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# Defining the number of bouts and oxygen uptake during the “Tabata protocol” performed at different intensities

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## Abstract

It is usually reported that the Tabata protocol (TP) is performed with eight bouts of 20:10 intervals at a load equivalent to 170% of iV̇O2max. However, the feasibility of accumulating 160 s of work at 170% iV̇O2max has been questioned. This article tested the intensity that would allow the performance of the original TP on a cycle ergometer, and measured the highest value of oxygen consumption (V̇O2) obtained during the TP and the time spent above 90% of the maximal oxygen uptake (V̇O2max) during the TP performed at different intensities. Thirteen young active males (25.9 ± 5.5 years, 67.9 ± 9.2 kg, 1.70 ± 0.06 m, 23.6 ± 3.1 kg·m-2) participated in the study. Participants performed a graded exertion test (GXT) on a cycle ergometer to obtain maximum oxygen consumption (V̇O2max) and the intensity associated with V̇O2max (iV̇O2max). V̇O2, maximal heart rate (HRmax), and number of bouts performed were evaluated during the TP performed at 115%, 130%, and 170% of i V̇O2max. V̇O2max, HRmax, and iV̇O2max were 51.8 ± 8.0 mL.kg-1·min-1, 186 ± 10 bpm, and 204 ± 26 W, respectively. The number of bouts performed at 115% (7 ± 1 bouts) was higher than at 130% (5 ± 1 bouts) and 170% (4 ± 1 bouts) (p < .0001). The highest V̇O2 achieved at 115%, 130%, and 170% of iV̇O2max was 54.2 ± 7.9 mL·kg-1·min-1, 52.5 ± 8.1 mL·kg-1·min-1, and 49.6 ± 7.5 mL·kg-1·min-1, respectively. Non significant difference was found between the highest V̇O2 achieved at different intensities, however qualitative magnitude-inference indicate a likely small effect between 115% and 170% of iVO2max. Time spent above 90% of the V̇O2max during the TP at 115% (50 ± 48 s) was higher than 170% (23 ± 21 s; p < 0.044) with a probably small effect. In conclusion, our data suggest that the adequate intensity to perform a similar number of bouts in the original TP is lower than previously proposed, and equivalent to 115% of the iV̇O2max. In addition, intensities between 115 and 130% of the iV̇O2max should be used to raise the time spent above 90% V̇O2max.

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... Não atletas ( et al. (1996), podemos observar a inviabilidade da execução do número de sprints relatados no estudo original, tanto pelos atletas ou não atletas. Este fato já foi motivo de questionamento anteriormente (GENTIL et al. 2016;VIANA et al. 2018) e volta como um ponto a ser discutido. VIANA et al. (2018) também testaram a viabilidade de execução deste protocolo, entretanto, os achados diferem dos encontrados no atual. ...
... Este fato já foi motivo de questionamento anteriormente (GENTIL et al. 2016;VIANA et al. 2018) e volta como um ponto a ser discutido. VIANA et al. (2018) também testaram a viabilidade de execução deste protocolo, entretanto, os achados diferem dos encontrados no atual. Nele, os sujeitos foram capazes de realizar apenas 7 ± 1 sprints em intensidade equivalente a 115%PP, menos do que os sujeitos do presente estudo foram capazes de realizar em intensidade de 130%PP. ...
... The Tabata protocol was originally reported as a type of SIT, involving seven to eight 20-s bouts of high-effort cycling interspersed with 10 s of rest [64]. It is commonly suggested to perform the protocol at a given percentage (110 to 170%) of the intensity associated with maximum oxygen consumption [65,66], which would require specific tests and equipment. However, in the original protocol, exercise was performed at a constant load and was interrupted when the participants were unable to maintain the predetermined intensity [64], which might be more practical. ...
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... As reported by Schuch et al. (43), when considering the available data, aerobic exercise performed three sessions per week over 12 to 24 weeks, delivered in groups, and supervised by an instructor seems to have greater efficacy. In spite of the elevated physiological strain associated with interval training (15,44) and higher contribution from anaerobic metabolism for energy production, interval training is predominantly aerobic (45). Also, training protocols were delivered in groups by a specialized instructor. ...
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... The few studies to date have examined intensity, work time, and training mode. Viana et al. reported that the intensity of HIIT influenced the aerobic metabolic system in relation to the differences in intensity [11]. The authors suggested that the intensity of Tabata's protocol should be applied between 115-130 % of the VO 2max . ...
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... Tabata pada umumnya merupakan latihan dengan intensitas yang tinggi dimana satu kali latihan seseorang akan mendapati pengulangan hingga 6 set, hal ini sangat cukup untuk memberikan hasil untuk meningkatkan performa. (Viana, et al., 2018). ...
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... It should be noted that, for estimating oxygen demand at supramaximal intensity, the relationship between exercise intensity (the work rate) and the submaximal level oxygen uptake measured by an incremental test [e.g., a graded exertion test (GXT)] [32] should not be used. The oxygen uptake at a specific exercise intensity measured by an incremental test procedure, which normally allots an identical time (1-2 min) for each exercise intensity, does not necessarily represents the oxygen uptake or oxygen demand, which is balanced with energy for re-synthesizing the ATP consumed during exercise at the specific intensity. ...
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WISLOFF, U, O. ELLINGSEN, and O.J. KEMI. High-intensity interval training to maximize cardiac benefits of exercise training? Exerc. Sport Sci. Rev., Vol. 37, No. 3, pp. 139-146, 2009. We hypothesized that high-intensity aerobic interval training results in a greater beneficial adaptation of the heart compared with that observed after low-to-moderate exercise intensity. This is supported by recent epidemiological, experimental, and clinical studies. Cellular and molecular mechanisms of myocardial adaptation to exercise training are discussed in this review.
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There is a great demand for perceptual effort ratings in order to better understand man at work. Such ratings are important complements to behavioral and physiological measurements of physical performance and work capacity. This is true for both theoretical analysis and application in medicine, human factors, and sports. Perceptual estimates, obtained by psychophysical ratio-scaling methods, are valid when describing general perceptual variation, but category methods are more useful in several applied situations when differences between individuals are described. A presentation is made of ratio-scaling methods, category methods, especially the Borg Scale for ratings of perceived exertion, and a new method that combines the category method with ratio properties. Some of the advantages and disadvantages of the different methods are discussed in both theoretical-psychophysical and psychophysiological frames of reference.
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Endurance exercise training results in profound adaptations of the cardiorespiratory and neuromuscular systems that enhance the delivery of oxygen from the atmosphere to the mitochondria and enable a tighter regulation of muscle metabolism. These adaptations effect an improvement in endurance performance that is manifest as a rightward shift in the 'velocity-time curve'. This shift enables athletes to exercise for longer at a given absolute exercise intensity, or to exercise at a higher exercise intensity for a given duration. There are 4 key parameters of aerobic fitness that affect the nature of the velocity-time curve that can be measured in the human athlete. These are the maximal oxygen uptake (VO2max), exercise economy, the lactate/ventilatory threshold and oxygen uptake kinetics. Other parameters that may help determine endurance performance, and that are related to the other 4 parameters, are the velocity at VO2max (V-VO2max) and the maximal lactate steady state or critical power. This review considers the effect of endurance training on the key parameters of aerobic (endurance) fitness and attempts to relate these changes to the adaptations seen in the body's physiological systems with training. The importance of improvements in the aerobic fitness parameters to the enhancement of endurance performance is highlighted, as are the training methods that may be considered optimal for facilitating such improvements.
Fibre-specific responses to endurance and low volume high intensity interval training: striking similarities in acute and chronic adaptation, PLoS One Low-active male adolescents: A dose response to high-intensity interval training
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