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High-intensity interval exercise induces 24-h energy expenditure similar to traditional endurance exercise despite reduced time commitment

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Subjects performed high-intensity interval training (HIIT) and continuous moderate-intensity training (END) to evaluate 24-h oxygen consumption. Oxygen consumption during HIIT was lower versus END; however, total oxygen consumption over 24 h was similar. These data demonstrate that HIIT and END induce similar 24-h energy expenditure, which may explain the comparable changes in body composition reported despite lower total training volume and time commitment.
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... CrossFit, which is one of the training models that has become widespread recently, is a training practice consisting constantly changing, high-intensity, multijointed movements. The main target of this training model is to create a broad, common, and very comprehensive training method (10). The content of CrossFit is also described as combined training and is recommended in terms of strength and power training to use the time efficiently (11). ...
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ABSTRACT Purpose: In this study, it was aimed to examine the effects of the 16-week CrossFit Cindy exercise model on some physical and physiological fitness parameters. Methods: In this study; mean age 39.87±8.21 years, average height 164.07±9.16 cm, body weight averages 87.40±12.05 kg, BMI averages 30.71±4.79 kg/m2 and during the last 6 months 15 overweight middle aged women who did not regular exercise participated voluntarily. Participants were applied CrossFit exercise (cindy method) 4 session a week for 16 weeks regularly. Participants' body composition, cardiovascular fitness and physical physiological fitness parameters were measured before and after exercise period. Variance homogeneity of the data was performed using Levene’s Test and normal distribution analyzes were performed with Shapiro-Wilk Test. Paired Sample T Test was used in the analysis of all parameters. Significance was determined at the level of p> 0.05. Results: As a result of exercise interventions in overweight middle aged women, statistical changes were observed in the body composition, resting heart rate, oxygen consumption maximal strength and flexibility values of the participants. Conclusion: The findings suggest that CrossFit Cindy model can be used an alternative high intensity exercise methods that cause positive changes in the body composition and physiological parameters of overweight middle aged women.
... À la suite d'un exercice de type HIIT, l'EPOC est augmenté et pourrait expliquer la perte de MG totale, abdominale dont viscérale (Boutcher 2011). Plusieurs études ont montré qu'un EPOC augmenté, augmentait la DE post-exercice favorisant ainsi la lipolyse adipocytaire après un exercice de type HIIT comparativement à un MICT (Greer et al., 2015;Karstoft et al., 2016;Schaun et al., 2017;Skelly et al., 2014;Wingfield et al., 2015). Cependant d'autres études ne montrent pas ce lien entre EPOC et DE post-exercice (Tucker et al., 2016;Warren et al., 2009) n'expliquant donc pas la majoration de la perte de MG suite à un HIIT par l'augmentation de l'EPOC. ...
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La prévention primaire et secondaire des pathologies inflammatoires chroniques telles que l’obésité et la maladie de Crohn (MC) reposent majoritairement sur des mesures hygiéno-diététiques incluant l’activité physique et la nutrition. Dans le cadre de ce travail de thèse, l’objectif principal était d’étudier l’influence de modalités d’exercice - exercice imposé de type intermittent de haute intensité (HIIT) ou activité de roue spontanée - associé à un apport en lin, riche en acides gras polyinsaturés (AGPI) n-3, sur les interrelations « composition corporelle – inflammation – microbiote intestinal » dans un contexte de pathologies inflammatoires chroniques (obésité, MC) sur modèles murins. Le deuxième objectif était d’étudier spécifiquement deux formes de lin, à travers la graine ou l’huile, afin de déterminer si la matrice de la graine de lin extrudée pouvait avoir des effets qui lui sont propres. Nos résultats indiquent qu’un programme de type HIIT est efficace pour prévenir la prise de poids et de masse grasse, et que le lin, indépendamment de sa forme, diminue l’inflammation. Nos travaux ont également montré un effet majeur du HIIT et de la graine de lin extrudée (TRADILIN, Valorex®) sur la modulation de la composition du microbiote intestinal associé à la muqueuse. Certaines de ces variations étaient corrélées aux modulations de la composition corporelle mais non à l’inflammation. Nos travaux ont montré spécifiquement un effet synergique du HIIT et de l’huile de lin sur l’abondance d’Oscillospira spp. et sur la conversion de l’acide α-linolénique en acide docosahexaénoïque. En conclusion, nos résultats montrent qu’un apport en lin, et particulièrement sous forme de graines extrudées, associé à une activité physique imposée et suffisamment intense, pourraient être efficace dans la prévention et/ou la prise en charge des pathologies inflammatoires chroniques telles que l’obésité et la MC. Les interrelations « composition corporelle – inflammation – microbiote intestinal », restent toutefois à approfondir et les mécanismes sous-jacents à explorer.
... It has been proposed that the total time spent at high intensity is an important criterion to assess the effectiveness of a training program to improve VO 2max (Thevenet et al. 2007a;Midgley et al. 2006;Buchheit and Laursen 2013), and training interventions with traditional HIIE are very effective and time-efficient for developing VO 2max in healthy populations (Midgley et al. 2006;Wen et al. 2019;Gibala 2020). In addition, this training method highly increases EE during and after exercise (Skelly et al. 2014), and could have beneficial effects on body weight and body composition (Keating et al. 2017). ...
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Physical activity is a cornerstone in the treatment of obesity and metabolic syndrome (MetS). Given the leading physical activity barrier of time commitment and safety concerns about vigorous exercise in high-risk groups, this study aimed to investigate the effects of two extremely time-efficient training protocols (< 30 min time effort per week), either performed as high- (HIIT) or moderate-intensity interval training (MIIT) over 12 weeks, in obese MetS patients. In total, 117 patients (49.8 ± 13.6 years, BMI: 38.2 ± 6.2 kg/m ² ) were randomized to HIIT (n = 40), MIIT (n = 37) or an inactive control group (n = 40). All groups received nutritional counseling to support weight loss. Maximal oxygen uptake (VO 2max ), MetS severity (MetS z-score), body composition and quality of life (QoL) were assessed pre-and post-intervention. All groups significantly reduced body weight (~ 3%) but only the exercise groups improved VO 2max , MetS z-score and QoL. VO 2max (HIIT: + 3.1 mL/kg/min, p < 0.001; MIIT: + 1.2 mL/kg/min, p < 0.05) and MetS z-score (HIIT: − 1.8 units, p < 0.001; MIIT: − 1.2 units, p < 0.01) improved in an exercise intensity-dependent manner. In conclusion, extremely low-volume interval training, even when done at moderate intensity, is sufficiently effective to improve cardiometabolic health in obese MetS patients. These findings underpin the crucial role of exercise in the treatment of obesity and MetS.
This systematic review with a meta-analysis was conducted to compare the effects of small-sided games (SSGs)-based interventions with the effects of running-based high-intensity interval training (HIIT) interventions on soccer players’ repeated sprint ability (RSA). The data sources utilized were Web of Science, Scopus, SPORTDiscus, and PubMed. The study eligibility criteria were: (i) parallel studies (SSG-based programs vs. running-based HIIT) conducted in soccer players with no restrictions on age, sex, or competitive level; (ii) isolated intervention programs (i.e., only SSG vs. only running-based HIIT as individual forms) with no restrictions on duration; (iii) a pre–post outcome for RSA; (iv) original, full-text, peer-reviewed articles written in English. An electronic search yielded 513 articles, four of which were included in the present study. There was no significant difference between the effects of SSG-based and HIIT-based training interventions on RSA (effect size (ES) = 0.30; p = 0.181). The within-group analysis revealed no significant effect of SSG-based training interventions (ES = −0.23; p = 0.697) or HIIT-based training interventions (ES = 0.08; p = 0.899) on RSA. The meta-comparison revealed that neither SSGs nor HIIT-based interventions were effective in improving RSA in soccer players, and no differences were found between the two types of training. This suggests that complementary training may be performed to improve the effects of SSGs and HIIT. It also suggests that different forms of HIIT can be used because of the range of opportunities that such training affords.
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Endurance training decreases resting and submaximal heart rate, while maximum heart rate may decrease slightly or remain unchanged after training. The effect of endurance training on various indices of heart rate variability remains inconclusive. This may be due to the use of inconsistent analysis methodologies and different training programmes that make it difficult to compare the results of various studies and thus reach a consensus on the specific training effects on heart rate variability. Heart rate recovery after exercise involves a coordinated interaction of parasympathetic re-activation and sympathetic withdrawal. It has been shown that a delayed heart rate recovery is a strong predictor of mortality. Conversely, endurance-trained athletes have an accelerated heart rate recovery after exercise. Since the autonomic nervous system is interlinked with many other physiological systems, the responsiveness of the autonomic nervous system in maintaining homeostasis may provide useful information about the functional adaptations of the body. This review investigates the potential of using heart rate recovery as a measure of training-induced disturbances in autonomic control, which may provide useful information for training prescription.
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The time constant (T) obtained by fitting post-exercise heart rate (HR) recovery to a first order exponential decay curve has been promoted as an index of parasympathetic activity. However, acceptance has been limited because reported data are inadequate to assess goodness of fit for the model, determine the best exercise protocol, or optimize the duration of post exercise monitoring. Consequently, we evaluated T for nine healthy volunteers (age 24–46) following treadmill exercise at maximal (max) and two stages sub-max exercise (Bruce protocol). T stabilized only after 3 min of post-exercise monitoring. With max exercise, T varied unacceptably with small changes in onset of monitoring, e.g. −16.7±16.6 (−13.2%) in the first 5 s, and residuals of the fitted curve were non-random. In contrast, sub-max exercise produced consistent T values, e.g. −1.9±3.2 (−4.2%) in the first 5 s, and residuals were more nearly random. In conclusion, first order decay is an inadequate model for HR recovery following max exercise, but may be reasonable for sub-max levels.
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Exercise training is a clinically proven, cost-effective, primary intervention that delays and in many cases prevents the health burdens associated with many chronic diseases. However, the precise type and dose of exercise needed to accrue health benefits is a contentious issue with no clear consensus recommendations for the prevention of inactivity-related disorders and chronic diseases. A growing body of evidence demonstrates that high-intensity interval training (HIT) can serve as an effective alternate to traditional endurance-based training, inducing similar or even superior physiological adaptations in healthy individuals and diseased populations, at least when compared on a matched-work basis. While less well studied, low-volume HIT can also stimulate physiological remodelling comparable to moderate-intensity continuous training despite a substantially lower time commitment and reduced total exercise volume. Such findings are important given that 'lack of time' remains the most commonly cited barrier to regular exercise participation. Here we review some of the mechanisms responsible for improved skeletal muscle metabolic control and changes in cardiovascular function in response to low-volume HIT. We also consider the limited evidence regarding the potential application of HIT to people with, or at risk for, cardiometabolic disorders including type 2 diabetes. Finally, we provide insight on the utility of low-volume HIT for improving performance in athletes and highlight suggestions for future research.
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Although several investigations have demonstrated that prolonged aerobic exercise results in decreased left ventricular (LV) function, few have examined the impact of an acute bout of high-intensity exercise on right ventricular (RV) and LV systolic and diastolic function. Cardiac magnetic resonance imaging with tagging was used to study the impact of high-intensity interval exercise on biventricular function in 9 endurance-trained (ET; Vo(2)max 69 +/- 7 ml/kg/min) and 9 normally active (NA; Vo(2)max 44 +/- 9 ml/kg/min) men. Subjects underwent baseline cardiac magnetic resonance imaging assessments (pre) and then performed an average of 14 1-minute intervals at 97 +/- 11% (NA) and 99 +/- 6% (ET) of peak power output, separated by 2 minutes of recovery at 21 +/- 6% (NA) and 21 +/- 9% (ET) of peak power output. After exercise, 2 cardiac magnetic resonance imaging assessments (post 1 at 6.2 +/- 2.6 minutes and post 2 at 38.4 +/- 3.8 minutes) were completed. RV and LV ejection fractions, twist, basal and apical rotation rates, rate of untwisting, circumferential strain, and timings were examined. No significant change in RV and LV ejection fractions, twist, untwisting rate, or strain after exercise occurred in the NA group. In the ET group, RV ejection fraction (pre 56 +/- 4%, post 1 54 +/- 4%, post 2 54 +/- 3%) and LV ejection fraction (pre 62 +/- 4%, post 1 59 +/- 4%, post 2 58 +/- 4%) were decreased at post 1 and post 2, while untwisting rate, apical rotation rate, and circumferential strain were decreased at post 2 (all p values <0.05). In conclusion, biventricular systolic and diastolic dysfunction occurred after 14 minutes of high-intensity exercise in ET athletes, a phenomenon not observed in NA subjects.