HIIT may be an interesting time-efficient approach to increase exercise adherence and improve health5.
However, despite the growing evidence pointing out the health benefits of HIIT, most studies have designed HIIT protocols for well-controlled laboratory environments using high-cost specialized equipment, such as treadmills and cycle ergometers. In the last 5 years, some studies have emphasized the importance of new studies confirming the health benefits of HIIT using exercise protocols for the real world, e.g., HIIT protocols performed in outdoor spaces without specialized equipment6. However, the difficulty in designing well-controlled studies to test HIIT protocols in non-laboratory environments has been the main challenge for researchers in this field.
In response to this challenge, a real-world HIIT protocol was developed here for scientific research and its efficiency in cardiorespiratory fitness was tested. A training protocol was developed using the shuttle test proposed by Leger et al.7 (named as Beep Training), and the effects of HIIT and MICT regiments based on this Beep training on VO2 max were compared in overweight untrained men. Briefly, although the duration of daily sessions with HIIT was almost half of the duration of MICT protocol, the Beep Training with HIIT was superior to the Beep Training with MICT in increasing VO2 max. Thus, Beep training with HIIT is a time-efficient and feasible approach to improve cardiorespiratory fitness in apparently healthy overweight/obese individuals. Moreover, general people may easily practice the beep training protocol as it is a low-cost and easy-to-implement physical training in a real-world scenario.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Beep Test software&#160;</td>
			<td>Bitworks</td>
			<td>N/A</td>
			<td>version 2.0</td>
		</tr>
		<tr>
			<td>Exercise Physiology Measurement &#38; Analysis System</td>
			<td>ADI INSTRUMENT</td>
			<td>PL3508B80</td>
			<td>PowerLab 8/35 and LabChart Pro software (which includes the Metabolic Module for calculating metabolic parameters such as VCO2, VO2, respiratory exchange ratio (RER) and minute ventilation) 
			Bio Amp 
			Gas Analyzer 
			Gas Mixing Chamber 
			Spirometer 
			Thermistor Pod 
			Exercise Physiology Accessory Kit</td>
		</tr>
		<tr>
			<td>GraphPad Software</td>
			<td>GraphPad Prism</td>
			<td>N/A</td>
			<td>version 7.00</td>
		</tr>
		<tr>
			<td>Heart Rate monitor</td>
			<td>Polar</td>
			<td>N/A</td>
			<td>RS800 Running Computer: The running computer displays and records your heartrate and other exercise data during exercise. 2. Polar WearLink W.I.N.D. transmitter: The transmitter sends the heart rate signal to the running computer. The transmitterconsists of a connector and a strap.</td>
		</tr>
		<tr>
			<td>Sound Forge PRO software</td>
			<td>Sound Forge</td>
			<td>N/A</td>
			<td>version 14.00</td>
		</tr>
		<tr>
			<td>Treadmill</td>
			<td>IMBRASPORT</td>
			<td>N/A</td>
			<td>Speed from 0 to 24 km/h. 
			Elevation from 0 to 26%. 
			Weight capacity for users up to 220 kg. 
			4 hp motor (220 v). 
			Automatic lubrication system. 
			With Safety Key and Emergency Stop Button. 
			Runs 14 preset protocols: Bruce, Modified Bruce, mini Bruce, Naughton Ellestad, Balke, Balke-Ware, Astrand, Cooper, Kattus, Male Mader, Female Mader, Stanford and Modified Stanford. 
			Run RAMP PROTOCOL.</td>
		</tr>
	</tbody>
</table>

a real-world high-intensity interval training protocol for cardiorespiratory fitness improvement

High-Intensity Interval Training (HIIT) has emerged as an interesting time-efficient approach to increase exercise adherence and improve health. However, few studies have tested the efficiency of HIIT protocols in a &#34;real world&#34; setting, e.g., HIIT protocols designed for outdoor spaces without specialized equipment. This study presents a &#34;real world&#34; training protocol, named &#34;beep training&#34;, and compares the efficiency of a HIIT regiment versus a traditional long-duration Moderate-Intensity Continuous Training (MICT) regiment using this beep training protocol on VO2 max of overweight untrained men. Twenty-two subjects performed outdoor running with MICT (n = 11) or HIIT (n = 11). Cardiorespiratory fitness was assessed before and after training protocols using a metabolic analyzer. Both training protocols were performed 3 days a week for 8 weeks using the Beep Test results. The MICT group performed the exercise program at 60%-75% of the maximum speed of the 20 m shuttle test (Vmax) and with a progression of the distance of 3,500-5,000 m. The HIIT group performed the interval exercise with 7-10 bouts of 200 m at 85%-100% of the maximum speed of the 20 m shuttle test (Vmax), interspersed with 1 min of passive recovery. Although the HIIT group presented a significantly lower training volume than the MICT group (p &#60; 0.05) after 8 weeks of beep training, HIIT was superior to MICT in improving VO2 max (MICT: ~4.1%; HIIT: ~7.3%; p &#60; 0.05). The &#34;real world&#34; HIIT regiment based on beep training protocol is a time-efficient, low-cost, and easy-to-implement protocol for overweight untrained men.

Table 1 shows data of distance, speed, rest time, session duration, and mean heart rate from HIIT and MICT groups. During the 8 weeks of beep training, running distance and duration were higher in MICT than in the HIIT group (p &#60; 0.05), while running velocity and heart rate were higher in HIIT than in the MICT group (p &#60; 0.05). These data confirm the main differences between MICT and HIIT protocols, i.e., while MICT is characterized by long-duration moderate-intensity continuous exercises, HIIT i...

Watch this Scientific Journal Video about A Real-World High-Intensity Interval Training Protocol for Cardiorespiratory Fitness Improvement at JoVE.com

A Real-World High-Intensity Interval Training Protocol for Cardiorespiratory Fitness Improvement

This study presents a low-cost and easy-to-implement "real world" high-intensity interval training (HIIT) protocol for scientific research and discusses its efficiency for cardiorespiratory fitness.

High-Intensity Interval Training (HIIT) has emerged as an interesting time-efficient approach to increase exercise adherence and improve health. However, ...

Despite that growing evidence points out the health benefits of high-intensity interval training, most studies have designed its protocol for well-controlled laboratory environments using high-cost, specialized equipment such as treadmills and cyclometers. The high intensity interval training based on beep training is a feasible, time-efficient, low-cost, and easy-to-implement protocol designed to be practiced in a real world setting. The high intensity interval training based on beep training may help in the prevention and treatment of several cardiometabolic diseases such as diabetes, hypertension, and obesity.This is a real world exercise protocol developed to be used not only in scientific research in the field of exercise science, but also to be practiced for apparently healthy individuals. To practice this high intensity interval training protocol, it's essential to take advice from a professional of physical exercise. Begin by familiarizing the participant with the treadmill and mouthpiece used on the metabolic analyzer for at least 24 hours before testing.Calibrate the metabolic analyzer according to the manufacturer's recommendations. Use a heart rate monitor to measure the participant's heart rate. Place the non-rebreathing unilateral mouthpiece on the participant, and ensure that the mouth and nose are completely covered.Then turn on the treadmill, select the ramp protocol, and enter the subject's physical activity level to program the speed and degree of maximal metabolic equivalent increments. Press on"to start the ramp protocol. The program starts with a warmup of three minutes at five kilometers per hour.Record the heart rate and rating of perceived exertion every minute of the test using the Borg scale 6 to 20. After achieving the maximal oxygen uptake, return the treadmill speed to five kilometers per hour, and ask the participant to remain on the treadmill for an additional three minutes. Turn off the treadmill, and remove the mouthpiece from the participant.In the beep test, choose a flat surface to place two cones 20 meters apart. Orient the participant to run 20 meters within a predetermined period, signaled by a beep sound produced by a software developed for this test. Adjust the sound equipment connected to the computer with the software.After familiarizing the participant with the test, start the test. When the participant can no longer complete the 20 meter run within the time stipulated by the beep sound, end the test. For moderate intensity continuous training protocol, instruct the participant to maintain correct running speed and distance by periodically checking the clock speed and distance according to the GPS from the heart rate monitor.Ask the participant to complete a five-minute warmup by performing dynamic stretches and walking before each exercise session. Then put on a heart rate monitor equipped with GPS tracking and start the exercise session. Train the participants once a day, three times a week, either in the morning or afternoon.Initially, train the participants for two weeks at 60%of the individual maximum speed achieved during the 20-meter test, covering a distance of 3, 500 meters per session in the first week, and 4, 000 meters per session in the second week. Then, train the participants for four weeks at 65%of the maximum speed, covering a distance of 4, 000 meters per session in the third week, 4, 500 meters per session in the fourth and fifth week, and 5, 000 meters per session in the sixth week. In the seventh week, train the participants at 70%of maximum speed, covering a distance of 5, 000 meters per session.Then, in the eighth week, at 75%of maximum speed, covering a distance of 5, 000 meters per session. After each exercise session, transfer the data recorded by the heart rate monitor to a computer to verify if the prescribed distance and running speed were reached. Exclude the participants who do not complete all the training sessions in the week.Analyze the data to ensure that each participant performs the respective training regimen according to the prescribed distance and speed. For the high-intensity interval training protocol, mark a lane with cones every 20 meters. Then instruct the participant to follow the beep sound command to know the exact moment to reach the cone.After performing a five minute warmup, put on a heart rate monitor equipped with GPS, and start the exercise session. Train the participant once a day, three times a week, either in the morning or afternoon. In the first week, train the participant with seven sprints of 200 meters at 85%of maximum speed, interspersed by one minute of passive recovery between sprints.Train the participant with eight sprints in the second week. Then, train the participant with eight sprints in the third week, nine sprints in the fourth and fifth week, and 10 sprints in the sixth week, performed at 90%maximum speed for 200 meters, interspersed by one minute of passive recovery. In the seventh week, train the participants with 10 sprints of 200 meters at 95%maximum speed, and then 100%maximum speed with 10 sprints in the eighth week.After the exercise session, transfer the data recorded by the heart rate monitor to a computer, and exclude the participants who did not complete all the training sessions in the week. Finally, analyze the data to ensure that each participant performs the respective training regimen according to the prescribed distance and speed. In the representative analysis, the comparison of distance, speed, rest time, session duration, and mean heart rate from the moderate intensity continuous training and the high intensity interval training groups during eight weeks of training is shown.The running distance and duration were higher in moderate intensity continuous training than in the high intensity interval training group. In contrast, the running velocity and heart rate were higher in high intensity interval training than in the moderate intensity continuous training group. Before training, the maximal oxygen uptake was similar in the high intensity interval training and moderate intensity continuous training groups.After the beep training, the maximal oxygen uptake increased in both the groups. However, the increase was superior in high intensity interval training versus the moderate intensity continuous training group. The visual demonstration of this method is critical for a step-by-step comprehension of how a person must practice each daily exercise session of the beep training.Future studies must be performed to test the efficiency and feasibility of beep training in healthy and unhealthy individuals of different ages.

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