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Commentary: High-intensity Intermittent Training vs. Moderate-intensity Intermittent Training: Is It a Matter of Intensity or Intermittent Efforts?

DOI:10.3389/fphys.2017.00370
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Paulo Gentil at Universidade Federal de Goiás
Paulo Gentil
Fabricio Del Vecchio at Universidade Federal de Pelotas
Fabricio Del Vecchio
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GENERAL COMMENTARY
published: 30 May 2017
doi: 10.3389/fphys.2017.00370
Frontiers in Physiology | www.frontiersin.org 1May 2017 | Volume 8 | Article 370
Edited by:
Billy Sperlich,
University of Würzburg, Germany
Reviewed by:
Thimo Wiewelhove,
Ruhr University Bochum, Germany
*Correspondence:
Paulo Gentil
paulogentil@hotmail.com
Specialty section:
This article was submitted to
Exercise Physiology,
a section of the journal
Frontiers in Physiology
Received: 12 April 2017
Accepted: 18 May 2017
Published: 30 May 2017
Citation:
Gentil P and Del Vecchio FB (2017)
Commentary: High-intensity
Intermittent Training vs.
Moderate-intensity Intermittent
Training: Is It a Matter of Intensity or
Intermittent Efforts?
Front. Physiol. 8:370.
doi: 10.3389/fphys.2017.00370
Commentary: High-intensity
Intermittent Training vs.
Moderate-intensity Intermittent
Training: Is It a Matter of Intensity or
Intermittent Efforts?
Paulo Gentil 1*and Fabrício B. Del Vecchio 2
1Faculdade de Educação Física e Dança, Universidade Federal de Goiás, Goiânia, Brazil, 2Escola Superior de Educação
Física, Universidade Federal de Pelotas, Pelotas, Brazil
Keywords: high intensity interval exercise, high intensity intermittent training, physical fitness, high intensity
exercise, cardiorespiratory fitness
A commentary on
High-intensity intermittent training versus moderate-intensity intermittent training: is it a
matter of intensity or intermittent efforts?
by Jimenéz-Pavón, D., and Lavie, C. J. (2017). Br. J. Sports Med. doi: 10.1136/bjsports-2016-097015.
[Epub ahead of print]
We read with great interest the article by Jimenéz-Pavón and Lavie (2017). While we agree
with the value of prescribing and studying moderate-intensity interval training (MIIT), there are
important aspects that need to be clarified. The authors raise the point that “intensity” is not the
only difference between high-intensity interval training (HIIT) and aerobic continuous training
(ACT). The authors cite three studies to support the notion that the intermittent nature of the
exercise and not the intensity may be responsible for the results. However, the studies cited do
not seem to support the points raised. Rakobowchuk et al. (2012) trained two groups at the same
intensity (120% of the peak work rate obtained in a ramp-incremental test), but with different
working parameters (repeated intervals of 10:20 s vs. intervals of 30:60 s); therefore, this cannot
be considered a comparison between HIIT and MIIT. In the study conducted by Alkahtani et al.
(2013), the protocols differed in intensity but also in interval duration (5 min vs. 30s). Therefore,
one cannot use the study to make inferences about training intensity as the other parameters were
not equal. Moreover, in the study conducted by Alkahtani et al. (2013), the group that exercised at
higher intensity performed 30 s at 90% of the intensity equivalent to VO2peak, interspersed with
30 s of passive rest. Although this intensity was higher than that performed by the other group (20%
above 45% VO2peak), it is still lower than reported in previous studies using the same interval
duration (Billat et al., 1999, 2000a,b; Billat, 2001a,b; Racil et al., 2013, 2016).
The only study that has really compared different intensities is Racil et al. (2013). The authors
equated the number of bouts, rest intervals, etc. In this study, the decreases in waist circumference,
triglyceride and total cholesterol were significant only in the HIIT group. In addition, increases in
maximal aerobic speed and decreases in percentage of body fat, low-density lipoprotein cholesterol
(LDL-C), and insulin were higher in the HIIT group than in the MIIT group. Although the increases
in VO2peak were significant for both groups (7.7% for HIIT and 5.2 for MIIT), only the HIIT group
showed a significant increase compared to the control group. Therefore, the only study that made
comparisons with different intensities while keeping the other parameters constant clearly favored
HIIT exercises. While this may not answer the question of whether intensity or the intermittent
Gentil and Del Vecchio HIIT vs. MIT: Intensity Matters
nature of interval training is the most important parameter, it
suggests that HIIT promotes better results than MIIT.
We must recall, however, that defining HIIT intensity is not
a matter of “the more the better.” The efficiency of HIIT seems
to be a matter of choosing the adequate intensity. In this regard,
Raleigh et al. (2016) investigated the effects of HIIT intensity on
training-induced adaptations in VO2peak and VO2 kinetics. The
authors compared the effects of HIIT (1 min of effort per 1 min
of rest) targeting 80, 115, or 150% of the intensity equivalent
to VO2max while matching total work performed. According
to the results, increases in VO2peak were greater in the group
that trained at 115% than in the group that trained at 80%. No
differences were observed between the groups that trained at 150
and 80% as well as between the groups that trained at 150 and
115% of iVO2max. The greatest proportion of non-responders
was observed in the group that trained at lower intensity and
the greatest proportion of responders was found in the group
that trained at 115%. Therefore, one should not advocate for or
against high intensity, but rather for adequate intensity.
Jimenéz-Pavón and Lavie (2017) suggested that high-intensity
exercise can sometimes deter physically inactive and unfit people;
however, this has not been found in previous studies. Indeed,
Guiraud et al. (2011) reported that patients with chronic heart
disease preferred HIIT to ACT. Jung et al. (2014) reported that
adults with prediabetes can adhere to HIIT at a level that is
greater than ACT. Furthermore, Jung et al. (2015) compared
HIIT (1 min∼100% W peak and 1 min∼20% W peak for 20 min),
ACT at moderate intensity (∼40% W peak for 40 min) and ACT
at high intensity (∼80% W peak for 20 min). According to the
results, participants reported greater enjoyment related to HIIT
compared to the other protocols and 62% of the participants
reported a preference for engaging in HIIT.
Although we agree that enjoyment ratings might be reduced
when HIIT is strenuous, chronic training may lead to increased
enjoyment due to an increase in achievement. In this regard,
Heisz et al. (2016) randomly assigned sedentary young adults
to HIIT (1 min∼90–95% peak HR followed by 1 min at
30% PPO for a total of 20 min) or ACT (27.5 min∼70–75%
peak HR) for 6 weeks. Enjoyment of HIIT increased with
training, whereas enjoyment of ACT remained constant but
lower.
While we agree that MIIT might be an interesting strategy at
some points and that more studies regarding the topic are needed,
the references presented and the limitations raised by the authors
do not seem to support the points raised.
AUTHOR CONTRIBUTIONS
PG and FD conceived, drafted, and revised the manuscript. All
authors read and approved the final manuscript.
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Chamari, K., et al. (2016). Plyometric exercise combined with high-intensity
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Rossiter, H. B., et al. (2012). Heavy and moderate interval exercise
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2015-0614
Conflict of Interest Statement: The authors declare that the research was
conducted in the absence of any commercial or financial relationships that could
be construed as a potential conflict of interest.
Copyright © 2017 Gentil and Del Vecchio. This is an open-access article distributed
under the terms of the Creative Commons Attribution License (CC BY). The use,
distribution or reproduction in other forums is permitted, provided the original
author(s) or licensor are credited and that the original publication in this journal
is cited, in accordance with accepted academic practice. No use, distribution or
reproduction is permitted which does not comply with these terms.
Frontiers in Physiology | www.frontiersin.org 2May 2017 | Volume 8 | Article 370
... Jimenéz-Pavón [20] suggested that the benefits obtained from HIIT in obesity, health parameters, and cardiovascular disease factors were not due to its intensity, but its intermittent characteristics. However, Gentil and Del Vecchio questioned this by suggesting that the benefits could actually be from the intensity itself [21]. This controversy underlines the complexity associated with interval training, which prevents the drawing of general conclusions [22]. ...
... Our study included MIIT, in which subjects executed a similar protocol to the HIIT group but at moderate intensity, in order to examine whether the benefits of HIIT were due to its intermittency or its intensity. Our findings suggest the MIIT promoted slightly better results in body composition than MICT, but statistically lower than HIIT, which suggests that intensity is an important factor to consider for this outcome, as previously suggested [21]. Indeed, despite the mean difference of only 0.7 kg could not sound meaningful, it is almost two times higher for the more intense protocol. ...
... Indeed, despite the mean difference of only 0.7 kg could not sound meaningful, it is almost two times higher for the more intense protocol. However, the effects of intermittence cannot be neglected, since MIIT was superior to MICT in some aspects, which reinforces previous propositions of the potential benefits [20], whilst confirms that it might be inferior to HIIT [21]. The HIIT group maintained a reduction in fat mass even after 4 weeks of detraining, but the fat mass returned to baseline levels after 2 weeks of detraining in the MICT and MIIT groups, which seem to confirm the potential cardiometabolic risk of detraining [35]. ...
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Background: The present study compared the effects of training and detraining periods of high-intensity interval training (HIIT), moderate-intensity interval training (MIIT) and moderate-intensity continuous training (MICT) on functional performance, body composition, resting blood pressure and heart rate in elderly women nursing home residents. Methods: Forty-six volunteers (age, 80.8 ± 5.2 y; body mass, 69.8 ± 5.2 kg, height, 164.2 ± 4.12 cm) were divided into groups that performed treadmill exercise twice-weekly HIIT (4 bouts of 4-min intervals at 85-95% of the maximal heart rate [HRmax], interspersed by 4 min at 65% HRmax), MIIT (4 bouts of 4 min intervals at 55-75% HRmax, interspersed by 4 min at 45-50% HRmax) and MICT (30-min at 55-75% HRmax). Tests were performed before and after 8 weeks of training and 2 and 4 weeks of detraining. ANCOVA was used to analyze dependent variable changes. Results: After 8 weeks HIIT promoted greater reductions in body mass (HIIT = - 1.6 ± 0.1 kg; MICT = - 0.9 ± 0.1 kg; MIIT = - 0.9 ± 0.1 kg; p = 0.001), fat mass (HIIT = - 2.2 ± 0.1%; MICT = - 0.7 ± 0.1%; MIIT = - 1.2 ± 0.1%; p < 0.001) and resting heart rate (HIIT = - 7.3 ± 0.3%; MICT = - 3.6 ± 0.3%; MIIT = - 5.1 ± 0.3%; p < 0.001) and greater improvement in the chair stand test (HIIT = 3.4 ± 0.1 reps; MICT = 2.5 ± 0.1 reps; MIIT = 3.1 ± 0.1 reps; p < 0.001) when compared to MIIT and MICT. These improvements were sustained after 2 and 4 weeks of detraining only in the HIIT group. Conclusion: HIIT promoted greater benefits for body composition and functional performance than MICT and MIIT and also showed less pronounced effects of detraining. This suggests that the intensity of physical exercise is an important factor to consider when prescribing exercise to the elderly.
View
... We have read the Commentary by Gentil and Del Vecchio (2017), and we are grateful for the interest shown. Exactly, the main objective of our article was to highlight the relevance of prescribing and researching on moderate-intensity interval training (MIIT), although not only this, but in parallel with the current research on high-intensity interval training (HIIT). ...
... Commentary: High-intensity Intermittent Training vs. Moderate-intensity Intermittent Training: Is It a Matter of Intensity or Intermittent Efforts? by Paulo Gentil, P., and Del Vecchio, F. B. (2017). Front. ...
... doi: 10.3389/fphys.2017.00370 We have read the Commentary by Gentil and Del Vecchio (2017), and we are grateful for the interest shown. Exactly, the main objective of our article was to highlight the relevance of prescribing and researching on moderate-intensity interval training (MIIT), although not only this, but in parallel with the current research on high-intensity interval training (HIIT). ...
View
... Considering two recently published meta-analysis 9,15 , we hypothesized that high-intensity exercise promotes higher reductions in BP. Concerning the modality, it seems that interval training may be responsible for better cardiovascular improvements, although it is not a consensus 16,17 . ...
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Background: A family history of arterial hypertension is a significant risk factor for the development of hypertension in youngsters. Thus, primary prevention has been emphasized in those subjects with a genetic predisposition. Methods: This randomized clustered trial aimed to compare the effects of four modalities of aerobic training in postexercise hypotension. The primary outcomes were systolic blood pressure (SBP) and diastolic blood pressure (DBP). Secondly, peak oxygen uptake, heart rate, and subjective perceived exertion were analyzed. Nine normotensive men were randomized in four isocaloric sessions (200 kcal): high-intensity continuous training (HICT), moderate-intensity continuous training (MICT), high-intensity interval training (HIIT), and moderate-intensity interval training (MIIT). Results: The area under the curve (AUC) showed a difference between sessions for SBP (F(3;8)=3.2; P=0.04), with MICT promoting a higher reduction than MIIT (P<0.05). In DBP there was also a difference (F(3;8)=15.3; P<0.001), with HICT reducing more than HIIT (P<0.05) and MIIT (P<0.05). Moderate-intensity protocols provided clinically relevant changes (CRC) in 11.1% of the individuals, and high-intensity protocols presented CRC in 50% of them (χ2=6.41; P=0.011) for SBP. For DBP, there was CRC in 27.8% of continuous conditions and none in the intervals (χ2=5.81; P=0.016). Conclusions: All training sessions promoted postexercise hypotension for DBP, and HICT provided higher reductions in the AUC. CRC for SBP were observed according to the intensity, while CRC for DBP were associated with modality.
View
... These are critical processes for improving the acquisition of new skills, learning, and memory, and therefore have important implications in clinical populations such as stroke (Bliss and Cooke, 2011;Zeiler and Krakauer, 2013). Presently, there is a focus on determining the specifics of aerobic exercise prescription to optimally prime the brain (Ploughman et al., 2005Singh et al., 2014;Robertson et al., 2015;Saucedo Marquez et al., 2015;Hwang et al., 2016;Charalambous et al., 2017;Gentil and Del Vecchio, 2017;Morais et al., 2017;Nepveu et al., 2017;Neva et al., 2017). The benefits of aerobic exercise appear to be intensity dependent (Ploughman et al., 2007b;Hasan et al., 2016; and several studies have shown that delivering high-intensity aerobic exercise Abbreviations: CSE, corticospinal excitability; FDI, first dorsal interosseous; HIIT, high intensity interval training; MAS, Modified Ashworth Scale; MEP, motor evoked potential; MICE, moderate, constant-load exercise; MSO, maximal stimulator output; NIHSS, National Institute of Health Stroke Scale; TMS, transcranial magnetic stimulation; VCO 2 , volume of dioxide oxygen; VO 2 , volume of oxygen; VO 2max , maximal volume of oxygen uptake. ...
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Objective: Evaluate intensity-dependent effects of a single bout of high intensity interval training (HIIT) compared to moderate intensity constant-load exercise (MICE) on corticospinal excitability (CSE) and effects on upper limb performance in chronic stroke. Design: Randomized cross-over trial. Setting: Research laboratory in a tertiary rehabilitation hospital. Participants: Convenience sample of 12 chronic stroke survivors. Outcome measures: Bilateral CSE measures of intracortical inhibition and facilitation, motor thresholds, and motor evoked potential (MEP) latency using transcranial magnetic stimulation. Upper limb functional measures of dexterity (Box and Blocks Test) and strength (pinch and grip strength). Results: Twelve (10 males; 62.50 ± 9.0 years old) chronic stroke (26.70 ± 23.0 months) survivors with moderate level of residual impairment participated. MEP latency from the ipsilesional hemisphere was lengthened after HIIT (pre: 24.27 ± 1.8 ms, and post: 25.04 ± 1.8 ms, p = 0.01) but not MICE (pre: 25.49 ± 1.10 ms, and post: 25.28 ± 1.0 ms, p = 0.44). There were no significant changes in motor thresholds, intracortical inhibition or facilitation. Pinch strength of the affected hand decreased after MICE (pre: 8.96 ± 1.9 kg vs. post: 8.40 ± 2.0 kg, p = 0.02) but not after HIIT (pre: 8.83 ± 2.0 kg vs. post: 8.65 ± 2.2 kg, p = 0.29). Regardless of type of aerobic exercise, higher total energy expenditure was associated with greater increases in pinch strength in the affected hand after exercise (R2 = 0.31, p = 0.04) and decreases in pinch strength of the less affected hand (R2 = 0.26 p = 0.02). Conclusion: A single bout of HIIT resulted in lengthened nerve conduction latency in the affected hand that was not engaged in the exercise. Longer latency could be related to the cross-over effects of fatiguing exercise or to reduced hand spasticity. Somewhat counterintuitively, pinch strength of the affected hand decreased after MICE but not HIIT. Regardless of the structure of exercise, higher energy expended was associated with pinch strength gains in the affected hand and strength losses in the less affected hand. Since aerobic exercise has acute effects on MEP latency and hand strength, it could be paired with upper limb training to potentiate beneficial effects.
View
... These are critical processes for improving the acquisition of new skills, learning, and memory, and therefore have important implications in clinical populations such as stroke (Bliss and Cooke, 2011;Zeiler and Krakauer, 2013). Presently, there is a focus on determining the specifics of aerobic exercise prescription to optimally prime the brain (Ploughman et al., 2005Singh et al., 2014;Robertson et al., 2015;Saucedo Marquez et al., 2015;Hwang et al., 2016;Charalambous et al., 2017;Gentil and Del Vecchio, 2017;Morais et al., 2017;Nepveu et al., 2017;Neva et al., 2017). The benefits of aerobic exercise appear to be intensity dependent (Ploughman et al., 2007b;Hasan et al., 2016; and several studies have shown that delivering high-intensity aerobic exercise Abbreviations: CSE, corticospinal excitability; FDI, first dorsal interosseous; HIIT, high intensity interval training; MAS, Modified Ashworth Scale; MEP, motor evoked potential; MICE, moderate, constant-load exercise; MSO, maximal stimulator output; NIHSS, National Institute of Health Stroke Scale; TMS, transcranial magnetic stimulation; VCO 2 , volume of dioxide oxygen; VO 2 , volume of oxygen; VO 2max , maximal volume of oxygen uptake. ...
A Bout of High Intensity Interval Training Lengthened Nerve Conduction Latency to the Non-exercised Affected Limb in Chronic Stroke
Article
Full-text available
  • Jul 2018
Objective: Evaluate intensity-dependent effects of a single bout of high intensity interval training (HIIT) compared to moderate intensity constant-load exercise (MICE) on corticospinal excitability (CSE) and effects on upper limb performance in chronic stroke. Design: Randomized cross-over trial. Setting: Research laboratory in a tertiary rehabilitation hospital. Participants: Convenience sample of 12 chronic stroke survivors. Outcome measures: Bilateral CSE measures of intracortical inhibition and facilitation, motor thresholds, and motor evoked potential (MEP) latency using transcranial magnetic stimulation. Upper limb functional measures of dexterity (Box and Blocks Test) and strength (pinch and grip strength). Results: Twelve (10 males; 62.50 ± 9.0 years old) chronic stroke (26.70 ± 23.0 months) survivors with moderate level of residual impairment participated. MEP latency from the ipsilesional hemisphere was lengthened after HIIT (pre: 24.27 ± 1.8 ms, and post: 25.04 ± 1.8 ms, p = 0.01) but not MICE (pre: 25.49 ± 1.10 ms, and post: 25.28 ± 1.0 ms, p = 0.44). There were no significant changes in motor thresholds, intracortical inhibition or facilitation. Pinch strength of the affected hand decreased after MICE (pre: 8.96 ± 1.9 kg vs. post: 8.40 ± 2.0 kg, p = 0.02) but not after HIIT (pre: 8.83 ± 2.0 kg vs. post: 8.65 ± 2.2 kg, p = 0.29). Regardless of type of aerobic exercise, higher total energy expenditure was associated with greater increases in pinch strength in the affected hand after exercise (R2 = 0.31, p = 0.04) and decreases in pinch strength of the less affected hand (R2 = 0.26 p = 0.02). Conclusion: A single bout of HIIT resulted in lengthened nerve conduction latency in the affected hand that was not engaged in the exercise. Longer latency could be related to the cross-over effects of fatiguing exercise or to reduced hand spasticity. Somewhat counterintuitively, pinch strength of the affected hand decreased after MICE but not HIIT. Regardless of the structure of exercise, higher energy expended was associated with pinch strength gains in the affected hand and strength losses in the less affected hand. Since aerobic exercise has acute effects on MEP latency and hand strength, it could be paired with upper limb training to potentiate beneficial effects.
View
... Therefore, the same percentage of HR max and i _ VO 2max can result in different intensities, and studies involving different methods for controlling intensity could lead to different results, even when adopting the same number of bouts and the same effort and pause times. The adequate definition and interpretation of training intensity seems to be vital, since the results of IT are largely dependent on it [46]. For example, Racil et al. [47] compared the effects of IT intensity in groups of obese young females performing the same number of bouts with the same total time and time:effort ratios (6-8 9 30:30 s). ...
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Interval training (IT) has been used for many decades with the purpose to increase performance and promote health benefits while demanding a relatively small amount of time. IT can be defined as intermittent periods of intense exercise separated by periods of recovery and has been divided into high-intensity interval training (HIIT), sprint interval training (SIT) and repeated sprint training (RST). IT use resulted in the publication of many studies and many of them with conflicting results and positions. The aim of this article was to move forward and understand studies’ protocol in order to draw accurate conclusions, as well as to avoid previous mistakes and effectively reproduce previous protocols. When analyzing the literature, we found many inconsistencies, such as, the controversial concept of ‘supramaximal’ effort, a misunderstanding regarding the term ‘high intensity’ and the use of different strategies to control intensity. The adequate definition and interpretation of training intensity seems to be vital, since the results of IT are largely dependent on it. These observations are only a few examples of the complexity involved with IT prescription, discussed to illustrate some problems with the current literature regarding IT. Therefore, it is our opinion that it is not possible to draw general conclusions about IT without considering all variables used in IT prescription, such as, exercise modality, intensity, effort andrest times and participants’ characteristics. In order to help guide researchers and health professionals in their practices it is important that experimental studies report their methods in as much detail as possible and future reviews and meta-analyses should critically discuss the articles included in light of their methods to avoid inadequate generalizations.
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... There is little agreement on the extent to which the benefits of HIIT can be attributed to the exercise intensity alone among the other load variables [12,13]. Training at both moderate to high (70-80%) and near-maximal (>90%) intensity can significantly improve health parameters [13]. ...
Very Low Volume High-Intensity Interval Exercise Is More Effective in Young Than Old Women
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We investigated the acute neuromuscular and stress responses to three different high-intensity interval training sessions in young (age 19.5±1.3 years) and older (age 65.7±2.8 years) women. Cycling exercise comprised either 6 × 5 s or 3 × 30 s all-out, or 3 × 60 s submaximal, efforts each performed 5 weeks apart in randomized order. Peak and average power was higher in young than in older women and was largest during the 6 × 5 s strategy in both groups ( p<0.05 ). The decrease in the ratio of torques evoked by 20 and 100 Hz electrical stimulation, representing low-frequency fatigue, was more evident after the 3 × 30 and 3 × 60 s than the 6 × 5 s bout in both groups and was larger in young than in older women ( p<0.05 ). Both groups preferred 6 × 5 s cycling for further training. In conclusion, in young women, very low volume (6 × 5 s) all-out exercise induces significant physiological stress and seems to be an effective means of training. For older women, longer exercise sessions (3 × 60 s) are more stressful than shorter ones but are still tolerable psychologically.
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Effects of the intensity of interval training on aerobic fitness, body composition and resting metabolic rate of women with overweight or obesity: A randomized trial
Article
  • Oct 2022
BACKGROUND: Moderate-intensity interval training (MIIT) may be a viable exercise format for improving body composition, aerobic fitness, and health-related variables. OBJECTIVES: This randomized trial aimed to analyze the effect of MIIT or high-intensity interval training (HIIT) on aerobic fitness, body composition variables, and resting metabolic rate (RMR) in women with overweight or obesity. METHODS: 31 sedentary adult women with overweight or obesity performed 7 weeks × 3 weekly sessions of either HIIT or MIIT. Physical and physiological tests were applied before and after training. RESULTS: In both analyses (intention-to-treat and by adherence to the training), aerobic fitness showed a time effect (p= 0.041 and p= 0.015), but without differences between groups (p> 0.05). No group (HIIT vs. MIIT), time (pre vs. post), or interaction effects (group vs. time) were found for RMR, body composition markers (fat mass, body fat percentage, lean mass), or body mass index – BMI (p> 0.05). In addition, MIIT induced a relatively high drop-out rate. CONCLUSIONS: This study suggested that the short-term (7-weeks) interval exercise training was effective for increasing aerobic fitness, and moderate-intensity intervals were as effective as high-intensity intervals. However, neither training format was effective for changing RMR, body composition variables, or BMI of women with overweight or obesity. Clinical trial ID: RBR-9jd7b7.
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Enjoyment for High-Intensity Interval Exercise Increases during the First Six Weeks of Training: Implications for Promoting Exercise Adherence in Sedentary Adults
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This is the first study to show that enjoyment for high-intensity interval exercise increases with chronic training. Prior acute studies typically report high-intensity interval training (HIT) as being more enjoyable than moderate continuous training (MCT) unless the high-intensity intervals are too strenuous or difficult to complete. It follows that exercise competency may be a critical factor contributing to the enjoyment of HIT, and therefore building competency through chronic training may be one way to increase its enjoyment. To test this, we randomly assigned sedentary young adults to six weeks of HIT or MCT, and tracked changes in their enjoyment for the exercise. Enjoyment for HIT increased with training whereas enjoyment for MCT remained constant and lower. Changes in exercise enjoyment were predicted by increases in workload, suggesting that strength adaptions may be important for promoting exercise enjoyment. The results point to HIT as a promising protocol for promoting exercise enjoyment and adherence in sedentary young adults. © 2016 Heisz et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
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Plyometric exercise combined with high-intensity interval training improves metabolic abnormalities in young obese females more so than interval training alone
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Full-text available
  • Oct 2015
The aim of this study was to compare the effects of 12 weeks of high-intensity interval training (HIIT) with the effects of 12 weeks of plyometric exercise combined with HIIT (P+HIIT) on anthropometric, biochemical, and physical fitness data in young obese females. Sixty-eight participants (age, 16.6 ± 1.3 y; body mass, 82.8 ± 5.0 kg; body fat, 39.4% ± 3.3%; body mass index z score, 2.9 ± 0.4) were assigned to 1 of 3 groups: HIIT (2 blocks per session of 6-8 bouts of 30-s runs at 100% velocity at peak oxygen uptake, with 30-s active recovery between bouts at 50%velocity at peak oxygen uptake (n = 23)); P+HIIT (2 blocks per session of 3 different 15-s plyometric exercises with 15-s passive recoveries, totaling 2 min for each plyometric exercise + the same HIIT program (n = 26)); or control (no exercise (n = 19)). Anthropometric (body mass, body mass index z score, body fat, lean body mass, and waist circumference), biochemical (plasma glucose, insulin, leptin and adiponectin concentrations, leptin/adiponectin ratio, and homeostasis model assessment of insulin resistance (HOMA-IR)), physical fitness (peak oxygen uptake, velocity at peak oxygen uptake, squat jump, and countermovement jump performances), and energy intake data were collected. Both training programs improved the anthropometric, biochemical, and physical fitness variables. However, the P+HIIT program induced greater improvements than did the HIIT program in lean body mass (+3.0% ± 1.7%), plasma glucose and leptin concentrations (-11.0% ± 4.7% and -23.8% ± 5.8%, respectively), plasma leptin/adiponectin ratio (-40.9% ± 10.9%), HOMA-IR (-37.3% ± 6.2%), and squat jump performance (22.2% ± 7.5%). Taken together, these findings suggest that adding plyometric exercises to a HIIT program may be more beneficial than HIIT alone in obese female adolescents.
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High-Intensity Interval Training as an Efficacious Alternative to Moderate-Intensity Continuous Training for Adults with Prediabetes
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  • Mar 2015
Aims: High-intensity interval training (HIIT) leads to improvements in various markers of cardiometabolic health but adherence to HIIT following a supervised laboratory intervention has yet to be tested. We compared self-report and objective measures of physical activity after one month of independent exercise in individuals with prediabetes who were randomized to HIIT (n = 15) or traditional moderate-intensity continuous training (MICT, n = 17). Method: After completing 10 sessions of supervised training participants were asked to perform HIIT or MICT three times per week for four weeks. Results: Individuals in HIIT (89 ± 11%) adhered to their prescribed protocol to a greater extent than individuals in MICT (71 ± 31%) as determined by training logs completed over one-month follow-up (P = 0.05, Cohen's d = 0.75). Minutes spent in vigorous physical activity per week measured by accelerometer were higher in HIIT (24 ± 18) as compared to MICT (11 ± 10) at one-month follow-up (P = 0.049, Cohen's d = 0.92). Cardiorespiratory fitness and systolic blood pressure assessed at one-month follow-up were equally improved (P's < 0.05). Conclusions: This study provides preliminary evidence that individuals with prediabetes can adhere to HIIT over the short-term and do so at a level that is greater than MICT.
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Where Does HIT Fit? An Examination of the Affective Response to High-Intensity Intervals in Comparison to Continuous Moderate- and Continuous Vigorous-Intensity Exercise in the Exercise Intensity-Affect Continuum
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Affect experienced during an exercise session is purported to predict future exercise behaviour. Compared to continuous moderate-intensity exercise (CMI), the affective response to continuous vigorous-intensity exercise (CVI) has consistently been shown to be more aversive. The affective response, and overall tolerability to high-intensity interval training (HIT), is less studied. To date, there has yet to be a comparison between HIT, CVI, and CMI. The purpose of this study was to compare the tolerability and affective responses during HIT to CVI and CMI. This study utilized a repeated measures, randomized, counter-balanced design. Forty-four participants visited the laboratory on four occasions. Baseline fitness testing was conducted to establish peak power output in Watts (Wpeak). Three subsequent visits involved a single bout of a) HIT, corresponding to 1-minute at ∼100% Wpeak and 1-minute at ∼20% Wpeak for 20 minutes, b) CMI, corresponding to ∼40% Wpeak for 40 minutes, and c) CVI, corresponding to ∼80% Wpeak for 20 minutes. The order of the sessions was randomized. Affective responses were measured before, during and after each session. Task self-efficacy, intentions, enjoyment and preference were measured after sessions. Participants reported greater enjoyment of HIT as compared to CMI and CVI, with over 50% of participants reporting a preference to engage in HIT as opposed to either CMI or CVI. HIT was considered more pleasurable than CVI after exercise, but less pleasurable than CMI at these times. Despite this participants reported being just as confident to engage in HIT as they were CMI, but less confident to engage in CVI. This study highlights the utility of HIT in inactive individuals, and suggests that it may be a viable alternative to traditionally prescribed continuous modalities of exercise for promoting self-efficacy and enjoyment of exercise.
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Effect of interval training intensity on fat oxidation, blood lactate and the rate of perceived exertion in obese men
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Full-text available
  • Oct 2013
Purpose The objectives of this study were to examine the effect of 4-week moderate- and high-intensity interval training (MIIT and HIIT) on fat oxidation and the responses of blood lactate (BLa) and rating of perceived exertion (RPE). Methods Ten overweight/obese men (age = 29 ±3.7 years, BMI = 30.7 ±3.4 kg/m2) participated in a cross-over study of 4-week MIIT and HIIT training. The MIIT training sessions consisted of 5-min cycling stages at mechanical workloads 20% above and 20% below 45%VO2peak. The HIIT sessions consisted of intervals of 30-s work at 90%VO2peak and 30-s rest. Pre- and post-training assessments included VO2max using a graded exercise test (GXT) and fat oxidation using a 45-min constant-load test at 45%VO2max. BLa and RPE were also measured during the constant-load exercise test. Results There were no significant changes in body composition with either intervention. There were significant increases in fat oxidation after MIIT and HIIT (p ≤ 0.01), with no effect of intensity. BLa during the constant-load exercise test significantly decreased after MIIT and HIIT (p ≤ 0.01), and the difference between MIIT and HIIT was not significant (p = 0.09). RPE significantly decreased after HIIT greater than MIIT (p ≤ 0.05). Conclusion Interval training can increase fat oxidation with no effect of exercise intensity, but BLa and RPE decreased after HIIT to greater extent than MIIT.
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Interval training at V??O2max: effects on aerobic performance and overtraining markers
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  • Jan 1999
Purpose: Between inefficient training and overtraining, an appropriate training stimulus (in terms of intensity and duration) has to be determined in accordance with individual capacities. Interval training at the minimal velocity associated with VO 2max (vVO 2max ) allows an athlete to run for as long as possible at VO 2max . Nevertheless, we don't know the influence of a defined increase in training volume at vVO 2max on aerobic performance, noradrenaline, and heart rate. Methods: Eight subjects performed 4 wk of normal training (NT) with one session per week at vVO 2max , i.e., five repetitions run at 50% of the time limit at vVO 2max , with recovery of the same duration at 60% vVO 2max , They then performed 4 wk of overload training (OT) with three interval training sessions at vVO 2max . Results: Normal training significantly improved their velocity associated with VO 2max (20.5 ± 0.7 vs 21.1 ± 0.8 km.h - 1 , P = 0.02). As a result of improved running economy (50.6 ± 3.5 vs 47.5 ± 2.4 mL.min -1 .kg -1 . P = 0.02), VO 2max was not significantly different (71.6 ± 4.8 vs 72.7 ± 4.8 mL.min -1 .kg -1 ). Time to exhaustion at vVO 2max ). was not significantly different (301 ± 56 vs 283 ± 41 s) as was performance (i.e., distance limit run at vVO 2max : 2052.2 ± 331 vs 1986.2 ± 252.9 m). Heart rate at 14 km.h - decreased significantly after NT (162 ± 16 vs 155 ± 18 bpm. P < 0.01). Lactate threshold remained the same after normal training (84.1 ± 4.8% vVO 2max ). Overload training changed neither the performance nor the factors concerning performance. However, the submaximal heart rate measured at 14 kmh -1 decreased after overload training (155 ± 18 vs 150 ± 15 bpm). The maximal heart rate was not significantly different after NT and OT (199 ± 9.5, 198 ± 11, 194 ± 10.4, P = 0.1 Resting plasma norepinephrine (veinous blood sample measured by high pressure liquid chromatography), was unchanged (2.6 vs 2.4 nm.L - 1 , P = 0.8). However, plasma norepinephrine measured at the end of the vVO 2max test increased significantly (11. 1 vs 26.0 nm.L - 1 , P = 0.002). Conclusion: Performance and aerobic factors associated with the performance were not altered by the 4 wk of intensive training at vVO 2max despite the increase of plasma noradrenaline.
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Effects of high vs. Moderate exercise intensity during interval training on lipids and adiponectin levels in obese young females
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We investigate the effects of 12-week interval training of moderate- or high-intensity exercise on blood lipids and plasma levels of adiponectin. Thirty-four obese adolescent females [age = 15.9 ± 0.3 years; BMI and BMI-Z-score = 30.8 ± 1.6 kg/m(2) and 3 ± 0.3, respectively], were randomized to high-intensity interval training (HIIT, n = 11), moderate-intensity interval training (MIIT, n = 11), or a control group (CG, n = 12). Maximal oxygen uptake ([Formula: see text]), maximal aerobic speed (MAS), plasma lipids and adiponectin levels were measured in all subjects before and after training. Following the training program, in both training groups, body mass, BMI-Z-score, and percentage body fat (% BF) decreased, while [Formula: see text] and MAS increased. Low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and adiponectin levels were positively altered (-12.6 and -7.4 %; 6.3 and 8.0 %; 35.8 and 16.2 %; high to moderate training program, respectively). Waist circumference, triglyceride and total cholesterol decreased only in HIIT group (-3.5; -5.3 and -7.0 %, respectively, in all P < 0.05). Significant decrease in the usual index of insulin resistance (HOMA-IR) occurred in HIIT and MIIT groups (-29.2 ± 5.3 and -18.4 ± 8.6 %, respectively; P < 0.01). The results show that HIIT positively changes blood lipids and adiponectin variables in obese adolescent girls, resulting in improved insulin sensitivity, as attested by a lower HOMA-IR, and achieving better results compared to moderate-intensity exercise.
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Intermittent runs at the velocity associated with maximal oxygen uptake enables subjects to remain at maximal oxygen uptake for a longer time than intense but submaximal runs
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  • Feb 2000
Interval training consisting of brief high intensity repetitive runs (30 s) alternating with periods of complete rest (30 s) has been reported to be efficient in improving maximal oxygen uptake (V˙O2max) and to be tolerated well even by untrained persons. However, these studies have not investigated the effects of the time spent at V˙O2max which could be an indicator of the benefit of training. It has been reported that periods of continuous running at a velocity intermediate between that of the lactate threshold (v LT) and that associated with V˙O2max (v V˙ O2max ) can allow subjects to reach V˙O2max due to an additional slow component of oxygen uptake. Therefore, the purpose of this study was to compare the times spent at V˙O2max during an interval training programme and during continuous strenuous runs. Eight long-distance runners took part in three maximal tests on a synthetic track (400 m) whilst breathing through a portable, telemetric metabolic analyser: they comprised firstly, an incremental test which determined v LT, V˙O2max [59.8 (SD 5.4) ml · min−1 · kg−1], v V˙ O2max [18.5 (SD 1.2) km · h−1], secondly, an interval training protocol consisting of alternately running at 100% and at 50% of v V˙ O2max (30 s each); and thirdly, a continuous high intensity run at v LT + 50% of the difference between v LT and v V˙ O2max [i.e. v Δ50: 16.9 (SD 1.00) km · h−1 and 91.3 (SD 1.6)% v V˙ O2max ]. The first and third tests were performed in random order and at 2-day intervals. In each case the subjects warmed-up for 15 min at 50% of v V˙ O2max . The results showed that in more than half of the cases the v Δ50 run allowed the subjects to reach V˙O2max, but the time spent specifically at V˙O2max was much less than that during the alternating low/high intensity exercise protocol [2 min 42 s (SD 3 min 09 s) for v Δ50 run vs 7 min 51 s (SD 6 min 38 s) in 19 (SD 5) interval runs]. The blood lactate responses were less pronounced in the interval runs than for the v Δ50 runs, but not significantly so [6.8 (SD 2.2) mmol · l−1 vs 7.5 (SD 2.1) mmol · l−1]. These results do not allow us to speculate as to the chronic effects of these two types of training at V˙O2max.
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High-intensity intermittent training versus moderate-intensity intermittent training: Is it a matter of intensity or intermittent efforts?
Article
  • Jan 2017
High-intensity intermittent training (HIIT) has gained popularity in recent years for its similar or higher effects compared with aerobic continuous training (ACT) or controls in different age groups, several health-related parameters and cardiovascular diseases (CVD)1–3 as well as in competitive athletes. To analyse the role of HIIT comparing HIIT group with controls is an adequate approach for describing acute or chronic responses to a particular training model. However, when aiming to compare the efficacy of two training regimens, it has been usual to compare HIIT with ACT.1 In those cases, authors explained the differences largely on the grounds of intensity.4 However, we highlight that these studies compared two training modalities which are different in their training intensity and in the stimulus type—intermittent versus continuous. To the best of our knowledge, only three studies5–7 analysed the influence of intensity itself—by comparing HIIT and moderate-intensity intermittent training (MIIT). Alkahtani et al 5 examined the effect of 4-week MIIT and HIIT on fat oxidation and the responses …
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The impact of work-matched interval training on VO2peak and VO2 kinetics: Diminishing returns with increasing intensity
Article
  • Feb 2016
High intensity interval training (HIIT) improves VO2peak and VO2 kinetics, however, it is unknown whether an optimal intensity of HIIT exists for eliciting improvements in these measures of whole body oxidative metabolism. The purpose of this study was to: 1) investigate the effect of interval intensity on training-induced adaptations in VO2peak and VO2 kinetics, and 2) examine the impact of interval intensity on the frequency of nonresponders in VO2peak. 36 healthy men and women completed 3 weeks of cycle ergometer HIIT, consisting of intervals targeting 80% (LO), 115% (MID) or 150% (HI) of peak aerobic power. Total work performed per training session was matched across groups. A main effect of training (p < 0.05), and a significant interaction effect was observed for VO2peak, with the change in VO2peak being greater (p < 0.05) in the MID group than the LO group; however, no differences were observed between the HI group and either the MID or LO groups (DVO2peak; LO, 2.7 ± 0.7 ml/kg/min; MID, 5.8 ± 0.7; HI, 4.2 ± 1.0). The greatest proportion of responders was observed in the MID group (LO, 8/12; MID, 12/13; HI, 9/11). A non-significant relationship (p = 0.26; r2 = 0.04) was found between the changes in VO2peak and τVO2. These results suggest that training at intensities around VO2peak may represent a threshold intensity above which further increases in training intensity provide no additional adaptive benefit. The dissociation between changes in VO2peak and VO2 kinetics also reflects the different underlying mechanisms regulating these adaptations.
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