Months Of High-intensity Interval Training Research Articles

Effects of 8 months of high-intensity interval training on physical fitness and health-related quality of life in substance use disorder.

This study aimed to investigate the effect of 8 months of high-intensity interval training (HIIT) on physical fitness and health-related quality of life in substance use disorder. Sixty substance use disorder were randomly assigned to either the HIIT group or the control group according to a random sampling method. The HIIT group received 8 months of four 60-min sessions per week under supervision. Weight, waist circumference, body fat percentage, heart rate, blood pressure, VO2max, reaction time, grip strength, standing on one foot with eyes closed, sitting forward flexion, and quadrant jumping, standing on one foot with eyes closed, the number of push-ups, quality of life (SF-36) score, and craving (VAS) scored were monitored in the HIIT and control groups at baseline, 4 months, and 8 months. SPSS 22.0 was used to conduct repeated measurement analysis of variance and Pearson correlation analysis on the collected subject data. Compared with baseline, weight (p < 0.001), waist circumference (p < 0.001), body fat percentage (p < 0.001), heart rate (p < 0.05), Systolic blood pressure (p < 0.01), systolic blood pressure (p < 0.05), reaction time (p < 0.001),PSQI (p < 0.001), Total cholesterol (p < 0.001), Triglyceride (p < 0.001), Blood sugar (p < 0.001) and VAS score (p < 0.001) were significantly decreased after 8 months of exercise intervention. Contrastingly, VO2max (p < 0.05), grip strength (p < 0.05), eyes closed and one foot Standing (p < 0.001), sitting forward flexion (p < 0.001), quadrant jumping (p < 0.001), push-ups (p < 0.001), PCS (p < 0.001), and MCS (p < 0.001) were significantly increased. VO2max was significantly negatively correlated with VAS (r = -0.434, p < 0.001), and significantly positively correlated with PCS (r = 0.425, p < 0.001). There was a positive correlation between standing on one foot with closed eyes and MCS (r = 0.283, p < 0.05). Eight months of HIIT can comprehensively improve the physical health level and health-related quality of life of men with substance use disorders, reduce the desire for drugs, and lay the foundation for better starting a happy life.

Effect of Training on Vascular Function and Repair in Heart Failure With Preserved Ejection Fraction

BackgroundExercise training improves peak oxygen uptake (V.O2peak) in heart failure with preserved ejection fraction (HFpEF). Multiple adaptations have been addressed, but the role of circulating endothelium-repairing cells and vascular function have not been well defined. ObjectivesThe authors investigated effects of moderate-intensity continuous training (MICT) and high-intensity interval training (HIIT) on vascular function and repair in HFpEF. MethodsThis study is a subanalysis of the OptimEx-Clin (Optimizing Exercise Training in Prevention and Treatment of Diastolic Heart Failure) study randomizing patients with HFpEF (n = 180) to HIIT, MICT, or guideline control. At baseline, 3, and 12 months, the authors measured peripheral arterial tonometry (valid baseline measurement in n = 109), flow-mediated dilation (n = 59), augmentation index (n = 94), and flow cytometry (n = 136) for endothelial progenitor cells and angiogenic T cells. Abnormal values were defined as outside 90% of published sex-specific reference values. ResultsAt baseline, abnormal values (%) were observed for augmentation index in 66%, peripheral arterial tonometry in 17%, flow-mediated dilation in 25%, endothelial progenitor cells in 42%, and angiogenic T cells in 18%. These parameters did not change significantly after 3 or 12 months of HIIT or MICT. Results remained unchanged when confining analysis to patients with high adherence to training. ConclusionsIn patients with HFpEF, high augmentation index was common, but endothelial function and levels of endothelium-repairing cells were normal in most patients. Aerobic exercise training did not change vascular function or cellular endothelial repair. Improved vascular function did not significantly contribute to the V.O2peak improvement after different training intensities in HFpEF, contrary to previous studies in heart failure with reduced ejection fraction and coronary artery disease. (Optimizing Exercise Training in Prevention and Treatment of Diastolic Heart Failure [OptimEx-Clin]; NCT02078947)

CENIT (Impact of Cardiac Exercise Training on Lipid Content in Coronary Atheromatous Plaques Evaluated by Near-Infrared Spectroscopy): A Randomized Trial.

BackgroundThe effect of physical exercise on lipid content of coronary artery plaques is unknown. With near infrared spectroscopy we measured the effect of high intensity interval training (HIIT) on lipid content in coronary plaques in patients with stable coronary artery disease following percutaneous coronary intervention.Methods and ResultsIn CENIT (Impact of Cardiac Exercise Training on Lipid Content in Coronary Atheromatous Plaques Evaluated by Near‐Infrared Spectroscopy) 60 patients were randomized to 6 months supervised HIIT or to a control group. The primary end point was change in lipid content measured as maximum lipid core burden index at 4 mm (maxLCBI4mm). A predefined cutoff of maxLCBI4mm >100 was required for inclusion in the analysis. Forty‐nine patients (HIIT=20, usual care=29) had maxLCBI4mm >100 at baseline. Change in maxLCBI4mm did not differ between groups (−1.2, 95% CI, −65.8 to 63.4, P=0.97). The estimated reduction in maxLCBI4mm was −47.7 (95% CI, −100.3 to 5.0, P=0.075) and −46.5 (95% CI, −87.5 to −5.4, P=0.027) after HIIT and in controls, respectively. A negative correlation was observed between change in peak oxygen uptake (VO2peak) and change in lipid content (Spearman’s correlation −0.44, P=0.009). With an increase in VO2peak above 1 metabolic equivalent task, maxLCBI4mm was on average reduced by 142 (−8 to −262), whereas the change was −3.2 (154 to −255) with increased VO2peak below 1 metabolic equivalent task.ConclusionsSix months of HIIT following percutaneous coronary intervention did not reduce lipid content in coronary plaques compared with usual care. A moderate negative correlation between increase in VO2peak and change in lipid content generates the hypothesis that exercise with a subsequent increase in fitness may reduce lipid content in coronary atheromatous plaques.RegistrationURL: https://www.clinicaltrials.gov; Unique identifier: NCT02494947.

A randomized clinical study evaluating effects of high-intensity interval training on myocardial microvascular dysfunction

Abstract Background Myocardial microvascular function assessed with the Index of Microcirculatory Resistance (IMR) after heart transplantation (HTx) predicts the development of cardiac allograft vasculopathy (CAV) and adverse long-term outcome. This study aimed to evaluate the otherwise beneficial effects of high-intensity interval training (HIT) on microvascular dysfunction development. Methods Eighty-one de novo HTx patients were randomized to nine consecutive months of HIT or standard care rehabilitation. Coronary physiology assessment with a pressure wire was performed in the left anterior descending coronary artery. IMR was calculated by multiplying the mean distal coronary pressure by the mean hyperemic transit time. Results obtained at three and twelve months after HTx were compared to assess the treatment effect of HIT. Results Results were available for 60 patients. 71% were men, and the mean age was 48±13. IMR in the HIT group (n=26) decreased from 14.8±9.5 to 13.8±8.0, change = 1.2, 95% CI [−2.6 to 4.9] and increased in the standard care group (n=34) from 13.8±5.8 to 16.8±12.0, change = −3.5, 95% CI [−7.1 to 0.1]. The mean difference between groups was 4.7, 95% CI [−9.7 to 0.4], p=0.07. Conclusion These results suggest that early initiation of HIT improves microvascular function. Funding Acknowledgement Type of funding sources: Foundation. Main funding source(s): Stiftelsen Dam

Effects of antihypertensive medication and high‐intensity interval training in hypertensive metabolic syndrome individuals

Pharmacological and non-pharmacological therapies are simultaneously prescribed when treating hypertensive individuals with elevated cardiovascular risk (ie, metabolic syndrome individuals). However, it is unknown if the interactions between antihypertensive medication (AHM) and lifestyle interventions (ie, exercise training) may result in a better ambulatory blood pressure (ABP) control. To test this hypothesis, 36 hypertensive individuals with metabolic syndrome (MetS) under long-term prescription with AHM targeting the renin-angiotensin-aldosterone system (RAAS) were recruited. Before and after 4months of high-intensity interval training (HIIT), participants completed two trials in a double-blind, randomized order: (a) placebo trial consisting of AHM withdrawal for 3days and (b) AHM trial where individuals held their habitual dose of AHM. In each trial, 24-h mean arterial pressure (MAP) was monitored and considered the primary study outcome. Secondary outcomes included plasma renin activity (PRA) and aldosterone concentration to confirm withdrawal effects on RAAS, along with the analysis of urine albumin-to-creatinine ratio (UACR) to assess kidney function. The results showed main effects from AHM and HIIT reducing 24-h MAP (-5.7mmHg, p<0.001 and -2.3mmHg, p=0.007, respectively). However, there was not interaction between AHM and HIIT on 24-h MAP (p=0.240). There was a main effect of AHM increasing PRA (p<0.001) but no effect on plasma aldosterone concentration (p= 0.368). HIIT did not significantly improve RAAS hormones or the UACR. In conclusion, AHM and HIIT have independent and additive effects in lowering ABP. These findings support the combination of habitual AHM with exercise training with the goal to reduce ABP in hypertensive MetS individuals.

Feasibility and effects of high-intensity interval training in older adults living with HIV

ABSTRACT Adults with HIV on therapy can live a normal lifespan but exhibit advanced ageing which includes reduced cardiorespiratory fitness. Our objective was to determine the feasibility and effects of high-intensity interval training (HIIT) combined with resistance training (RT) in older adults with HIV. We conducted a cross-over pilot study within a randomized exercise trial in sedentary adults with HIV ≥50 years of age. First, participants were randomized to 4 months of continuous high-intensity aerobic exercise (AEX) and RT 3x/week or standard of care control. Then, the control group completed 4 months of HIIT + RT (3x/week). Among the 32 individuals enrolled, 26 eligible participants were randomized. Most participants were African American (63%) and male (95%) with a mean (SD) age of 61.5 (6.7) years and VO2peak of 24.5 (4.9) ml/kg/min. Attendance and adherence to both exercise training interventions were high. The clinically significant increases in VO2peak (ml/kg/min) after HIIT (3.09 ±1.04, p=0.02) and AEX (2.09 ±0.72, p=0.01) represented improvements of 17.1% and 7.7%, respectively. Both groups had improvements in exercise endurance (time on the treadmill) and strength (all p< 0.01). This pilot study supports HIIT as an efficient means to deliver high-intensity AEX to improve cardiorespiratory fitness toward the goal of attenuating the accelerated ageing process in adults with HIV.

Long-term effects of high-intensity training vs moderate intensity training in heart transplant recipients: A 3-year follow-up study of the randomized-controlled HITTS study.

The randomized controlled High-Intensity Interval Training in De Novo Heart Transplant Recipients in Scandinavia (HITTS) study compared 9months of high-intensity interval training (HIT) with moderate intensity continuous training in de novo heart transplant recipients. In our 3-year follow-up study, we aimed to determine whether the effect of early initiation of HIT on peak oxygen consumption (VO2peak ) persisted for 2years postintervention. The study's primary end point was the change in VO2peak (mL/kg/min). The secondary end points were muscle strength, body composition, heart rate response, health-related quality of life, daily physical activity, biomarkers, and heart function. Of 78 patients who completed the 1-year HITTS trial, 65 entered our study and 62 completed the study tests. VO2peak increased from baseline to 1year and leveled off thereafter. During the intervention period, the increase in VO2peak was larger in the HIT arm; however, 2years later, there was no significant between-group difference in VO2peak . However, the mean change in the anaerobic threshold and extensor muscle endurance remained significantly higher in the HIT group. Early initiation of HIT after heart transplantation appears to have some sustainable long-term effects. Clinical trial registration number: NCT01796379.

Effect of High-Intensity Interval Training in De Novo Heart Transplant Recipients - 3-year Results from the HITTS Randomized Controlled Trial

The HITTS study (High -intensity Interval Training in de novo Heart Transplant Recipients in Scandinavia) is a randomized controlled trial designed to assess the effect of high-intensity interval training (HIT) versus moderate intensity continuous training (MICT) on exercise capacity in de novo heart transplant recipients. The primary endpoint was the change in oxygen consumption (VO2peak) at the end of the intervention period, which began 3 months after heart transplantation (HTx). After the 9-month long intervention period, we reported a between-group difference in VO2peak of 1.8 ml/kg/min in favor of HIT (p = 0.04).We found that HIT was safe, well tolerated and efficient. The HITTS study is the first randomized controlled trial to assess the effectiveness of HIT in de novo heart transplant recipients. However, long-term effects of commencing HIT soon after HTx remain unknown. In this extension of the HITTS trial, our aim was to examine whether the benefits of 9 months of supervised HIT training persist two years after the end of the intervention. In the HITTS study, we randomized 81 adult de novo heart transplant recipients to 9 months of HIT (4 × 4 min intervals at 85-95% of peak heart rate (HR) or 9 months of MICT (60-80% of peak HR). The mean ± SD age was 49 ±13 and 73 % were men. Before the start of the intervention and at follow-up shortly after the intervention, we measured VO2peak, isokinetic muscle strength, body composition, left ventricular function by echo, biomarkers, and health-related quality of life (HRQoL). For the extension study, the measurements will be repeated 3 years after enrollment. VO2peak is measured with breath-by-breath gas exchange on a treadmill or bicycle ergometer. The last patient is scheduled to complete his/her 3-year follow-up at Nov 14th, 2019. Data will be available for presentation at ISHLT 2020. The primary outcome is the long-term effect of HIT vs MICT on aerobic exercise capacity as assessed by VO2peak. Secondary outcomes are: Isokinetic muscular strength in the lower limbs by a dynamometer, body composition (bio-impedance analysis), left ventricular function by echo, heart rate response during the cardiopulmonary exercise test, relevant circulation biomarkers (renal function, NT-proBNP and cardiac troponins), HRQoL, tolerability, safety and adverse events.

Benefits of High-Intensity Interval Training in a Young and in an Older De Novo Heart Transplant Recipient- Cases from the HITTS Study

High-intensity interval training (HIT) is an effective method to increase exercise capacity in de novo heart transplant recipients, as shown in the recently published HITTS study (High-intensity Interval Training in de novo Heart Transplant recipients in Scandinavia). We were interested to scrutinize the potential effect of HIT in different age categories. The main effects of HIT in one young and one older medically stable de novo heart transplant recipients are reported. The HITTS study is a randomized controlled study comparing HIT versus moderate intensity continuous training (MICT) in de novo heart transplant recipients (mean 11 weeks after heart transplantation). Eighty-one participants were randomized (1:1) to 9 months of HIT or MICT. The primary endpoint was the change in VO2peak. Secondary endpoints included: Heart rate response, muscle strength and self-reported physical function measured by the Short-Form-36. One of the youngest and one of the oldest participants with the highest changes in VO2peak in the HIT intervention group were selected for this case report. The youngest male (< 25 years old) increased his VO2peak with 15.3 mL/kg/min from baseline to follow-up (from 23.5 to 38.8 mL/kg/min), while the older male (> 55 years old) increased his VO2peak with 12.6 mL/kg/min (from 15.6 to 28.3 mL/kg/min). Muscle strength, heart rate response, O2 pulse and self-reported physical function also increased substantially (Table). The young heart transplant recipient completed 51 exercise sessions whereas the older heart transplant recipient completed 72 sessions. Both the young and the older de novo heart transplant recipient increased their VO2peak with at least 4 METS (> 12 mL/kg/min) after a 9-month long HIT intervention. The results show that both young and older individuals can derive substantial benefit from HIT soon after heart transplantation.

HIIT Improves Left Ventricular Exercise Response in Adults with Type 2 Diabetes.

This study aimed to determine whether 3 months of high-intensity interval training (HIIT) improves left ventricular function during exercise in adults with type 2 diabetes. Participants performed a V˙O2peak test and received a DXA scan and total blood volume measurement at baseline. Left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV), and left ventricular stroke volume (LVSV) were then measured at rest and during low- and moderate-intensity semirecumbent exercise in adults with type 2 diabetes before and after 3 months of HIIT (n = 11) or no training (control) (n = 5). The effects of HIIT were determined using repeated-measures ANOVA. HIIT increased V˙O2peak by approximately 15% (P < 0.002) but did not change body composition or total blood volume. LVESV decreased and LVEDV and LVSV increased from rest to moderate-intensity exercise in both groups at baseline (all P < 0.01). Three months of HIIT increased LVEDV (P = 0.008) and LVSV (P = 0.02) at all conditions, but there was no difference in controls (all P > 0.05). HIIT augmented the reduction in LVESV from rest to moderate-intensity exercise (P < 0.04), but LVESV was unchanged in controls. Increased LVEDV explained 51% of the change in LVSV after HIIT intervention. Mitral inflow parameters and mitral annular velocities were unaffected by HIIT (all P > 0.05). HIIT training increased the LVSV response to exercise in adults with type 2 diabetes. These data suggest that HIIT can improve LV filling and emptying during exercise and reverse early cardiac consequences of type 2 diabetes.

High-intensity interval training in cardiac resynchronization therapy: a randomized control trial.

To determine the effects of high-intensity interval training (HIIT) following cardiac resynchronization therapy (CRT) implantation in patients with chronic heart failure (CHF), on noninvasive estimates of systolic ventricular function, exercise performance, severity of symptoms and quality of life. Cardiopulmonary exercise testing, resting transthoracic echocardiogram and health-related quality of life assessment were obtained before and at 6months after CRT implantation in 37 patients with moderate-to-severe CHF. Patients were randomized after CRT to either a 24-week HIIT group (90-95% peak heart rate, 2days per week) or to a usual care group (CON). Mixed design 2×2 repeated measures ANOVA were used to test for differences within and in-between groups. Improvements in health-related quality of life (HIIT = 98.54%, CON = 123.47%), NYHA class (HIIT = 43.44%, CON = 38.30%) HR recovery at minute 1 (HIIT = 32.32%, CON = 42.94%), pulse pressure at peak effort (HIIT = 14.06%, CON = 9.52%, LVEF (HIIT = 42.17%, CON = 51.10%) and LV Mass (HIIT = 13.26%, CON = 11.88%) were similar in both groups (p > 0.05). Significant increases in CPET duration in the HIIT group(25.94%), and increases in peak VO2 (HIIT = 8.64%, CON = 4.85%) and percent-predicted VO2 (HIIT = 10.57%, CON = 4.26%) in both groups, were observed in the intention-to-treat analysis. Six months of HIIT in patients in CRT did not further improved indices of functional capacity and health-related quality of life, and LV structure and function, compared to CRT alone. However, HIIT led to further improvements in exercise performance. It remains unclear whether HIIT benefits patients in CRT to a similar degree as more conventional forms of exercise training previously shown to maximize benefits in CRT. http://www.clinicaltrials.gov . Unique identifier: NCT02413151.

Effect of High-Intensity Interval Training on Progression of Coronary Artery Vasculopathy in De Novo Heart Transplant Recipients

Purpose Coronary artery vasculopathy (CAV) leads to increased morbidity and mortality in heart transplant (HTx) recipients. We have previously shown that high-intensity interval training (HIT) in maintenance recipients significantly reduced CAV progression, as compared to a control group. Our hypothesis was that HIT compared to moderate intensity, continuous training (MICT) in de novo HTx recipients would show similar results. Methods 67 HTx recipients (mean ± SD age 49 ± 13, 72 (% men) were randomized to either nine months of HIT or MICT at mean 11 weeks (range 7 - 16) post HTx. The effect of training on CAV progression was assessed by matched intravascular ultrasound (IVUS) examinations at baseline and 12 months, and analyses were performed to measure change in Maximal Intimal Thickness (MIT), Percent Atheroma Volume (PAV) and Total Atheroma Volume (TAV). Results Age and sex were similar between the groups. Peak oxygen consumption (VO2peak L/min) improved with 12.5 ± 10.3 % in the HIT group vs. 8.7 ± 9.3 % in the MICT group (p=0.022). IVUS analysis revealed a relatively small increase in all the three main IVUS parameters in both groups: The mean ± SD increase in MIT was 0.08 ± 0.12mm in the HIT group vs. 0.06 ± 0.10 mm in the MICT group. The increase in PAV was 4.3 ± 5.6 % in the HIT group vs. 3.2 ± 3.9 % in the MICT group, and TAV increased with 20.0 ± 51.5 mm3in the HIT group vs. 25.7 ± 44.8mm3 in the MICT group, but there were no significant differences between the groups (see Table 1). Furthermore, there were no significant correlations between VO2peak and MIT, PAV or TAV in either of the groups. Conclusion The increase in VO2 peak was significantly greater in HIT patients as compared to the MICT group. However, there was no significant difference in progression of CAV between the two treatment groups. We await the results from the 3-year follow-up to evaluate potential long-term effects.

Body composition and insulin sensitivity after high‐intensity interval training in overweight/obese patients

TO THE EDITOR: We have read with a great interest the article of Gillen et al. (1) recently published in Obesity on the shortterm effects of high-intensity interval training (HIIT) in obese women. They reported similar skeletal muscle adaptations (increased mitochondrial capacity) and similar (but modest) body composition improvement after short-term HIIT (6 weeks) in fasted or fed state obese women. Surprisingly, insulin sensitivity was not improved after 6 week of HIIT in both groups probably due to potential influence of patient’s diet (not reported in the article) and/or short-term training period. We would like to underlie the importance of patient’s diet and nutritional aspects (with exercise intervention) for body composition and insulin sensitivity improvements in obese population. Previous studies demonstrated that HIIT combined with Mediterranean diet (diet focused on nutrient quality, satiety, and palatability) optimally improved body composition and insulin sensitivity in obese patients (2-5). Those studies have found an improved body composition after shorter and longer term HIIT combined with Mediterranean diet (2-5), as well as an improved insulin sensitivity in obese patients (4,5). We have also developed an optimized, time efficient model of HIIT in obese patients (2,3,5), and HIIT combined with Mediterranean diet have superior effects on body composition and insulin sensitivity improvement compared to moderate intensity continuous exercise (3) or mediterranean diet alone (4). As the authors stated (1), compared to sprint interval training, HIIT is more adapted to obese population that often present comorbidities and low levels of fitness. We demonstrated that two 10-min sets of repeated bouts of 15-30 s at 80% of maximal aerobic power interspersed by 15-30 s passive recovery periods (representing 10 min of real exercise), 2-3 time/week are enough to improve body composition, insulin sensitivity, and cardiometabolic risk factors in obese patients. Regarding potential sex differences adaptations to HIIT, we showed similar improvement in body composition, fitness, and cardiometabolic risk factors in obese men and women (metabolically healthy or not) after 9 months of HIIT combined with Mediterranean diet (5). Similarly, we found that insulin sensitivity was similarly improved after the same intervention in obese men and women (Figure 1). In conclusion, intensive exercise intervention such as HIIT combined with Mediterranean diet can optimize health benefits (body composition, insulin sensitivity, and cardiometabolic risk factors) in obese patients, independently of their gender and/or obesity phenotype. O