Adherence, Compliance Rates, and Response to Training Among Patients Awaiting Colorectal Cancer Surgery: A Secondary Analysis From the PREHAB Multicentre Trial.

BackgroundStudies have shown that high-intensity interval training (HIIT) is superior to moderate-intensity continuous training (MICT) for increasing peak oxygen uptake (VO2peak) and reducing cardiovascular disease (CVD) and mortality. To our knowledge, previously published systematic reviews have neither compared different HIIT models with MICT nor investigated intervention frequencies of HIIT vs. MICT for purposes of improving cardiorespiratory fitness in patients with CVD.ObjectiveThe purpose of this meta-analysis was to compare the effects of different training models, intervention frequencies and weeks of HIIT vs. MICT on changes in cardiorespiratory fitness during cardiac rehabilitation (CR).MethodsA systematic search was carried out for research articles on randomized controlled trials (RCTs) indexed in the PubMed, Cochrane Library, Web of Science, Embase and Scopus databases for the period up to December 2021. We searched for RCTs that compared the effect of HIIT vs. MICT on cardiorespiratory fitness in patients with CVD.ResultsTwenty-two studies with 949 participants (HIIT: 476, MICT: 473) met the inclusion criteria. Sensitivity analysis revealed that HIIT increased VO2peak more than MICT (MD = 1.35). In the training models and durations, there was a greater increase in VO2peak with medium-interval HIIT (MD = 4.02) and more than 12 weeks duration (MD = 2.35) than with MICT. There were significant improvements in VO2peak with a HIIT frequency of 3 times/week (MD = 1.28). Overall, one minor cardiovascular and four non-cardiovascular adverse events were reported in the HIIT group, while six non-cardiovascular adverse events were reported in the MICT group.ConclusionHIIT is safe and appears to be more effective than MICT for improving cardiorespiratory fitness in patients with CVD. Medium-interval HIIT 3 times/week for more than 12 weeks resulted in the largest improvement in cardiorespiratory fitness during CR.Systematic Review Registrationhttps://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021245810, identifier: CRD42021245810.

Introduction: Laboratory-based High intensity interval training (HIIT) is an efficacious time-saving exercise modality resulting in similar adaptations to traditional moderate-intensity continuous training. Recently, Home-based HIIT, involving bodyweight exercises, has gained popularity in the literature, as it overcomes additional barriers such as limited access to facilities and appropriate equipment. However, literature in to home-based HIIT is still sparse, and little is known about how manipulating interval duration, interval number and work-to-rest ratio could influence the efficacy and effectiveness of such interventions. Aims: Two separate but related studies were conducted. The aim of study 1 was to investigate the acute physiological, perceptual, and motivational responses to five home-based HIIT protocols with various work-to-rest ratios (specifically 1:1, 1:2 and 1:4) and interval durations (30s or 60s). The aim of study 2 was to implement and compare two of the HIIT protocols investigated in study one to identify the ideal interval duration for improving cardiorespiratory fitness (CRF) and health in sedentary individuals. Methods: In Study 1, 10 healthy participants (age = 25±4 yrs, BMI = 22.7±1.4kg.m2) completed a randomised cross-over study, whereby each participant completed five bodyweight HIIT protocols, four using 30s intervals (30:30x6 (30s interval interspersed with 30s rest, completed 6 times), 30:60x6, 30:120x6 and 30:30x12) and one using 60s intervals (60:60x6). A total of 12 exercises were implemented, examples included burpees, mountain climbers, and jumping jacks. Blood lactate, heart rate (HR), feeling scale (FS), enjoyment and perceived competence were measured in response to each protocol. In Study 2, 28 healthy sedentary participants (age = 29±10 yrs, BMI = 25.3±3.9 kg.m2) completed a randomised cross-over design, whereby each participant completed 6 weeks of 30:120HIIT (4-8x30s with 120s rest) and 60:60HIIT (6-10x60s with 60s rest). In addition to the 12 exercises implemented in study 1, a further 6 were added in study 2. CRF, body composition (bioimpedance), blood pressure and aortic pulse wave velocity were assessed pre and post each intervention, with a 4-6-week wash-out period between interventions. Results: Study 1 (acute phase), established that 60:60x6 and 30:30x12 resulted in significantly higher change in blood lactate and HR responses compared to 30:30x6, 30:60x6, and 30:120x6 (P<0.05). 30:120x6 had a significantly higher minimum reported feeling scale score compared to all other protocols (P<0.05). No significant differences were reported for interest/enjoyment or perceived competence between protocols (P>0.05). Study 2 (chronic phase) demonstrated that CRF increased following both 30:120HIIT and 60:60HIIT (P<0.05). There was a significant reduction in aPWV following 30:120HIIT and 60:60HIIT (P<0.05). Systolic BP decreased significantly in 30:120HIIT with no difference in 60:60HIIT (P=0.414). Magnitude of change between protocols was not different for any of the measured variables (P>0.05). Conclusion: This is the first study to directly compare different home-based HIIT protocols by manipulating interval durations and work-to-rest ratios. Home-based HIIT protocols consisting of 30:120HIIT and 60:60HIIT improved CRF and aPWV after 6 weeks in sedentary individuals, despite 30:120HIIT producing significantly lower lactate and heart rate responses whilst also showing less aversive perceptions during an acute bout of exercise to that of 60:60HIIT.

ObjectiveHigh‐intensity interval training (HIIT) has been shown to be more effective than moderate continuous aerobic exercise for improving cardiorespiratory fitness (CRF) in a limited time frame. However, the length of time required for HIIT to elicit clinically significant improvements in the CRF of older adults is currently unknown. The aim of this study was to compare changes in the CRF of older adults completing identical HIIT protocols of varying durations.MethodsForty healthy, community‐dwelling older adults completed a cardiopulmonary exercise test (CPET) before and after 2, 4, or 6 weeks of fully supervised HIIT on a cycle ergometer, or a no‐intervention control period.ResultsAnaerobic threshold (AT) was increased only after 4 (+1.9 [SD 1.1] mL/kg/min) and 6 weeks (+1.9 [SD 1.8] mL/kg/min) of HIIT (both P < 0.001), with 6‐week HIIT required to elicit improvements in VO2 peak (+3.0 [SD 6] mL/kg/min; P = 0.04). Exercise tolerance increased after 2 (+15 [SD 15] W), 4 (+17 [SD 11] W), and 6 weeks (+16 [SD 11] W) of HIIT (all P < 0.001), with no difference in increase between the groups. There were no changes in any parameter in the control group.ConclusionImprovements in exercise tolerance from HIIT precede changes in CRF. Just 4 weeks of a well‐tolerated, reduced‐exertion HIIT protocol are required to produce significant changes in AT, with a further 2 weeks of training also eliciting improvements in VO2 peak.

Purpose: To compare the effects of 8 weeks of two types of interval training, Sprint Interval Training (SIT) and High-Intensity Interval Training (HIIT), on anthropometric measures and cardiorespiratory fitness in healthy young women.Methods: A randomized clinical trial in which 49 young active women [age, 30.4 ± 6.1 years; body mass index, 24.8 ± 3.1 kg.m−2; peak oxygen consumption (VO2peak), 34.9±7.5 mL.kg−1.min−1] were randomly allocated into a SIT or HIIT group. The SIT group performed four bouts of 30 s all-out cycling efforts interspersed with 4 min of recovery (passive or light cycling with no load). The HIIT group performed four bouts of 4-min efforts at 90–95% of peak heart rate (HRpeak) interspersed with 3 min of active recovery at 50–60% of HRpeak. At baseline and after 8 weeks of intervention, waist circumference, skinfolds (triceps, subscapular, suprailiac, abdominal, and thigh), body mass and BMI were measured by standard procedures and cardiorespiratory fitness was assessed by cardiorespiratory graded exertion test on an electromagnetically braked cycle ergometer.Results: The HIIT and SIT groups improved, respectively, 14.5 ± 22.9% (P < 0.001) and 16.9 ± 23.4% (P < 0.001) in VO2peak after intervention, with no significant difference between groups. Sum of skinfolds reduced 15.8 ± 7.9 and 22.2 ± 6.4 from baseline (P < 0.001) for HIIT and SIT groups, respectively, with greater reduction for SIT compared to HIIT (P < 0.05). There were statistically significant decreases in waist circumference (P < 0.001) for the HIIT (−3.1 ± 1.1%) and SIT (−3.3 ± 1.8%) groups, with no significant difference between groups. Only SIT showed significant reductions in body weight and BMI (p < 0.05).Conclusions: Eight weeks of HIIT and SIT resulted in improvements in anthropometric measures and cardiorespiratory fitness, even in the absence of changes in dietary intake. In addition, the SIT protocol induced greater reductions than the HIIT protocol in the sum of skinfolds. Both protocols appear to be time-efficient interventions, since the HIIT and SIT protocols took 33 and 23 min (16 and 2 min of effective training) per session, respectively.

Low cardiorespiratory fitness (CRF) is an important risk factor for cardiometabolic disease and individuals with prediabetes tend to have low CRF. Trials that have compared High-Intensity Interval Training(HIIT) to Moderate-Intensity Continuous Training(MICT) by imposingindividuals to HIIT or MICT haveestablished that HIIT is effective for improving CRF. However, to maintain these improvements, individuals need to adhere to HIIT. Self-determination theory states that providingchoicehas a positive impact on exercise adherence. PURPOSE:To address whether having the choice to engage in HIITor MICT for 6-months (CHOICE) leads to greater changes in CRF (absolute and relative VO2peak) at 6-months when compared to IMposed HIIT (IM-HIIT)or IMposed MICT (IM-MICT) in adults with prediabetes. METHODS: In this single-site randomized trial, 68 low-active adults (56.8±6.6 yrs, mean±SD) living with prediabetes were randomized to CHOICE (n=24), IM-HIIT (n=21), or IM-MICT (n=23). After an initial supervised training period (6 sessions over 3 weeks) participants exercised unsupervised on their own in free-living conditions for 6 months. A ramp increase cycle ergometer test to exhaustion was conducted by the same technician pre- and post-testing to determine VO2peak. Missing data was accounted for using linear interpolations generated with SPSS®v.20.0. RESULTS: ANCOVA results with baseline CRF as a covariate revealed no significant differences between increases in absolute VO2peak (CHOICE: 0.38, 95% CI; 0.20, 0.55, vs. IM-HIIT: 0.56, 95% CI; 0.37, 0.74 vs. IM-MICT: 0.30, 95% CI; 0.12, 0.48 L/min, F2,64=1.99, P=.14), with similar findings for relative VO2peak (F2,67=0.32, P=.73). Within group changes over time indicated small effect sizes (Hedge’s g) for increases in absolute (CHOICE= 0.00; HIIT = 0.26; and MICT=0.01) and relative VO2peak over time (CHOICE = 0.11; HIIT = 0.33; and MICT=0.15). CONCLUSION:Changes in CRF between groups randomized to perform HIIT or MICT, or given the choice of HIIT or MICT, were not significantly different at 6-months post-intervention. Providing choice for selecting HIIT or MICT did not appear to enhance the benefits of exercise for improving fitness in low active adults. Supported by the Research Endowment from the American College of Sports Medicine Foundation.

This study aims to systematically review the systematic reviews and meta-analyses examining the effect of high-intensity interval training (HIIT) protocols on improving cardiorespiratory fitness (CRF) and to characterize the main patterns of HIIT modalities using clustering statistical procedures to examine their potential differences on improving CRF. Finally, we aimed to develop a comprehensive guideline for reporting HIIT protocols. A systematic review was conducted on PubMed and Web of Science from their inception to 31 October 2022 for systematic reviews and meta-analysis aimed at assessing the effect of HIIT on CRF in the entire study population. The Assessment of Multiple Systematic Reviews 2 tool was used to evaluate the risk of bias of each review. Additionally, a principal component analysis testing the data adequacy for the factor solution through the Kaiser-Meyer-Olkin procedure test was conducted. Once the number of factors was identified, in order to identify data patterns according to the main characteristics of the HIIT protocols, a two-step cluster analysis was conducted. Nineteen systematic reviews and/or meta-analyses comprising 103 studies were included. Clustering of systematic reviews and meta-analyses identified three HIIT modalities ('HIIT-normal mixed', 'HIIT-long running', and 'HIIT-short cycling') underlying the interventions across the included studies. Similar effectiveness in increasing CRF among the three HIIT modalities was observed. Subgroup analyses showed no significant differences in CRF by sex, weight status, study design, and baseline physical activity level (P > 0.05), but differences were observed by age group, and exercise intensity indicator was used in the HIIT programmes (P < 0.05). All three HIIT modalities produced significant improvements of CRF, although some modalities showed greater changes for some specific age groups or intensity indicators.

Does Intensity Really Matter to Improve Cardiorespiratory Fitness in Patients With Heart Failure With Preserved Ejection Fraction?

Preoperative high-intensity interval training (HIIT) is associated with improved cardiorespiratory fitness (CRF) and may improve surgical outcomes. To summarize data from studies comparing the association of preoperative HIIT vs standard hospital care with preoperative CRF and postoperative outcomes. Data sources included Medline, Embase, Cochrane Central Register of Controlled Trials Library, and Scopus databases with no language constraints, including abstracts and articles published before May 2023. The databases were searched for randomized clinical trials and prospective cohort studies with HIIT protocols in adult patients undergoing major surgery. Thirty-four of 589 screened studies met initial selection criteria. A meta-analysis was performed according to Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Data were extracted by multiple independent observers and pooled in a random-effects model. The primary outcome was change in CRF, as measured by either peak oxygen consumption (V̇o2 peak) or 6-Minute Walk Test (6MWT) distance. Secondary outcomes included postoperative complications; hospital length of stay (LOS); and changes in quality of life, anaerobic threshold, and peak power output. Twelve eligible studies including 832 patients were identified. Pooled results indicated several positive associations for HIIT when compared with standard care either on CRF (V̇o2 peak, 6MWT, anaerobic threshold, or peak power output) or postoperative outcomes (complications, LOS, quality of life), although there was significant heterogeneity in study results. In 8 studies including 627 patients, there was moderate-quality evidence of significant improvement in V̇o2 peak (cumulative mean difference, 2.59 mL/kg/min; 95% CI, 1.52-3.65 mL/kg/min; P < .001). In 8 studies including 770 patients, there was moderate-quality evidence of a significant reduction in complications (odds ratio, 0.44; 95% CI, 0.32-0.60; P < .001). There was no evidence that HIIT differed from standard care in hospital LOS (cumulative mean difference, -3.06 days; 95% CI, -6.41 to 0.29 days; P = .07). The analysis showed a high degree of heterogeneity in study outcomes and an overall low risk of bias. The results of this meta-analysis suggest that preoperative HIIT may be beneficial for surgical populations through the improvement of exercise capacity and reduced postoperative complications. These findings support including HIIT in prehabilitation programs before major surgery. The high degree of heterogeneity in both exercise protocols and study results supports the need for further prospective, well-designed studies.

A systematic review was carried out with the objective to analyze the workloads of the high intensity interval training (HIIT) protocols in treadmill, in order to identify the most used intensity percentages, administered in people with overweight or obesity; a bibliographic search was performed in SCOPUS, Web of Science, EBSCO, SCIELO and PUBMED databases. Inclusion criteria were: original experimental studies, where one or more HIIT protocols in treadmill were administered on population with overweight or obesity, regardless their age; studies made in athletes or using functional exercises were excluded. Eight articles were considered for this review from a total of 678 articles detected. All of them reported the administration of HIIT protocols at intensities between 80% and 95% of HRmax, HRpeak, calculated HRmax, or HRreserve; with short (30 seconds) to large (4 minutes) high intensity intervals. It is concluded that HIIT on a treadmill can be used on people with overweight or obesity due to its efficacy and safeness at high intensity levels and can provide optimal results in body composition, cardio respiratory fitness and other parameters such as IL-6 and TNFalpha, in addition to reduce systolic blood pressure.

A systematic review was carried out with the objective to analyze the workloads of the high intensity interval training (HIIT) protocols in treadmill, in order to identify the most used intensity percentages, administered in people with overweight or obesity; a bibliographic search was performed in SCOPUS, Web of Science, EBSCO, SCIELO and PUBMED databases. Inclusion criteria were: original experimental studies, where one or more HIIT protocols in treadmill were administered on population with overweight or obesity, regardless their age; studies made in athletes or using functional exercises were excluded. Eight articles were considered for this review from a total of 678 articles detected. All of them reported the administration of HIIT protocols at intensities between 80% and 95% of HRmax, HRpeak, calculated HRmax, or HRreserve; with short (30 seconds) to large (4 minutes) high intensity intervals. It is concluded that HIIT on a treadmill can be used on people with overweight or obesity due to its efficacy and safeness at high intensity levels and can provide optimal results in body composition, cardio respiratory fitness and other parameters such as IL-6 and TNFalpha, in addition to reduce systolic blood pressure. DOI: https://doi.org/10.54167/tecnociencia.v15i1.789

Growing evidence shows that aerobic exercise improves cognitive function. However, it is unclear how exercising at different exercise intensities affects cognitive inhibitory control in overweight/obese adults. Herein we compared the effects of 12 weeks of high-intensity interval training (HIIT), moderate-intensity continuous training (MICT), and self-selected intensity training (SSIT) on cognitive inhibitory control in overweight/obese adults. A total of 64 adults (59.4% women, 31.3 ± 7.1 years, 29 ± 2.5 kg/m²) were randomized into three walking/running groups: HIIT, MICT and SSIT. All groups performed three exercise sessions per week on an outdoor running track for 12 weeks. Cognitive inhibitory control was assessed at baseline and after the exercising programs using a computerized version of the Stroop Color-Words test. The HIIT and SSIT resulted in a faster Stroop effect (i.e. enhanced performance) when compared to MICT (p=.018; p= .026), however, there were no significant differences between the HIIT and SSIT groups (p> .05). The enhanced Stroop effect was correlated with increases in cardiorespiratory fitness after HIIT (r= −.521, p= .018) and decreases in body fat after MICT (r= .671, p= .001). These findings may suggest that overweight/obese adults performing exercise interventions at higher intensities or self-selected intensity may enhance their cognitive ability to inhibit automated behavioral responses. Highlights HIIT and/or SSIT are more effective than MICT in improving cognitive inhibitory control after 12-weeks in overweight/obese adults. Increases in cardiorespiratory fitness and decreases in body fat after HIIT and MICT were correlated with improvements in cognitive inhibitory control. Our study highlights the possibility of performing different exercise programs in an outdoor environment to improve cognitive function in overweight/obese adults.

Steep ramp test protocol for preoperative risk assessment and short-term high-intensity interval training to evaluate, improve, and monitor cardiorespiratory fitness in surgical oncology.

ABSTRACTWe aimed (1) to test the acute impact of two high-intensity interval-training (HIIT) protocols differing in the level of effort on intraocular pressure (IOP) responses, and (2) to elucidate whether the IOP responses differ between men and women. Twenty-four physically active collegiate (12 men and 12 women) performed three protocols: low-fatigue HIIT (eight 30-m sprints with 60-s of rest), high-fatigue HIIT (eight 30-m sprints with 30-s of rest), and control (walking). IOP was taken at baseline, after sprints and recovery by rebound tonometry. Our data revealed an acute IOP reduction during both HIIT protocols compared to the control condition (effect size [ES]:0.81–1.65). The differences between both HIIT protocols were generally negligible (ES<0.30), however, the reduction of IOP was moderately higher for the low-fatigue HIIT protocol after the 7th (ES: 0.67) and 8th (ES: 0.74) sprints. Women showed a more prominent lowering effect on IOP during the control condition (ES: 0.42–1.02), and during the two first sprints of both HIIT protocols (ES: 0.54–1.03). These findings highlight that a time-efficient HIIT protocol may acutely reduce IOP levels, while low-fatigue HIIT protocol could be recommended since it induced a higher reduction on IOP than the high-fatigue HIIT protocol.

Effect of Exercise in Heart Transplant Recipients

Background: Low cardiorespiratory fitness (CRF), elevated blood pressure (BP), and high fatness are cardiovascular disease risk factors. It remains unknown how fatness affects the influence of CRF on BP. Therefore, the aim was to examine whether the associations between baseline CRF and HIIT-postintervention resting BP were mediated through fatness in adolescents. Material and methods: The sample (n = 64) comprised 28 boys 36 girls aged 16 years. The analysed factors were fitness index- reflecting CRF, body fat mass (BFM), fat mass index (FMI), and body mass index (BMI). Bootstrapped mediation procedures were performed. The mediation analysis was conducted concerning the sex moderation effect. Results: The mediation effect of sex was confirmed; therefore, mediations models were designed separately for boys and girls. The results showed a statistically significant inverse relationship between baseline CRF and post-intervention systolic blood pressure (SBP) in both sexes (boys: B = −0.603, p = 0.010; girls: B = −0.394, p = 0.037). The relations between CRF and SBP revealed the mediation effect of the BFM and the FMI only in boys. Conclusions: Fatness mediated associations between CRF and SBP in boys. Therefore, both CRF and fatness are necessary to maintain positive results of the BP revealed in normal SBP ranges after HIIT.