Cardiorespiratory Fitness and Body Composition Responses to Different Intensities and Frequencies of Exercise Training in Colorectal Cancer Survivors

Effects of high-intensity interval training on physical morphology, cardiopulmonary function, and metabolic indicators in older adults: a systematic review and meta-analysis

Background

Despite the growing attention towards the efficacy of high-intensity interval training (HIIT) on older adult health, a consensus regarding the pleiotropic effects of HIIT in this population is yet to be reached. Previous studies have predominantly focused on specific outcomes or particular groups, lacking comprehensive analysis.

Objective

We aimed to conduct a systematic evaluation of the impact of HIIT on body composition, cardiopulmonary function, and metabolic parameters in older adults.

Methods

The databases searched included PubMed, Web of Science, Cochrane Library, Scopus, WanFang, and other relevant sources from the inception of the database until July 2023. Randomized controlled trials (RCTs) on the effects of HIIT on body shape, cardiopulmonary function, and metabolic parameters in the older adult were searched.

Results

A total of 87 RCTs meeting the criteria were included, involving 4,213 older adult people. Meta-analysis results showed that HIIT significantly improved body fat percentage (BF%) [MD: -1.63%, p = 0.005], maximal oxygen uptake (VO2max) [MD: 2.46 mL min-1 kg-1, p < 0.00001], maximal heart rate (HRmax) [MD: 2.83 beats min-1, p = 0.02], and high-density lipoprotein (HDL) levels [MD: 0.04 mmol L-1, p = 0.002]. However, for systolic blood pressure (SBP) [MD: 0.49 mmHg, p = 0.60], resting heart rate (HRrest) [MD: -0.95 BPM -1, p = 0.24], triglycerides (TG) [tendency for MD: -0.02 mmol L-1, p = 0.61], low-density lipoprotein (LDL) [MD: -0.04 mmol L-1, p = 0.27] had no significant effect. Sensitivity analysis found that HIIT significantly improved waist circumference (WC) [MD: -1.89 cm, p = 0.17], diastolic blood pressure (DBP) [MD: -0.63 mmHg, p = 0.23], respiratory exchange rate (RER) [MD: 0.01, p = 0.20], total cholesterol (TC) [MD: 0.10 mmol L-1, p = 0.14], and fasting plasma glucose (FPG) [MD:-0.20 mmol L-1, p = 0.08], but the results lacked robustness. There was no significant improvement in DBP [MD: -0.63 mmHg, p = 0.23] and body mass index (BMI) [MD: -0.36 kg m-2, p = 0.06].

Conclusions

HIIT has shown certain potential and advantages in improving the physical health of the older adult, especially in cardiopulmonary function. However, more high-quality studies are needed to confirm the effects of HIIT on the physical health of the older adult in the future. It also provides a reference for the clinical practice and family health management of HIIT in the older adult and the development of HIIT guidelines.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/myprospero, identifier CRD42023460252.

High-Intensity Interval Training for Cancer Patients: A Review of Key Considerations for Exercise Prescription

BACKGROUND

High-intensity interval training (HIIT) performed before, during, and after cancer treatment can attenuate the adverse effects induced by anti-cancer drugs. A clear presentation and rationale of characteristics of HIIT variables is vital to produce the expected HIIT adaptations in cancer patients. However, there are concerns regarding the HIIT protocols used in the cancer literature.

OBJECTIVES

The aims were to (1) identify the characteristics of HIIT and the formats that have been prescribed, (2) analyze which anchors have been utilized to prescribe effort and pause intensity, (3) examine characteristics of the physical tests used for HIIT prescription, and (4) identify potential adverse events related to HIIT intervention.

METHODS

This scoping review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) guidelines, including PubMed, Scopus, and Web of Science databases.

RESULTS

A total of 51 studies were retrieved, and the following results were found: (1) Only 25 studies reported all four essential variables for HIIT prescription [effort intensity (effort duration): pause intensity (pause duration)]. Of these studies, 23 used active pause and employed the following prescription (on average): [84% (116 s): 39% (118 s)] when percentage of maximal aerobic power (MAP) [maximal/peak oxygen uptake ( V O2max/peak)/MAP] was used; [124% (161 s): 55% (142 s)] when percentage of anaerobic threshold (AT) was used; [83% (230 s): 62% (165 s)] when maximal heart rate percentage (%HRmax) was used. From these 23 studies, 12 used V O2max/peak/MAP (one of the most recommended variables for HIIT prescription). Seven studies adopted the HIIT-long format, and in the remaining five studies, the format was unclear. (2) Twenty-four studies used fractions of V O2max/peak or mechanical variables like MAP as anchors for prescribing effort intensity, two studies used AT, 20 studies used fractions of HRmax/heart rate reserve, two studies used rate of perceived exertion (RPE), while one used RPE and % V O2peak concomitantly, and two studies utilized RPE/%HRmax concomitantly. Two studies utilized passive resting, 12 studies used % V O2peak/%MAP for prescribing pause intensity, four studies used AT, seven studies used %HRmax, one study used %HRmax/% V O2peak, and two studies used absolute loads. (3) Ten studies did not report the characteristics of the physical tests employed, two studies used submaximal tests, and 39 studies utilized graded exercise tests. (4) Ten studies did not report if there were adverse events associated with the exercise program, while 34 studies did not report any adverse events.

CONCLUSIONS

Only 50% of the studies provided all the necessary variables for accurate HIIT prescription, raising concerns about the replicability, comprehension, and effective application of HIIT in cancer patients. Most of the studies that reported all variables appeared to have employed the HIIT-long format. Only a few studies used more individualized anchors (e.g., AT) to prescribe HIIT-long format for cancer patients, which is considered a very heterogeneous population.

Experiences of patients with metastatic colorectal cancer participating in a supervised exercise intervention during chemotherapy

PURPOSE

Patients with metastatic colorectal cancer (mCRC) undergoing systemic treatment often experience toxicities. Although exercise may improve physical fitness and quality of life and counteract treatment toxicity, knowledge in patients with mCRC is limited. The ongoing randomized controlled AMICO trial evaluates the effects of supervised exercise on clinical outcomes. The present qualitative study was a pre-planned part of this trial aiming to capture adherence, satisfaction, and perceived effects of exercise among patients with mCRC.

METHODS

Patients with mCRC receiving first-line systemic treatment were randomized (1:1:1) to a control group or one of two supervised exercise arms including continuous aerobic exercise with either resistance exercises or high-intensity interval training. Semi-structured interviews with patients in the exercise arms were transcribed verbatim and thematically analyzed. Descriptive data on adherence (exercise logs) and satisfaction (questionnaire) was collected to complement and contextualize the qualitative findings.

RESULTS

Twenty-one patients were interviewed. Median exercise attendance was 67% [IQR 35-91], and the median satisfaction score was 8 [IQR 8-9] out of 10. Patients valued the guidance and knowledge of the physical therapist and expressed interindividual preferences regarding training content. Patients experienced that exercise improved their physical and mental wellbeing and helped them to endure treatment. Perceived exercise barriers were treatment toxicity, physical problems, and hospital appointments. Perceived exercise facilitators included adequate tailoring and internal or external motivation.

CONCLUSION

Patients with mCRC appreciated exercise during systemic treatment and perceived several beneficial effects, both physically and mentally. Exercise attendance varied and barriers were mainly treatment- and disease-related.

TRIAL REGISTRATION

Clinical trial.

GOV ID

NCT04754672. Date of registration: 04-12-2020.

The effect of lifestyle interventions on sarcopenia in advanced colorectal cancer: A systematic review

INTRODUCTION

Sarcopenia is a common syndrome in older patients with advanced colorectal cancer that is worsened during standard-of-care chemotherapy and is associated with increased chemotherapy toxicity, impaired quality of life, and poorer survival independent of cancer stage or chemotherapy response. Physical activity and nutrition interventions have been shown to support muscle mass in patients recovering from treatment for early-stage colorectal cancer. The aim of this present review was to evaluate the effect of physical activity and nutritional interventions on sarcopenia in patients with advanced colorectal cancer.

MATERIALS AND METHODS

We performed a systematic literature review of studies investigating the impact of physical activity and nutritional interventions on muscle mass in patients with advanced colorectal cancer. Relevant key words were searched in appropriate databases through December 2022. Review procedures were performed in line with guidelines from the Cochrane Handbook for systematic reviews and Synthesis Without Meta-analysis (SWiM) guidelines.

RESULTS

Twelve studies were identified with 1461 participants of which 587 had advanced colorectal cancer. Eight studies were randomised controlled trials (RCTs). Only two studies exclusively reported on the population with advanced colorectal cancer. Physical activity and nutritional interventions explored were heterogenous. Studies reporting an improvement in muscle mass utilised protein supplementation (one study), moderate intensity aerobic exercise (one study), and assisted resistance training (two studies). However, only a small number of participants with advanced colorectal cancer were included in these studies. Risk of bias was moderate to high for most studies. Recruitment to physical activity interventions was often low although adherence to supervised interventions was high. Physical activity and nutritional interventions across studies were safe.

DISCUSSION

A small number of studies with limited sample size and moderate-to-high risk of bias suggest that assisted resistance training and supported protein intake improve muscle mass in participants with cancer. However, there is currently sparse evidence for the effect of physical activity and nutritional interventions on sarcopenia in the setting of advanced and incurable colorectal cancer. Given the impact of sarcopenia in this population, further research in this area is warranted.

Effect of home-based exercise prehabilitation on postoperative outcomes in colorectal cancer surgery: a systematic review and meta-analysis

PURPOSE

Home-based exercise training may improve access to surgical prehabilitation in colorectal cancer (CRC) patients, but its efficacy remains unclear. This study systematically investigated the effects of home-based exercise prehabilitation on postoperative exercise capacity, complications, length of hospital stay, and health-related quality of life (HRQoL) in CRC patients.

METHODS

Randomized controlled trials (RCTs) comparing home-based exercise prehabilitation with control in CRC patients were eligible. We searched MEDLINE, Scopus, Web of Science, PEDro, and SPORTDiscus from their inception to June 3, 2024. Methodological quality was assessed using the PEDro scale, and certainty of evidence was assessed using GRADE. Data were synthesized using random-effects meta-analyses, with sensitivity analysis on studies with good methodological quality (PEDro score ≥ 6).

RESULTS

Eight RCTs involving 1092 participants were included. The primary analysis showed a significant improvement in postoperative 6-min walk distance following home-based exercise prehabilitation compared to control (mean difference (MD) = 30.62: 95% CI: [2.94; 57.79]; low-certainty evidence). However, sensitivity analysis revealed no significant between-group differences (MD = 22.60: 95% CI: [- 6.27; 51.46]). No significant effects of home-based exercise prehabilitation were found on postoperative complications (risk ratio = 1.00: 95% CI: [- 0.78; 1.29]; moderate-certainty evidence), length of hospital stay (MD = - 0.20: 95% CI: [- 0.65; 0.23]; moderate-certainty evidence), and HRQoL (physical functioning: MD = 2.62: 95% CI: [- 6.16; 11.39]; mental functioning: MD = 1.35: 95% CI: [- 6.95; 9.65]; low and very-low certainty evidence).

CONCLUSION

Home-based exercise prehabilitation does not reduce postoperative complications and length of hospital stay after CRC surgery. Its effects on postoperative exercise capacity and HRQoL remain uncertain due to low-quality evidence.

Barriers and enablers of adherence to high-intensity interval training among patients with cancer: a systematic review and meta-analysis

OBJECTIVE

Physical activity confers physical and psychosocial benefits for cancer patients and decreases morbidity and mortality, but adherence varies. High-intensity interval training (HIIT) is time-efficient and may improve adherence. Our aim was to determine barriers and enablers of adherence to HIIT in patients diagnosed with cancer.

DESIGN

Systematic review and meta-analysis.

DATA SOURCE

PubMed-MEDLINE, Scopus and Web of Science.

ELIGIBILITY CRITERIA

Intervention studies including patients diagnosed with any type of cancer, who engaged in HIIT with or without co-intervention in any stage of treatment and have reported outcomes for adherence.

RESULTS

Eight hundred articles were screened and 22 were included (n=807); 19 were included in the meta-analysis (n=755). Weighted adherence to HIIT was 88% (95% CI, 81% to 94%). None of the studies reported serious adverse events. Although being a woman and having breast cancer were associated with lower adherence (p<0.05), age was not (p=0.15). Adherence was significantly lower during the treatment phase in comparison with pre- and post-treatment phases, 83% versus 94% and 96%, respectively (p<0.001). Session time of more than 60 min, when unsupervised and combined with other interventions, was associated with decreased adherence (p<0.05).

CONCLUSION

Adherence to HIIT programmes among cancer patients varies and is improved when the intervention is supervised, of shorter duration, consists of solely HIIT and not in combination with other exercise and occurs during pre- and post-treatment phases. Strategies to improve adherence to HIIT in specific subpopulations may be needed to ensure all patients with cancer are provided optimal opportunities to reap the benefits associated with physical activity.

PROSPERO REGISTRATION

CRD42023430180.

Rates of compliance and adherence to high-intensity interval training: a systematic review and Meta-analyses

BACKGROUND

To determine rates of compliance (i.e., supervised intervention attendance) and adherence (i.e., unsupervised physical activity completion) to high-intensity interval training (HIIT) among insufficiently active adults and adults with a medical condition, and determine whether compliance and adherence rates were different between HIIT and moderate-intensity continuous training (MICT).

METHODS

Articles on adults in a HIIT intervention and who were either insufficiently active or had a medical condition were included. MEDLINE, EMBASE, PsychINFO, SPORTDiscus, CINAHL, and Web of Science were searched. Article screening and data extraction were completed by two independent reviewers. Risk of bias was assessed using RoB 2.0 or ROBINS-I. Meta-analyses were conducted to discern differences in compliance and adherence between HIIT vs. MICT. Sensitivity analyses, publication bias, sub-group analyses, and quality appraisal were conducted for each meta-analysis.

RESULTS

One hundred eighty-eight unique studies were included (n = 8928 participants). Compliance to HIIT interventions averaged 89.4% (SD:11.8%), while adherence to HIIT averaged 63% (SD: 21.1%). Compliance and adherence to MICT averaged 92.5% (SD:10.6%) and 68.2% (SD:16.2%), respectively. Based on 65 studies included in the meta-analysis, compliance rates were not different between supervised HIIT and MICT interventions [Hedge's g = 0.015 (95%CI: - 0.088-0.118), p = .78]. Results were robust and low risk of publication bias was detected. No differences were detected based on sub-group analyses comparing medical conditions or risk of bias of studies. Quality of the evidence was rated as moderate over concerns in the directness of the evidence. Based on 10 studies, adherence rates were not different between unsupervised HIIT and MICT interventions [Hedge's g = - 0.313 (95%CI: - 0.681-0.056), p = .096]. Sub-group analysis points to differences in adherence rates dependent on the method of outcome measurement. Adherence results should be interpreted with caution due to very low quality of evidence.

CONCLUSIONS

Compliance to HIIT and MICT was high among insufficiently active adults and adults with a medical condition. Adherence to HIIT and MICT was relatively moderate, although there was high heterogeneity and very low quality of evidence. Further research should take into consideration exercise protocols employed, methods of outcome measurement, and measurement timepoints.

REGISTRATION

This review was registered in the PROSPERO database and given the identifier CRD42019103313.

Effects of high-intensity interval training on functional performance and maximal oxygen uptake in comparison with moderate intensity continuous training in cancer patients: a systematic review and meta-analysis

INTRODUCTION

High-intensity interval training (HIIT) is an appropriate training modality to improve endurance and therefore contributes to physical performance. This review investigates the effect of HIIT on functional performance in cancer patients. We reviewed the relative peak oxygen uptake (relV̇O2PEAK) and meta-analytical compared HIIT with moderate intensity continuous training (MICT). Furthermore, we took various training parameters under consideration.

METHODS

A systematic literature search was conducted in Scopus, PubMed, and Cochrane Library databases. For the review, we included randomized controlled trials containing HIIT with cancer patients. From this, we filtered interventions with additional MICT for the meta-analysis. Outcomes of interest were various functional performance assessments and V̇O2MAX.

RESULTS

The research yielded 584 records which fit the inclusion criteria, of which 31 studies with n=1555 patients (57.4±8.6 years) could be included in the overall review and 8 studies in the meta-analysis (n=268, 59.11±5.11 years) regarding relV̇O2PEAK. Different functional outcomes were found, of which walking distance (+8.63±6.91% meters in 6-min walk test) and mobility (+2.7cm in sit and reach test) improved significantly due to HIIT. In terms of relV̇O2PEAK, the performance of cancer patients was improved by HIIT (10.68±6.48%) and MICT (7.4±4.29%). HIIT can be favored to increase relV̇O2PEAK (SMD 0.37; 95% CI 0.09-0.65; I2=0%; p=0.009). Effect sizes for relV̇O2PEAK improvements correlate moderately with total training volume (Spearman's ρ=0.49; p=0.03), whereas percentage increases do not (Spearman's ρ=0.24; p=0.14).

CONCLUSION

Functional and physical outcomes were positively altered by different HIIT protocols and forms of implementation, whereas a tendency toward more effectiveness of HIIT vs. MICT was found for relV̇O2PEAK. Future studies should include functional parameters more often, to finally allow a comparison between both training protocols in this regard.

Clinical updates on the effects of high intensity interval training (HIIT) exercise in people diagnosed with cancer. A systematic review and meta-analysis

OBJECTIVES

To provide an updated critical evaluation on the effectiveness of high intensity interval training (HIIT) on health outcomes amongst cancer survivors.

DESIGN

Systematic review and meta-analysis.

METHODS

A systematic search was conducted using databases CINAHL and Medline (via EBSCOhost platform), Scopus, Web of Science Core Collection, and the Cochrane Central Register of Controlled Trials. Randomised, controlled, exercise trials involving cancer survivors were eligible. Data on the effects of HIIT amongst individuals diagnosed with cancer at any stage were included. Risk of bias was assessed with the Mixed Methods Appraisal Tool (MMAT). Standardised mean differences (SMD) were calculated to compare differences between exercise and usual care. Meta-analyses (including subgroup analyses) were undertaken on the primary outcome of interest, which was aerobic fitness. Secondary outcomes were fatigue, quality of life, physical function, muscle strength, pain, anxiety, depression, upper-body strength, lower-body strength, systolic and diastolic blood pressure.

RESULTS

Thirty-five trials from forty-seven publications were included, with intervention durations ranging between 4 and 18 weeks. Breast cancer participants were represented in the highest number of trials (n = 13, 37 %). Significant effects in favour of HIIT exercise for improving aerobic fitness, quality of life, pain and diastolic blood pressure were observed (SMD range: 0.25-0.58, all p < 0.01).

CONCLUSIONS

Participation in HIIT exercise was associated with higher retention and improvements in aerobic fitness, quality of life, pain and diastolic blood pressure. The present results provide updated contemporary evidence for clinicians (e.g., exercise physiologists and physiotherapists) to prescribe HIIT exercise for cancer survivors to improve health before, during and following treatment.

Feasibility and acceptability of an mHealth, home-based exercise intervention in colorectal cancer survivors: A pilot randomized controlled trial

OBJECTIVE

To determine the feasibility and acceptability of an mHealth, home-based exercise intervention among stage II-III colorectal cancer (CRC) survivors within 5-years post-resection and adjuvant therapy.

METHODS

This pilot randomized controlled trial of a 12-week mHealth, home-based exercise intervention, randomly assigned CRC survivors to a high-intensity interval training (HIIT) or moderate-intensity continuous exercise (MICE) prescription. The following assessments were carried out at baseline and end-of-study (EOS): handgrip strength, short physical performance battery (SPPB), PROMIS physical function, neuropathy total symptom score-6 (NTSS-6), Utah early neuropathy scale (UENS), cardiopulmonary exercise testing, anthropometrics, and body composition via BOD POD, modified Godin leisure-time activity questionnaire. Feasibility, as defined by number of completed prescribed workouts and rate of adherence to individualized heart rate (HR) training zones, was evaluated at EOS. Acceptability was assessed by open-ended surveys at EOS. Descriptive statistics were generated for participant characteristics and assessment data.

RESULTS

Seven participants were included in this pilot study (MICE: n = 5, HIIT: n = 2). Median age was 39 years (1st quartile: 36, 3rd quartile: 50). BMI was 27.4 kg/m2 (1st quartile: 24.5, 3rd quartile: 29.7). Most participants had stage III CRC (71%, n = 5). We observed an 88.6% workout completion rate, 100% retention rate, no adverse events, and qualitative data indicating improved quality of life and positive feedback related to ease of use, accountability, motivation, and autonomy. Mean adherence to HR training zones was 95.7% in MICE, and 28.9% for the high-intensity intervals and 51.0% for the active recovery intervals in HIIT; qualitative results revealed that participants wanted to do more/work-out harder.

CONCLUSION

An mHealth, home-based delivered exercise intervention, including a HIIT prescription, among stage II-III CRC survivors' post-resection and adjuvant therapy was tolerable and showed trends towards acceptability.

Effects of high-intensity interval exercise on cardiac troponin elevation when comparing with moderate-intensity continuous exercise: a systematic review and meta-analysis

Background

This systematic review and meta-analysis aimed to compare the effects of high-intensity interval exercise (HIIE) with different recovery modes versus moderate-intensity continuous exercise (MICE) on cardiac troponin (cTn) elevation.

Methodology

A literature search was conducted in four databases: Scopus, PubMed, EBSCO and Web of Science from January 2010 to June 2022. The articles were screened, evaluated for quality before data were extracted. The review protocol was registered at PROSPERO (CRD42021245649). Standardized mean differences (SMD) of peak cTn were analyzed with a 95% confidence interval (95% CI) using Revman 5.4 software.

Results

Six studies satisfied the inclusion criteria with a total of 92 and 79 participants for HIIE and MICE, respectively. Overall, there was no significant difference between HIIE and MICE in the elevation of cardiac troponin T (SMD: 0.41 [95% CI [-0.21, 1.03]], p = 0.20, I 2 = 77%, p for heterogeneity <0.01). In subgroup analysis, HIIE with passive recovery elicits greater release of cardiac troponin T than MICE (SMD: 0.85 [95% CI [0.44, 1.27]], p < 0.01, I 2 = 32%, p for heterogeneity = 0.22). Changes of cardiac troponin T (SMD: 0.41 [95% CI [-0.21, 1.03]], p = 0.20, I 2 = 77%, p for heterogeneity < 0.01) after HIIE with active recovery were not significantly different from those of MICE.

Conclusions

There was no significant difference between HIIE and MICE in the elevation of cardiac troponin T. However, HIIE with passive recovery elicited more cardiac troponin T elevation than MICE, which should be considered when developing exercise programs.

Physical Activity in Stage III Colon Cancer: CALGB/SWOG 80702 (Alliance)

PURPOSE

To determine the specific types, durations, and intensities of recreational physical activity associated with the greatest improvements in disease-free survival (DFS) of patients with colon cancer.

METHODS

We conducted a prospective cohort study nested within a randomized multicenter trial of stage III colon cancer that compared 3 versus 6 months of fluorouracil, leucovorin, and oxaliplatin with or without celecoxib. We measured recreational physical activity in the first 3 months of chemotherapy and again 6 months after completion of chemotherapy. The primary end point was DFS.

RESULTS

During a median follow-up of 5.9 years, 457 of 1,696 patients experienced disease recurrence or death. For total recreational physical activity volume, the 3-year DFS was 76.5% with < 3.0 metabolic equivalent task hours per week (MET-h/wk) and 87.1% with ≥ 18.0 MET-h/wk (risk difference [RD], 10.6%; 95% CI, 4.7 to 19.4; P < .001). For light-intensity to moderate-intensity activities, the 3-year DFS was 65.7% with 0.0 h/wk and 87.1% with ≥ 1.5 h/wk (RD, 21.4%; 95% CI, 9.2 to 37.1; P < .001). For vigorous-intensity activity, the 3-year DFS was 76.0% with 0.0 h/wk and 86.0% with ≥ 1.0 h/wk (RD, 10.0%; 95% CI, 4.5 to 18.9; P < .001). For brisk walking, the 3-year DFS was 81.7% with < 1.0 h/wk and 88.4% with ≥ 3.0 h/wk (RD, 6.7%; 95% CI, 3.0 to 13.8; P < .001). For muscle strengthening activity, the 3-year DFS was 81.8% with 0.0 h/wk and 88.8% for ≥ 0.5 h/wk (RD, 7.0%; 95% CI, 3.1 to 14.2; P = .003).

CONCLUSION

Among patients with stage III colon cancer enrolled in a trial of postoperative treatment, larger volumes of recreational physical activity, longer durations of light- to moderate-intensity aerobic physical activity, or any vigorous-intensity aerobic physical activity were associated with the greatest improvements in DFS.

Exercise and colorectal cancer: prevention and molecular mechanisms

Exercise and physical activity have been shown to be strongly associated with a decreased incidence rate of various chronic diseases especially numerous human malignancies. A huge number of clinical trials and meta-analysis have demonstrated that exercise is significantly effective in lowering the risk of colorectal cancer. In addition, it is suggested as an effective therapeutic modality against this cancer type. Therefore, in this review, we will review comprehensibly the effects of exercise in preventing, treating, and alleviating the adverse effects of conventional therapeutic options in colorectal cancer. Moreover, the possible mechanisms underlying the positive effects of exercise and physical activity in colorectal cancer, including regulation of inflammation, apoptosis, growth factor axis, immunity, epigenetic, etc. will be also discussed.

Exercise is an effective post-treatment management program in colorectal cancer survivals

Exercise improves muscle strength, cardiorespiratory fitness, emotional distress, physical activity, fatigue, and sleep quality in colorectal patients undergoing chemotherapy

Targeting and modulating insulin-like growth factor (IGF) system, inflammation, apoptosis, immunity, epigenetic, Leptin and Ghrelin, and signaling pathways are major underlying mechanisms for preventive effects of exercise in colorectal cancer

The effects of prehabilitation on body composition in patients undergoing multimodal therapy for esophageal cancer

Prehabilitation aims to optimize a patient's functional capacity in preparation for surgery. Esophageal cancer patients have a high incidence of sarcopenia and commonly undergo neoadjuvant therapy, which is associated with loss of muscle mass. This study examines the effects of prehabilitation on body composition during neoadjuvant therapy in esophageal cancer patients. In this cohort study, changes in body composition were compared between esophageal cancer patients who participated in prehabilitation during neoadjuvant therapy and controls who did not receive prehabilitation. Assessment of body composition was performed from CT images acquired at the time of diagnosis and after neoadjuvant therapy. Fifty-one prehabilitation patients and 28 control patients were identified. There was a significantly greater fall in skeletal muscle index (SMI) in the control group compared with the prehabilitation patients (Δ SMI mean difference = -2.2 cm2/m2, 95% CI -4.3 to -0.1, p=0.038). Within the prehabilitation cohort, there was a smaller decline in SMI in patients with ≥75% adherence to exercise in comparison to those with lower adherence (Δ SMI mean difference = -3.2, 95% CI -6.0 to -0.5, P = 0.023). A greater decrease in visceral adipose tissue (VAT) was seen with increasing volumes of exercise completed during prehabilitation (P = 0.046). Loss of VAT during neoadjuvant therapy was associated with a lower risk of post-operative complications (P = 0.017). By limiting the fall in SMI and promoting VAT loss, prehabilitation may have multiple beneficial effects in patients with esophageal cancer. Multi-center, randomized studies are needed to further explore these findings.

Mediterranean Style Dietary Pattern with High Intensity Interval Training in Men with Prostate Cancer Treated with Androgen Deprivation Therapy: A Pilot Randomised Control Trial

Background: Androgen deprivation therapy (ADT) in prostate cancer has been shown to deteriorate body composition (reduced lean mass and increased body and fat mass) and increase the risk of cardiovascular morbidity. The Mediterranean style dietary pattern (MED-diet) and high intensity interval training (HIIT) may synergistically alleviate these side effects and improve quality of life in men treated with ADT. Methods: Twenty-three men (65.9 ± 7.8 years; body mass index: 29.6 ± 2.7 kg/m2; ADT duration: 33.8 ± 35.6 months) receiving ADT for ≥3 months were randomly assigned (1:1) to 20 weeks of usual care or the MED-diet (10 nutrition consults) with HIIT (4 × 4 min 85−95% heart rate peak, 3× week, starting at 12 weeks). Results: The MED-diet with HIIT significantly improved cardiorespiratory fitness (+4.9 mL·kg−1·min, p < 0.001), and body mass (−3.3 kg, p < 0.001) compared to the usual care group at 20 weeks. Clinically meaningful (≥3 points) improvements were seen in quality of life and cancer-related fatigue after 20 weeks. Conclusions: The MED-diet with HIIT increased cardiorespiratory fitness and reduced body weight in men with prostate cancer treated with ADT. Larger trials determining whether the MED-diet with HIIT translates to cardiovascular benefits are warranted.

Home-based, supervised, and mixed exercise intervention on functional capacity and quality of life of colorectal cancer patients: a meta-analysis

This systematic review and meta-analysis of randomized controlled trials tested the effects of home-based, supervised, or mixed exercise interventions on the functional capacity (FC) and quality of life (QoL) in colorectal cancer patients. A literature search was performed using the PubMed, Embase, Cochrane, and Medline databases. Two reviewers screened the literature through March 10, 2021 for studies related to exercise and colorectal cancer. Of the 1161 screened studies in the initial search, 13 studies met the eligibility criteria (home-based = 6 studies; supervised or mixed = 7 studies). Overall, 706 patients were enrolled in the trials, and 372 patients were submitted to home-based, supervised, or mixed exercise intervention. The overall results from the main meta-analysis showed a significant effect regarding supervised or mixed intervention (6 studies; p = 0.002; I² = 43%; PI 0.41–1.39); however, no significant effect was observed for home-based intervention (5 studies; p = 0.05; I² = 25%; PI − 0.34–0.76). A sensitivity analysis based on studies with intervention adherence ≥ 80% (home-based = 3 studies; supervised or mixed = 4 studies) revealed that home-based intervention or intervention entirely supervised or with some level of supervision (mixed) are effective in improving the QoL and FC of CRC patients. In summary, this meta-analysis verified that supervised and home-based exercise can modify QoL and FC when intervention adherence ≥ 80%. Regardless of the supervision characteristics, future RCTs are strongly encouraged to provide a detailed description of the exercise variables in physical interventions for CRC prescription. This perspective will allow a refined exercise prescription for patients with CRC, mainly according to their clinical status.

Attention to principles of exercise training: an updated systematic review of randomized controlled trials in cancers other than breast and prostate

BACKGROUND

The primary objective of this systematic review was to update our previous review on randomized controlled trials (RCTs) of exercise in cancers other than breast or prostate, evaluating: 1) the application of principles of exercise training within the exercise prescription; 2) reporting of the exercise prescription components (i.e., frequency, intensity, time, and type (FITT)); and 3) reporting of participant adherence to FITT. A secondary objective was to examine whether reporting of these interventions had improved over time.

METHODS

MEDLINE, EMBASE, CINAHL and SPORTDiscus databases were searched from 2012 to 2020. Eligible studies were RCTs of at least 4 weeks of aerobic and/or resistance exercise that reported on physiological outcomes relating to exercise (e.g., aerobic capacity, muscular strength) in people with cancer other than breast or prostate.

RESULTS

Eighty-six new studies were identified in the updated search, for a total of 107 studies included in this review. The principle of specificity was applied by 91%, progression by 32%, overload by 46%, initial values by 72%, reversibility by 7% and diminishing returns by 5%. A significant increase in the percentage of studies that appropriately reported initial values (46 to 80%, p < 0.001) and progression (15 to 37%, p = 0.039) was found for studies published after 2011 compared to older studies. All four FITT prescription components were fully reported in the methods in 58% of all studies, which was higher than the proportion that fully reported adherence to the FITT prescription components in the results (7% of studies). Reporting of the FITT exercise prescription components and FITT adherence did not improve in studies published after 2011 compared to older studies.

CONCLUSION

Full reporting of exercise prescription and adherence still needs improvement within exercise oncology RCTs. Some aspects of exercise intervention reporting have improved since 2011, including the reporting of the principles of progression and initial values. Enhancing the reporting of exercise prescriptions, particularly FITT adherence, may provide better context for interpreting study results and improve research to practice translation.

The association between time-of-day of habitual exercise training and changes in relevant cancer health outcomes among cancer survivors

OBJECTIVE

To assess the relationship between time-of-day of exercise training and changes in relevant cancer health outcomes among cancer survivors.

METHODS

Retrospective analysis of data collected from 2016-2019 from a hospital-based exercise oncology program. Descriptive statistics were calculated for demographic, clinical, and exercise timing characteristics (e.g. AM, PM, or mix) among survivors with available data for exercise training time (n = 233). For the total sample and a breast cancer sub-analysis, univariate analysis of covariance, adjusted for age, was carried out by exercise training time, for change in the following outcomes collected during the program's assessment sessions: cardiorespiratory fitness and muscular endurance (human performance variables), physical function, anthropometrics, self-reported fatigue, and quality of life (QoL). Change in body mass index (BMI) and body weight was included in the breast cancer analysis.

RESULTS

Overall, 37.3% of survivors habitually engaged in AM exercise (e.g. ≥ 75% AM training), 34.3% in PM exercise, and 28.3% in a mix of AM and PM exercise training throughout the program. Median time in the program was 17 weeks. Significant improvements in most human performance and physical function variables were observed in the total sample regardless of exercise training time-of-day. Among breast cancer survivors, PM but not AM or mixed was associated with improvements in fitness, and lower-body muscular endurance and function. Mixed exercise timing was linked with greater increase in waist circumference (total sample: 3.02cm, 95%CI 1.55, 4.49; breast cancer: 3.57cm 95%CI 0.96, 6.18), body weight (breast cancer: 1.6kg, 95%CI 0.3, 2.8) and BMI (breast cancer: 0.6kg/m2, 95%CI 0.1, 1.0). AM and PM exercise, but not mixed, was associated with improvements in fatigue and QoL.

CONCLUSION

Time-of-day of exercise training may differentially impact changes in human performance and physical function variables. Mixed exercise training time may result in less favorable outcomes related of weight management variables among cancer survivors.

Moderate-intensity exercise training or high-intensity interval training to improve aerobic fitness during exercise prehabilitation in patients planned for elective abdominal cancer surgery?

Low preoperative aerobic fitness is associated with an increased risk of postoperative complications and delayed recovery in patients with abdominal cancer. Surgical prehabilitation aims to increase aerobic fitness preoperatively to improve patient- and treatment-related outcomes. However, an optimal physical exercise training program that is effective within the short time period available for prehabilitation (<6 weeks) has not yet been established. In this comparative review, studies (n = 8) evaluating the effect of short-term (<6 weeks) moderate-intensity exercise training (MIET) or high-intensity interval training (HIIT) on objectively measured aerobic fitness were summarized. The content of exercise interventions was critically appraised regarding the frequency, intensity, time, type, volume, and - monitoring of - progression (FITT-VP) principles. Three out of four studies evaluating HIIT showed statistically significant improvements in oxygen uptake at peak exercise (VO_2peak) by more than 4.9%, the coefficient of variation for VO_2peak. None of the two studies investigating short-term MIET showed statistically significant pre-post changes in VO_2peak. Although short-term HIIT seems to be a promising intervention, concise description of performed exercise based on the FITT-VP principles was rather inconsistent in studies. Hence, interpretation of the results is challenging, and a translation into practical recommendations is premature. More emphasis should be given to individual responses to physical exercise training. Therefore, adequate risk assessment, personalized physical exercise training prescription using the FITT-VP principles, full reporting of physical exercise training adherence, and objective monitoring of training progression and recovery is needed to ensure for a personalized and effective physical exercise training program within a multimodal prehabilitation program.

The impact of high-intensity interval exercise training on NK-cell function and circulating myokines for breast cancer prevention among women at high risk for breast cancer

Purpose

Preclinical evidence suggests that natural killer cell (NK-cell) function and myokines facilitate the protective effects of exercise for breast cancer prevention. Since higher-intensity exercise acutely promotes greater mobilization and larger changes in NK-cell cytotoxicity than lower-intensity, high-intensity interval training (HIIT) might offer increased immune protection compared to moderate-intensity continuous-training (MICT). This study compared a 12-week HIIT program to a 12-week MICT program and usual care on changes in resting NK-cell function and circulating myokines among women at high risk for breast cancer.

Methods

Thirty-three women were randomized to HIIT, MICT, or usual care, for a supervised exercise intervention. Blood was collected at baseline and end-of-study. The cytotoxic activity of CD3−/CD56+ NK-cells against the K562 target cell line in vitro was determined by flow cytometry. Circulating myokines (IL-15, IL-6, irisin, OSM, osteonectin, IL-7) were assessed with luminex multiplex assays and ELISA. One-way ANOVA and paired sample t-tests assessed between- and within-group differences, respectively. Pearson correlation coefficients determined relationships between baseline fitness and change variables.

Results

Significant differences were not observed between groups for change in NK-cell function or circulating myokines (p > 0.05). Significant correlations were only observed for baseline peak aerobic capacity (ml/kg/min) and change in NK-cell-specific lysis (r = − 0.43, p = 0.02) and hemacytotoxicity for the total sample (r = − 0.46, p = 0.01).

Conclusion

Our findings suggest that exercise intensity may not significantly impact change in resting NK-cell function and circulating myokines among women at high risk for breast cancer. Structured exercise training may have a larger impact on NK-cell function in those with lower levels of cardiorespiratory fitness.

Clinical trial registration: NCT02923401; Registered on October 4, 2016

Exercise intervention for post-treatment colorectal cancer survivors: a systematic review and meta-analysis

PURPOSE

This study aimed to explore the effects of exercise on post-treatment colorectal cancer survivors through a systematic review and meta-analysis as the current information is limited and controversial.

METHODS

We searched PubMed, Web of Science, Embase, and Cochrane Library databases for randomized controlled trials that focused on exercise intervention for adult colorectal cancer survivors who had completed primary cancer treatment. We extracted and pooled information regarding psychosocial outcomes, physical functions, body composition, metabolic growth factors, and/or tumor-related biomarkers. All data were assessed by two independent reviewers. The risk of bias was assessed using the Cochrane Collaboration's tool.

RESULTS

A total of 20 studies, which presented data from 1223 post-treatment colorectal cancer survivors, matched the inclusion criteria. Compared with usual care or usual lifestyle, exercise intervention increased VO2peak (n = 107, SMD = 0.72, 95% CI = 0.32 to 1.11, I2 = 41%, P = 0.0004), reduced fasting insulin levels and insulin resistance (n = 150, SMD = - 0.55, 95% CI = - 0.88 to - 0.23, I2 = 0%, P = 0.0009; SMD = - 0.62, 95% CI = - 0.95 to - 0.29, I2 = 0%, P = 0.0002), and decreased levels of sICAM-1. Moderate-intensity exercise was associated with a more pro-inflammatory immune state, resulting in increased oxidative DNA damage. However, no evidence was found for effects of exercise on psychosocial outcomes or body composition.

CONCLUSIONS

Our results revealed that exercise could be a feasible and effective option for improving cardiopulmonary fitness, metabolism, and tumor-related biomarkers in post-treatment colorectal cancer survivors.

IMPLICATIONS FOR CANCER SURVIVORS

Given the benefits of exercise for colorectal cancer survivors, they should be encouraged to become more physically active.

Evaluation of an Expert Guided Integrative Therapy Concept in Patients With Breast or Gynecological Cancer During Systemic Therapy

Purpose.

Breast and gynecological cancer patients undergoing systemic therapy frequently request integrative therapy concepts. The potential of integrative therapy (IM) lies in minimizing side effects of conventional cancer treatments and therefore decreasing treatment delays. IM can help to improve patients’ physical and emotional well-being, optimizing health and quality of life as IM involves patients in their own treatment. A counseling service for integrative medicine concepts as an outpatient program was implemented in our cancer center in 2013.

Methods.

In 2016 and 2017 144 breast and gynecological cancer patients were included into our specific IM program. The program comprises biological based complementary and alternative medicines (BB-CAM), a structured exercise therapy, manipulative and body-based practices, nutritional counseling, psycho-oncological and relaxing therapies. Therapists with additional specialization for IM, guide the treatment units. The program was evaluated via self-administered questionnaire.

Results.

78% of the participating patients noticed an improvement by using BB-CAMs. 86% stated to feel better through participation in the structured exercise program. 74% profited from nutritional counseling and 91% from manual therapy. 93% of the patients treated with body compresses considered the application as soothing. The Bio-Frequency Sound Color Bed led to a relaxation in 96%. Psychological therapy improved coping with the disease in 70% of the patients.

Conclusion.

Integrative oncology combines the best practices of conventional and complementary therapy, uniting them in a holistic concept. Data show that our integrative therapy concept is well accepted by the patients and that therapy- and disease-related side effects can be reduced.

High-Intensity Interval Training Is Feasible in Women at High Risk for Breast Cancer

Purpose

This trial aimed to demonstrate the feasibility of high-intensity interval training (HIIT) in postmenopausal, overweight/obese women at high risk of invasive breast cancer and to explore HIIT on changes in cardiorespiratory fitness (CRF), body weight, and body mass index (BMI) compared with moderate-intensity continuous training (MICT) and usual care (UC).

Methods

Forty-four women were randomized to HIIT, MICT, or UC for a 12-wk, thrice weekly, supervised exercise intervention. HIIT included a 5-min warm-up at 50%–70% HR_peak, four cycles of 4 min at 90%–100% HR_peak, followed by 3 min at 50%–70% HR_peak. MICT consisted of 41 min at 60%–70% HR_peak. Feasibility was assessed by consent, adherence, compliance, and retention rates. CRF, body weight, and BMI were measured at baseline and end of study. Repeated-measures linear mixed models were used to assess within- and between-group differences.

Results

Average age was 63.9 ± 8.8 yr. BMI was 30.9 ± 5.7 kg·m⁻². Participants completed 90% and 89% of HIIT and MICT workouts, respectively, with 100% compliance to the exercise prescriptions. No serious adverse events were reported. Compared with MICT and UC, HIIT exhibited improvements in change in treadmill time (101 s greater than MICT, and 125 s greater than UC, respectively, P < 0.001). Compared with UC, HIIT exhibited improvement in changes in absolute and relative V˙O_2peak (a 0.15-L·min⁻¹ increase, P = 0.005, and a 2.3-mL·kg⁻¹⋅min⁻¹ increase, P = 0.004). There were no significant differences between groups for body weight or BMI (P > 0.05).

Conclusions

HIIT is feasible, safe, and seems to promote greater improvements in CRF compared with MICT and UC in women at high risk for breast cancer.

Facilitators and barriers to participation in lifestyle modification for men with prostate cancer: A scoping review

PURPOSE

Diet and physical activity changes have been shown to improve quality of life and health outcomes for prostate cancer (PC) survivors; however, few survivors make lifestyle changes. We aimed to identify PC-specific facilitators and barriers to dietary and physical activity changes and participation in survivorship-based lifestyle management programmes.

METHODS

A scoping review investigating facilitators and barriers of PC survivor's participation in lifestyle management programmes was conducted in June 2018. A total of 454 studies were identified, 45 studies were assessed in full, and 16 were included in the scoping review.

RESULTS

Barriers to lifestyle change included perceived lack of evidence for lifestyle guidelines, treatment side effects, perception of change as unnecessary, time pressure and age. Facilitators for lifestyle change included advice from health professionals, support systems (family and peer), diagnosis as a time for change, lifestyle as a coping strategy to manage side effects and improve well-being.

CONCLUSIONS

Health professionals, peers and family have a significant role in lifestyle management for PC survivors to facilitate engagement. Specific and clear messaging of the benefits of lifestyle management is warranted. Treatment-related side effects, time pressure, current health perception and age should be considered when developing lifestyle management programmes for PC survivors.

The effect of strength and endurance training on SSTR2 and SSTR5 in patients with colorectal cancer

The roots of apoptosis caused by the use of certain drugs in patients with colorectal cancer and certain drugs could be induced the change in genes SSTR2 and SSTR5. SSTRs play a role in colorectal cancer and it’s also known that exercise training has similar effects to certain drugs. Therefore, this study aims to evaluate the effects of a combined training program on hormonal and physiological changes in patients with colorectal cancer. Twenty patients with colorectal cancer were included in this study and divided into two groups as experimental (n=10) and control (n=10). The experimental group performed an exercise training program 5 days a week for 14 weeks. Blood samples were taken from the patients before and after the training program, and analyzed for somatostatin and its receptors. When the pretest effect excluded as statistical, there were no significant differences in SSRT2 (P>0.05) and SSRT5 (P>0.05) between the experimental and control groups. The hypothesis for this study was “SSTR2 and SSTR5 will improve after combined training program” however, in accordance with the results it was rejected. It seems that the determined training program for these patients need to be extended and performed for at least 3 months in a gradual incremental structure so that it could affect their health indicators significantly.

Peer support for the maintenance of physical activity and health in cancer survivors: the PEER trial - a study protocol of a randomised controlled trial

Background

Despite an overwhelming body of evidence showing the benefits of physical activity (PA) and exercise for cancer survivors, few survivors meet the exercise oncology guidelines. Moreover, initiating, let alone maintaining exercise programs with cancer survivors continues to have limited success. The aim of this trial is to evaluate the influence of peer support on moderate-to-vigorous PA (MVPA) and various markers of health 12 months following a brief supervised exercise intervention in cancer survivors.

Methods

Men and women previously diagnosed with histologically-confirmed breast, colorectal or prostate cancer (n = 226), who are >1-month post-treatment, will be invited to participate in this trial. Once enrolled, participants will complete 4 weeks (12 sessions) of supervised high intensity interval training (HIIT). On completion of the supervised phase, both groups will be provided with written recommendations and verbally encouraged to achieve three HIIT sessions per week, or equivalent exercise that meets the exercise oncology guidelines. Participants will be randomly assigned to receive 12 months of peer support, or no peer support (control). Primary and secondary outcomes will be assessed at baseline, after the 4-week supervised HIIT phase and at 3-, 6- and 12-months. Primary outcomes will include accelerometry-derived MVPA and prescribed HIIT session adherence; whilst secondary outcomes will include cardiorespiratory fitness (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \dot{\mathrm{V}}{\mathrm{O}}_{2\mathrm{peak}} $$\end{document}V˙O2peak), body composition, quality of life and select cytokines, myokines and inflammatory markers. Random effects mixed modelling will be used to compare mean changes in outcomes between groups at each time point. A group x time interaction will be used to formally test for differences between groups (alpha =0.05); utilising intention-to-treat analyses.

Discussion

If successful, peer support may be proposed, adopted and implemented as a strategy to encourage cancer survivors to maintain exercise beyond the duration of a short-term, supervised intervention. A peer support-exercise model has the long-term potential to reduce comorbidities, improve physical and mental wellbeing, and significantly reduce the burden of disease in cancer survivors.

Ethics

Human Research Ethics Committee of Bellberry Ltd. (#2015–12-840).

Trial registration

Australian New Zealand Clinical Trial Registry 12618001855213. Retrospectively registered 14 November 2018.

Trial registration includes all components of the WHO Trial Registration Data Set, as recommended by the ICMJE.

High-intensity interval training in the therapy and aftercare of cancer patients: a systematic review with meta-analysis

PURPOSE

This review and meta-analysis aimed to evaluate the effects of high-intensity interval training (HIIT) compared to usual care (UC) or moderate-intensity training (MIE) on physical fitness and health-related outcomes in cancer patients across all stages of therapy and aftercare.

METHODS

Databases were systematically searched in accordance with the PRISMA guidelines until October 4th, 2018. Eligibility criteria included adult patients of various cancer types, performing HIIT vs. UC or MIE. Outcomes of interest included physical fitness (cardiorespiratory fitness [VO_2peak] and functional capacity) and health-related outcomes (body composition, quality of life, cancer-related fatigue, and blood-borne biomarkers). Mean differences (MD) were calculated and pooled to generate effect sizes for VO_2peak.

RESULTS

The search identified 1453 studies, out of which 12 articles were included. The average duration of interventions was 6.7 ± 3.0 weeks, with 2.8 ± 0.5 sessions per week. The meta-analysis for VO_2peak showed superiority of HIIT compared to UC (MD 3.73; 95% CI 2.07, 5.39; p < 0.001) but not MIE (MD 1.36; 95% CI - 1.62, 4.35; p = 0.370). Similarly, no superior effects of HIIT compared to MIE were found for quality of life or changes in lean mass, while evidence was provided for a larger reduction in fat mass.

CONCLUSION

This systematic review showed that short-term HIIT induces similar positive effects on physical fitness and health-related outcomes as MIE but seems to be superior compared to UC. Thus, HIIT might be a time-efficient intervention for cancer patients across all stages of therapy and aftercare.

IMPLICATIONS FOR CANCER SURVIVORS

High-intensity interval training (HIIT) is superior compared to usucal care in improving physical fitness and health-related outcomes in cancer patients across all stages of therapy and aftercare. Currently, there is no evidence for the benefits of HIIT compared to aerobic training of moderate intensity (MIE) for changes in cardiorespiratory fitness, lean mass and patient-reported outcomes. Reductions in fat mass may be more pronounced in HIIT compared to MIE when training is performed in aftercare.