The impact of high-intensity interval training exercise on breast cancer survivors: a pilot study to explore fitness, cardiac regulation and biomarkers of the stress systems

Unraveling the link between cardiorespiratory fitness and cancer: a state-of-the-art review

Cardiorespiratory fitness (CRF) not only reflects an individual's capacity to perform physical activities but also encapsulates broader effects on the basic biology of aging. This review aims to summarize the evidence on the influence of CRF on overall and site-specific cancer risks. It delves into the biological mechanisms through which CRF may exert its effects, explores the clinical implications of these findings, identifies gaps in the current evidence base, and suggests directions for future research. The synthesis of findings reveals that higher CRF levels (general threshold of > 7 METs) are consistently associated with a reduced risk of a range of cancers, including head and neck, lung, breast, gastrointestinal, particularly pancreatic and colorectal, bladder, overall cancer incidence and mortality, and potentially stomach and liver, bile duct, and gall bladder cancers. These inverse associations between CRF and cancer risk do not generally differ across age groups, sex, race, or adiposity, suggesting a universal protective effect of CRF. Nonetheless, evidence linking CRF with skin, mouth and pharynx, kidney, and endometrial cancers is limited and inconclusive. Conversely, higher CRF levels may be potentially linked to an increased risk of prostate cancer and hematological malignancies, such as leukemia and myeloma, although the evidence is still not conclusive. CRF appears to play a significant role in reducing the risk of several cancers through various biological mechanisms, including inflammation reduction, immune system enhancement, hormonal regulation, and metabolic improvements. Overall, enhancing CRF through regular physical activity offers a vital, accessible strategy for reducing cancer risk and extending the health span. Future research should aim to fill the existing evidence gaps regarding specific cancers and elucidate the detailed dose-response relationships between CRF levels and cancer risk. Studies are also needed to elucidate the causal relationships and mechanistic pathways linking CRF to cancer outcomes.

Relevance of Cardiovascular Exercise in Cancer and Cancer Therapy-Related Cardiac Dysfunction

PURPOSE OF THE REVIEW

Cancer therapy-related cardiac dysfunction (CTRCD) has been identified as a threat to overall and cancer-related survival. Although aerobic exercise training (AET) has been shown to improve cardiorespiratory fitness (CRF), the relationship between specific exercise regimens and cancer survival, heart failure development, and reduction of CTRCD is unclear. In this review, we discuss the impact of AET on molecular pathways and the current literature of sports in the field of cardio-oncology.

RECENT FINDINGS

Cardio-oncological exercise trials have focused on variations of AET intensity by using moderate continuous and high intensity interval training, which are applicable, safe, and effective approaches to improve CRF. AET increases CRF, reduces cardiovascular morbidity and heart failure hospitalization and should thus be implemented as an adjunct to standard cancer therapy, although its long-term effect on CTRCD remains unknown. Despite modulating diverse molecular pathways, it remains unknown which exercise regimen, including variations of AET duration and frequency, is most suited to facilitate peripheral and central adaptations to exercise and improve survival in cancer patients.

Role of Gut Microbe Composition in Psychosocial Symptom Response to Exercise Training in Breast Cancer Survivors (ROME) study: protocol for a randomised controlled trial

INTRODUCTION

Breast cancer survivors have an increased risk for chronic fatigue and altered gut microbiota composition, both with negative health and quality of life affects. Exercise modestly improves fatigue and is linked to gut microbial diversity and production of beneficial metabolites. Studies suggest that gut microbiota composition is a potential mechanism underlying fatigue response to exercise. Randomised controlled trials testing the effects of exercise on the gut microbiome are limited and there is a scarcity of findings specific to breast cancer survivors. The objective of this study is to determine if fitness-related modifications to gut microbiota occur and, if so, mediate the effects of aerobic exercise on fatigue response.

METHODS AND ANALYSIS

The research is a randomised controlled trial among breast cancer survivors aged 18-74 with fatigue. The primary aim is to determine the effects of aerobic exercise training compared with an attention control on gut microbiota composition. The secondary study aims are to test if exercise training (1) affects the gut microbiota composition directly and/or indirectly through inflammation (serum cytokines), autonomic nervous system (heart rate variability) or hypothalamic-pituitary-adrenal axis mediators (hair cortisol assays), and (2) effects on fatigue are direct and/or indirect through changes in the gut microbiota composition. All participants receive a standardised controlled diet. Assessments occur at baseline, 5 weeks, 10 weeks and 15 weeks (5 weeks post intervention completion). Faecal samples collect the gut microbiome and 16S gene sequencing will identify the microbiome. Fatigue is measured by a 13-item multidimensional fatigue scale.

ETHICS AND DISSEMINATION

The University of Alabama at Birmingham Institutional Review Board (IRB) approved this study on 15 May 2019, UAB IRB#30000320. A Data and Safety Monitoring Board convenes annually or more often if indicated. Findings will be disseminated in peer-reviewed journals and conference presentations.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov, NCT04088708.

Impact of exercise on markers of B cell-related immunity: A systematic review

BACKGROUND

B cells represent a crucial component of adaptive immunity that ensures long-term protection from infection by generating pathogen-specific immunoglobulins. Exercise alters B cell counts and immunoglobulin levels, but evidence-based conclusions on potential benefits for adaptive immunity are lacking. This systematic review assessed current literatures on the impact of acute exercise and exercise training on B cells, immunoglobulins, and markers of secretory immunity in human biofluids.

METHODS

According to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, MEDLINE, Web of Science, and Embase were searched on March 8, 2023. Non-randomized controlled trials and crossover trials investigating the impact of acute exercise or exercise training on B cell counts and proportions, immunoglobulin levels, salivary flow rate, or secretory immunoglobulin A secretion rate were included. Quality and reporting of exercise training studies were assessed using the Tool for the Assessment of Study Quality and reporting in Exercise. Study characteristics, outcome measures, and statistically significant changes were summarized tabularly.

RESULTS

Of the 67 eligible studies, 22 applied acute exercise and 45 applied exercise training. All included outcomes revealed significant alterations over time in acute exercise and exercise training context, but only a few investigations showed significant differences compared to control conditions. Secretory and plasma immunoglobulin A levels were most consistently increased in response to exercise training.

CONCLUSION

B cell-related outcomes are altered by acute exercise and exercise training, but evidence-based conclusions cannot be drawn with high confidence due to the large heterogeneity in populations and exercise modalities. Well-designed trials with large sample sizes are needed to clarify how exercise shapes B cell-related immunity.

Protective effects of exercise on cardiotoxicity induced by breast cancer treatments: A systematic review and meta-analysis

OBJECTIVE

Currently, one of the main causes of death in women with breast cancer is cardiovascular disease caused by the oncologic therapies. Exercise has demonstrated positive effects on cardiovascular fitness in individuals without cancer. Therefore, the aim of this study was to evaluate the cardioprotective effects of exercise in women with breast cancer, during and after the application of their treatments.

METHODS

Systematic search was done in PubMed, Scopus, Web of Science, CINAHL, MEDLINE, SPORTDiscus, and PEDro. The articles must have been published in the last ten years; the intervention to be evaluated was to consist of an exercise program; the sample had to comprise women who were undergoing breast cancer treatment or who had completed it at the time of the intervention; and the outcome variables had to include at least one parameter for the assessment of cardiac function and/or structure.

RESULTS

Of the 28 articles identified, nine reported non-randomized controlled studies, 16 randomized clinical trials and three quasi-experimental studies. The effects of exercise on left ventricular ejection fraction, global longitudinal strain and the E/A waveforms ratio were not significant. However, its effect on VO2max was significant.

CONCLUSIONS

Exercise does not seem to be effective in avoiding the cardiotoxic effects of oncological treatment for breast cancer. Although exercise seems to mitigate the symptomatology, reflected in improved functional capacity, more long-term studies are needed.

PROSPERO REGISTRATION CODE

CRD42023391441.

The Influence of Exercise on Cancer Risk, the Tumor Microenvironment and the Treatment of Cancer

There are several modifiable factors that can be targeted to prevent and manage the occurrence and progression of cancer, and maintaining adequate exercise is a crucial one. Regular physical exercise has been shown to be a beneficial strategy in preventing cancer, potentially amplifying the effectiveness of established cancer therapies, alleviating certain cancer-related symptoms, and possibly mitigating side effects resulting from treatment. Nevertheless, the exact mechanisms by which exercise affects tumors, especially its impact on the tumor microenvironment (TME), remain uncertain. This review aims to present an overview of the beneficial effects of exercise in the context of cancer management, followed by a summary of the exercise parameters, especially exercise intensity, that need to be considered when prescribing exercise for cancer patients. Finally, we discuss the influence of exercise on the TME, including its effects on crucial immune cells (e.g., T cells, macrophages, neutrophils, natural killer cells, myeloid-derived suppressor cells, B cells), intratumor angiogenesis, and cancer metabolism. This comprehensive review provides up-to-date scientific evidence on the effects of exercise training on cancer and offers guidance to clinicians for the development of safe and feasible exercise training programs for cancer patients in clinical practice.

Racial differences in weight perception among Black and White women diagnosed with breast cancer

PURPOSE

Black women are more likely than White women to have obesity, and obesity is associated with worse breast cancer prognosis. Weight perception, however, has not been studied as a potential mediator of obesity disparities in women with breast cancer. In this study, we sought to describe racial differences and the association of lifestyle factors with weight perception.

METHODS

In this cross-sectional study design, Black and White women with a new primary breast cancer were surveyed about socio-demographics, weight perception, diet, and exercise habits. Height and weight were measured at enrollment. We classified women with a BMI ≥ 25 kg/m2 or waist circumference ≥ 88 cm who reported that they were "about the right weight" as under-perceivers. Chi-square and t tests were used to assess study variables (e.g., race, physical activity) associated with under-perception of weight. Logistic regression models were fit to evaluate for racial differences in under-perception while controlling for other covariates.

RESULTS

Of 1,197 women with newly diagnosed breast cancer, the average age was 58 years, and 909 (75.9%) were White. Nine hundred eighteen (77%) had stage I cancer, 1,035 (87%) had estrogen receptor positive cancer, and 795 (66%) were privately insured at time of diagnosis. Seven hundred eighty-nine (66%) women had abdominal obesity (waist circumference ≥ 88 cm), while 366 (31%) women had a BMI ≥ 25 kg/m2. Overall, 24% of women were under-perceivers. Compared to White women, Black women with WC ≥ 88 cm more frequently under-perceived their weight (24% vs. 14% p < 0.0001) were more obese with BMI > 30 kg/m2 (51% vs. 23%, p < 0.0001) and had lower physical activity (22% vs. 77%, p < 0.0001). After controlling for age, education, and stage, Black women remained more likely to under-perceive their weight relative to White women for those with BMI ≥ 25 kg/m2 (OR: 2.64; 95% CI: 1.4-4.6) or waist circumference ≥ 88 cm (OR: 2.89; 95% CI: 1.8-4.5). With respect to lifestyle factors, among women with BMI ≥ 25 kg/m2, those who met physical activity guidelines were less likely to under-perceive their weight compared to those who did not meet physical activity guidelines (OR: 0.37; 95% CI: 0.2-0.6), regardless of race.

CONCLUSIONS

We found racial differences in weight perception and identified social determinants and lifestyle factors such as lower education and physical inactivity that influenced under-perception of weight among newly diagnosed breast cancer patients.

IMPLICATIONS FOR CANCER SURVIVORS

Since obesity is associated with worse breast cancer outcomes, identifying optimal modifiable factors to intervene upon to support weight management among breast cancer survivors is clinically important. Breast cancer patients' perceptions about their weight provide insight that may inform lifestyle behavior interventions to reduce obesity during survivorship care.

HRV-guided training vs traditional HIIT training in cardiac rehabilitation: a randomized controlled trial

High-intensity interval training is the gold standard for cardiac rehabilitation although current revascularization therapy focuses on the recovery of autonomic nervous system balance through heart rate variability (HRV). The main objective was to analyze the effect of HRV-guided training versus high-intensity interval training on cardiorespiratory fitness, heart rate variability, quality of life, and training volume at high intensity, as well as exercise adherence, safety, and feasibility in ischemic patients. This is an 8-week cluster randomized controlled trial with an HRV-based training group (HRV-G) and a traditional HIIT group (HIIT-G). Maximal oxygen consumption, heart rate, and blood pressure were measured during the Bruce protocol treadmill test. HRV was measured with the HRV4Training application, and quality of life with the MacNew QLMI. The repeated measures ANCOVA was used with the age and the baseline scores as covariables. Forty-six patients (mean age 55 ± 11.03 years) were randomized and assigned either to HRV-G (n = 23) or HIIT-G (n = 23). Both groups improved maximal oxygen consumption and METS (P > .05). However, the resting systolic blood pressure was lower in HRV-G (4.3 ± 1.2 mmHg, P = .05). In HRV-G, the resting diastolic, maximal diastolic, and systolic blood pressure decreased (5.4 ± 5.96 mmHg, P = .007; 11.4 ± 12.46 mmHg, P = .005; and 5 ± 5.98 mmHg, P = .013, respectively) whereas the recovery heart rate increased significantly (-21.5 ± 23.16 beats/min, P = .003). The LnrMSSDcv ([LnrMSSDSD/LnrMSSDMEAN] × 100) was lower in HRV-G (1.23 ± 0.91 mmHg, P = .03) while the training volume at high intensity was higher in HIIT-G (31.4 ± 29.2 min, P = .024). HRV-guided training presents a better cardioprotective effect than HIIT-G at a lower high-intensity training volume.

The augmentation of cytotoxic immune cell functionality through physical exertion bolsters the potency of chemotherapy in models of mammary carcinoma

BACKGROUND

Mammary carcinoma, a pervasive and potentially lethal affliction, is conjectured to be profoundly influenced by physical exercise, both in prophylaxis and therapeutic contexts. This study endeavors to explore the repercussions of exercise training on the progression of mammary carcinoma, particularly the mechanisms by which the amalgamation of an exercise regimen and doxorubicin induces tumor cell apoptosis.

METHODS

Female BALB/c mice were categorized into four distinct groups: A sedentary group (SED), an exercise group (Ex), a doxorubicin group (Dox, 5 mg/kg), and a combined treatment group (Dox + Ex). The exercise training lasted for 21 days and included aerobic rotarod exercise and resistance training. The impact of exercise training on tumor growth, immune cell proportions, inflammatory factor levels, and cell apoptosis pathway was assessed.

RESULTS

Exercise training significantly curtailed tumor growth in a mouse model of breast cancer. Both the Ex and Dox groups exhibited significant reductions in tumor volume and weight (p < 0.01) in comparison to the SED group, while the Dox + Ex group had a significantly lower tumor volume and weight than the Dox group (p < 0.01). Exercise training also significantly increased the proportion of NK and T cells in various parts of the body and tumor tissue, while decreasing tumor blood vessels density. Exercise training also increased IL-6 and IL-15 levels in the blood and altered the expression of apoptosis-related proteins in tumor tissue, with the combined treatment group showing even more significant changes.

CONCLUSIONS

Physical training improves the effectiveness of doxorubicin in treating breast cancer by activating cytotoxic immune cells, releasing tumor suppressor factors, and initiating mt-apoptosis, all while mitigating the adverse effects of chemotherapy.

Association Between Physical Activity Levels in Different Domains and Cardiac Autonomic Modulation in Breast Cancer Survivors: A Cross-sectional Study

BACKGROUND

Breast cancer survivors frequently present cardiac autonomic dysfunction. Physical activity (PA) has been associated with better cardiac autonomic modulation (CAM) in breast cancer survivors.

OBJECTIVE

This study aimed to analyze the association between CAM and PA levels performed in different domains (work and occupation, sport and exercise, and leisure time and commuting) in breast cancer survivors.

METHODS

This is a cross-sectional study with 99 breast cancer survivors (age, 55.3 ± 10.4 years). Cardiac autonomic modulation was assessed by heart rate variability, and PA levels at work and occupation, sport and exercise, and leisure time and commuting were assessed using the Baecke PA questionnaire. The sum of these 3 domains provided the total PA. The Mann-Whitney test was used to compare CAM between active and inactive women in different domains of PA.

RESULTS

Cardiac autonomic modulation was similar between active and inactive women in the different domains ( P > .05). However, when considering the total PA, active breast cancer survivors presented higher SDNN (average standard deviation of all normal RR intervals) (20.0 ± 13.4 vs 28.8 ± 14.0; P = .008) and SD2 (standard deviation of the long-term intervals between consecutive heartbeats) indices (29.2 ± 17.3 vs 38.7 ± 19.9; P = .005) compared with their inactive counterparts.

CONCLUSION

Breast cancer survivors with higher total PA presented better CAM compared with their less active peers.

IMPLICATIONS FOR PRACTICE

The results of this study are promising and show the importance of increasing PA levels in different domains for the maintenance of cardiovascular health among breast cancer survivors.

The Role of Exercise in Cancer-Related Sarcopenia and Sarcopenic Obesity

One of the most common adverse effects of cancer and its therapeutic strategies is sarcopenia, a condition which is characterised by excess muscle wasting and muscle strength loss due to the disrupted muscle homeostasis. Moreover, cancer-related sarcopenia may be combined with the increased deposition of fat mass, a syndrome called cancer-associated sarcopenic obesity. Both clinical conditions have significant clinical importance and can predict disease progression and survival. A growing body of evidence supports the claim that physical exercise is a safe and effective complementary therapy for oncology patients which can limit the cancer- and its treatment-related muscle catabolism and promote the maintenance of muscle mass. Moreover, even after the onset of sarcopenia, exercise interventions can counterbalance the muscle mass loss and improve the clinical appearance and quality of life of cancer patients. The aim of this narrative review was to describe the various pathophysiological mechanisms, such as protein synthesis, mitochondrial function, inflammatory response, and the hypothalamic-pituitary-adrenal axis, which are regulated by exercise and contribute to the management of sarcopenia and sarcopenic obesity. Moreover, myokines, factors produced by and released from exercising muscles, are being discussed as they appear to play an important role in mediating the beneficial effects of exercise against sarcopenia.

Comparison of the effects of high-intensity interval and moderate-intensity continuous training on inflammatory markers, cardiorespiratory fitness, and quality of life in breast cancer patients

BACKGROUND

As the effectiveness of breast cancer treatment has improved, a growing number of long-term breast cancer survivors are seeking help for unique health problems. These patients may be at increased risk of cardiovascular disease due to the side effects of treatment. The positive impact of most types of exercise has been repeatedly reported in people with cancer, but the most effective exercise approaches for maximum beneficial adaptations remain controversial. Thus, this study aimed to compare the effects of high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) on inflammatory indices, adipokines, metabolic markers, body composition, cardiorespiratory fitness, and quality of life in breast cancer patients during adjuvant endocrine therapy.

METHODS

Thirty non-metastatic breast cancer patients during adjuvant endocrine therapy who had been treated with chemotherapy and/or radiotherapy were recruited from Iran and randomized to HIIT, MICT, or control groups for a supervised exercise intervention that took place 3 times a week for 12 weeks. The training intensity was determined based on the peak oxygen uptake (VO2peak), and the volume of training was matched in HIIT and MICT based on the VO2peak. Body composition, functional capacity, cardiorespiratory fitness, metabolic indices, sex hormones, adipokines, and inflammatory markers were assessed before and after the intervention.

RESULTS

The VO2peak increased by 16.8% in the HIIT group in comparison to baseline values (mean difference = 3.61 mL/kg/min). HIIT significantly improved the VO2peak compared to control (mean difference = 3.609 mL/kg/min) and MICT (mean differences = 2.974 mL/kg/min) groups. Both HIIT (mean difference = 9.172 mg/dL) and MICT (mean difference = 7.879 mg/dL) interventions significantly increased high-density lipoprotein cholesterol levels compared to the control group. The analysis of covariance showed that physical well-being significantly improved in MICT compared to control group (mean difference = 3.268). HIIT significantly improved the social well-being compared to the control group (mean difference = 4.412). Emotional well-being subscale was significantly improved in both MICT (mean difference = 4.248) and HIIT (mean difference = 4.412) compared to the control group. Functional well-being scores significantly increased in HIIT group compared with control group (mean difference = 3.35) . Significant increase were also observed in total functional assessment of cancer therapy-General scores in both HIIT (mean difference = 14.204) and MICT groups (mean difference = 10.036) compared with control group. The serum level of suppressor of cytokine signaling 3 increased significantly (mean difference = 0.09 pg/mL) in the HIIT group compared to the baseline. There were no significant differences between groups for body weight, body mass index, fasting blood glucose, insulin resistance, sex hormone binding globulin, total cholesterol, low-density lipoprotein cholesterol, adipokines, interleukin-6, tumor necrosis factor-α, or interleukin-10.

CONCLUSION

HIIT can be used as a safe, feasible, and time-efficient intervention to improve cardiovascular fitness in breast cancer patients. Both HIIT and MICT modalities enhance quality of life. Further large-scale studies will help determine whether these promising results translate into improved clinical and oncological outcomes.

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.

An online home-based exercise program improves autonomic dysfunction in breast cancer survivors

Introduction: Exercise interventions for breast cancer survivors have proved their potential to improve clinical, physical, and psychosocial outcomes. However, limited studies have explored exercise effects on autonomic dysfunction and the measurement of exercise tolerance and progression through daily heart rate variability (HRV). Purpose: To analyze the effects of a 16-wk exercise intervention on the autonomic modulation of breast cancer survivors, as well as to examine the evolution of daily measured HRV and its interaction with exercise sessions in this population. Methods: A total of 29 patients who had undergone chemotherapy and radiotherapy were randomly assigned to the exercise group or to the control group. The exercise intervention was delivered remotely through online meetings and consisted of supervised training resistance and cardiovascular exercise 3 times per week. During the intervention all patients measured their HRV daily obtaining the napierian logarithm of the root mean square of successive differences between normal heartbeats (lnrMSSD) and the napierian logarithm of the standard deviation of the interbeat interval of normal sinus beats (lnSDNN) values at four moments: day 0 (the morning of the training sessions), 24, 48, and 72 h after exercise. Results: The results revealed a significant interaction between group and months during the intervention period for lnrMSSD and lnSDNN (p < 0.001). Additionally, there were significant differences in lnSDNN recovery time between months (p < 0.05), while differences in lnrMSSD become apparent only 24 h after exercise (p = 0.019). The control group experienced a significant decrease in both variables monthly (p < 0.05) while exercise group experienced a significant increment (p < 0.05). Conclusion: HRV is daily affected by exercise training sessions in cancer patients. Although results strongly support the role of exercise as a post-chemotherapy and radiotherapy rehabilitation strategy for breast cancer survivors to improve autonomic imbalance, further research is necessary to validate these initial findings.

High-intensity interval training in breast cancer patients: A systematic review and meta-analysis

BACKGROUND

Women with breast cancer and improved survival often experience treatment-related impairments. High-intensity interval training (HIIT) has emerged as a promising exercise therapy modality for adult cancer patients. However, the overall effects of HIIT in breast cancer patients remain scarce and controversial. Therefore, we conducted a systematic review and meta-analysis to comprehensively evaluate the impact of HIIT on health-related outcomes in breast cancer patients.

METHODS

We searched the PubMed, Embase, and Web of Science from inception to November 7, 2022. Eligible studies included randomized controlled trials that compared HIIT interventions with usual care (UC) or MICT in breast cancer patients. The primary outcome assessed was physical fitness, and exploratory outcomes included body composition, blood-borne biomarkers, and patient-reported outcomes. Summary data were extracted, and standardized mean differences (SMD) were calculated for meta-analysis. For outcomes that could not be pooled, a systematic review was conducted.

RESULTS

Our analysis included 19 articles from 10 studies, encompassing 532 participants who met the inclusion criteria. Pooled results demonstrated that HIIT was superior to UC in improving peak oxygen uptake (VO2peak ). The SMD for VO2peak (L/min) and VO2peak (mL/kg/min) was 0.79 (95% CI 0.13, 1.45) and 0.59 (95% CI 0.01, 1.16), respectively. No significant differences in VO2peak were found between the HIIT and MICT groups. Meta-analyses on body composition and blood-borne biomarkers showed no significant differences between HIIT and UC. Systematic review indicated favorable effects of HIIT on muscle strength, fatigue, and emotional well-being.

CONCLUSIONS

HIIT is a time-efficient alternative to MICT for improving VO2peak and may also enhance muscle strength and alleviate fatigue and emotional symptoms in breast cancer patients. HIIT should be considered as an important component of exercise prescription in breast cancer care. Further studies with larger cohorts are needed to determine the clinical significance of HIIT-induced changes in terms of other outcomes in women with breast cancer.

Evaluation of the MOVE online exercise programme for young people aged 13-30

PURPOSE

To evaluate the MOVE exercise programme in supporting the recovery of young people affected by cancer.

METHODS

Participants in an 8-week exercise rehabilitation programme delivered online by cancer rehabilitation specialists completed self-reported questionnaires at baseline and after programme completion. Assessments included cancer-related fatigue (FACIT fatigue scale) and health-related quality of life (EORTC-QLC-30). Qualitative data were provided through written accounts of participant experiences and underwent content analysis.

RESULTS

Seventy-one participants commenced the exercise rehabilitation programme and 57 completed the programme and provided data for analysis (63% female; median age 22 years). Statistically significant improvements were observed in post-programme scores for all measured outcomes (cancer-related fatigue, quality of life, physical functioning, role functioning, emotional functioning). Content analysis of written experiences generated ten unique codes. The highest frequency codes were enjoyment (n = 34), motivation (n = 14) and fitness (n = 13).

CONCLUSIONS

These findings indicate feasibility of delivery, acceptability to patients and physical and psychological benefits of a personalised online exercise rehabilitation programme for young people living with and beyond cancer. Further research involving a control arm and long-term follow-up would be beneficial.

IMPLICATIONS FOR CANCER SURVIVORS

These results support the inclusion of a personalised exercise programme as part of cancer rehabilitation for young people living with and beyond cancer.

Cardiovascular Dysautonomia in Patients with Breast Cancer

Breast cancer is the most frequent malignant disease among women, being responsible for a considerable percentage of fatalities and comorbidities every year. Despite advances in early detection and therapy, evidence shows that breast cancer survivors are at increased risk of developing other chronic conditions, such as cardiovascular diseases.

Autonomic dysfunction is an emerging, but poorly understood topic that has been suggested as a risk factor for cardiovascular disease in breast cancer patients. It clinically manifests through persistently elevated heart rates and abnormal heart rate variability, even before any signs of cardiovascular dysfunction appear. Since changes in the left ventricular ejection fraction only manifest when myocardial injury has already occurred, it has been hypothesized that autonomic dysfunction can constitute an early biomarker of cardiovascular impairment in breast cancer patients.

This review focuses on the direct and indirect effects of cancer and its treatment on the autonomic nervous system in breast cancer patients. We highlight the mechanisms potentially involved in cancer and antineoplastic therapy-related autonomic imbalance and review the potential strategies to prevent and/or attenuate autonomic dysfunction.

There are gaps in the current knowledge; more research in this area is needed to identify the relevance of autonomic dysfunction and define beneficial interventions to prevent cardiovascular disease in breast cancer patients.

[Non-pharmalogical interventions and breast cancer: What benefit in addition to radiotherapy?]

Adjuvant radiotherapy is one of the major anticancer treatments in early breast cancer patients. Acute and late radio-induced effects may occur during or after breast cancer radiotherapy, and their medical management is a major issue for radiation oncologists. Here, the present review of literature embraces complementary non-pharmacological interventions, which could be combined to adjuvant radiotherapy in order to improve patients care.

Acute and Chronic Effects of Interval Training on the Immune System: A Systematic Review with Meta-Analysis

Simple Summary

Interval training (IT) is a popular training strategy recognized by its positive effects on metabolic and cardiovascular system. However, there seems no consensus regarding the effects of IT on immune system parameters. Therefore, we aimed to summarize the evidence regarding the effects of IT on the immune system. As our many findings, an IT acutely promote a transitory change on immune cell count followed by reduced function. The magnitude of these changes seems to vary in accordance with IT type. On the other hand, the regular practice of IT might contribute to improve immune function without apparent change on immune cell count.

Abstract

Purpose: To summarize the evidence regarding the acute and chronic effects of interval training (IT) in the immune system through a systematic review with meta-analysis. Design: Systematic review with meta-analysis. Data source: English, Portuguese and Spanish languages search of the electronic databases Pubmed/Medline, Scopus, and SciELO. Eligibility criteria: Studies such as clinical trials, randomized cross-over trials and randomized clinical trials, investigating the acute and chronic effects of IT on the immune outcomes in humans. Results: Of the 175 studies retrieved, 35 were included in the qualitative analysis and 18 in a meta-analysis. Within-group analysis detected significant acute decrease after IT on immunoglobulin A (IgA) secretory rate (n = 115; MD = −15.46 µg·min⁻¹; 95%CI, −28.3 to 2.66; p = 0.02), total leucocyte count increase (n = 137; MD = 2.58 × 10³ µL⁻¹; 95%CI, 1.79 to 3.38; p < 0.001), increase in lymphocyte count immediately after exercise (n = 125; MD = 1.3 × 10³ µL⁻¹; 95%CI, 0.86 to 1.75; p < 0.001), and decrease during recovery (30 to 180 min post-exercise) (n = 125; MD = −0.36 × 10³ µL⁻¹;−0.57 to −0.15; p < 0.001). No effect was detected on absolute IgA (n = 127; MD = 47.5 µg·mL⁻¹; 95%CI, −10.6 to 105.6; p = 0.11). Overall, IT might acutely reduce leucocyte function. Regarding chronic effects IT improved immune function without change leucocyte count. Conclusion: IT might provide a transient disturbance on the immune system, followed by reduced immune function. However, regular IT performance induces favorable adaptations on immune function.

The Effects of High-Intensity Interval Training vs. Moderate-Intensity Continuous Training on Inflammatory Markers, Body Composition, and Physical Fitness in Overweight/Obese Survivors of Breast Cancer: A Randomized Controlled Clinical Trial

Background: Chronic inflammation associated with breast cancer (BC) poses a major challenge in care management and may be ameliorated by physical activity. This randomized controlled trial assessed the effects of a 12-week high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) on inflammatory markers, body composition, and physical fitness in BC survivors (BCS). Methods: Forty BCS (age = 57 ± 1 years; body mass [BM] = 74.8 ± 1.5 kg; VO2peak = 20.8 ± 2.1 mL·kg-1·min-1) were randomly assigned to three groups: HIIT (n = 15), MICT (n = 15), or control (CON; n = 15). The intervention groups (HIIT and MICT) performed their respective exercise protocols on a cycle ergometer 3 days/week for 12 weeks while the CON group maintained their current lifestyle. Baseline and post-intervention assessments included body composition (BM, fat mass (FM), lean mass (LM)), physical fitness (VO2peak, lower body strength (LBS), upper body strength (UBS)), and serum concentrations of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), interleukin-8 (IL-8), interleukin-10 (IL-10), leptin, and adiponectin. Results: Both intervention groups significantly (p < 0.05) decreased BM (HIIT = -1.8 kg, MICT = -0.91 kg), FM (HIIT = -0.81 kg, MICT = -0.18 kg), TNF-α (HIIT = -1.84 pg/mL, MICT = -0.99 pg/mL), IL-6 (HIIT = -0.71 pg/mL, MICT = -0.36 pg/mL), leptin (HIIT = -0.35 pg/mL, MICT = -0.16 pg/mL) and increased VO2peak (HIIT = 0.95 mL·kg-1·min-1, MICT = 0.67 mL·kg-1·min-1), LBS (HIIT = 2.84 kg, MICT = 1.53 kg), UBS (HIIT = 0.53 kg, MICT = 0.53 kg), IL-10 (HIIT = 0.63 pg/mL, MICT = 0.38 pg/mL), and adiponectin (HIIT = 0.23 ng/mL, MICT = 0.1 ng/mL) compared to baseline. The changes in BM, FM, TNF-α, leptin, and LBS were significantly greater in HIIT compared to all other groups. Conclusions: Our findings indicate that compared to the often-recommended MICT, HIIT may be a more beneficial exercise therapy for the improvement of inflammation, body composition and LBS in BCS; and consequently, merits long-term study.

Effects of a Home-Based Lifestyle Intervention Program on Cardiometabolic Health in Breast Cancer Survivors during the COVID-19 Lockdown

This study aimed to evaluate the cardiometabolic effects of a home-based lifestyle intervention (LI) in breast cancer survivors (BCSs) during the COVID-19 lockdown. In total, 30 BCSs (women; stages 0-II; non-metastatic; aged 53.5 ± 7.6 years; non-physically active; normal left ventricular systolic function) with a risk factor for recurrence underwent a 3-month LI based on nutrition and exercise. Anthropometrics, Mediterranean diet adherence, physical activity level (PAL), cardiorespiratory fitness (VO2max), echocardiographic parameters, heart rate variability (average standard deviation of NN intervals (ASDNN/5 min) and 24 h very- (24 hVLF) and low-frequency (24 hLF)), and metabolic, endocrine, and inflammatory serum biomarkers (glycemia, insulin resistance, progesterone, testosterone, and high-sensitivity C-reactive protein (hs-CRP)) were evaluated before (T0) and after (T1) the LI. After the LI, there were improvements in: body mass index (kg/m2: T0 = 26.0 ± 5.0, T1 = 25.5 ± 4.7; p = 0.035); diet (Mediet score: T0 = 6.9 ± 2.3, T1 = 8.8 ± 2.2; p < 0.001); PAL (MET-min/week: T0 = 647 ± 547, T1 = 1043 ± 564; p < 0.001); VO2max (mL·min-1·kg-1: T0 = 30.5 ± 5.8, T1 = 33.4 ± 6.8; p < 0.001); signs of diastolic dysfunction (participants: T0 = 15, T1 = 10; p = 0.007); AS-DNN/5 min (ms: T0 = 50.6 ± 14.4, T1 = 55.3 ± 16.7; p = 0.032); 24 hLF (ms2: T0 = 589 ± 391, T1 = 732 ± 542; p = 0.014); glycemia (mg/dL: T0 = 100.8 ± 11.4, T1 = 91.7 ± 11.0; p < 0.001); insulin resistance (HOMA-IR score: T0 = 2.07 ± 1.54, T1 = 1.53 ± 1.11; p = 0.005); testosterone (ng/mL: T0 = 0.34 ± 0.27, T1 = 0.24 ± 0.20; p = 0.003); hs-CRP (mg/L: T0 = 2.18 ± 2.14, T1 = 1.75 ± 1.74; p = 0.027). The other parameters did not change. Despite the home-confinement, LI based on exercise and nutrition improved cardiometabolic health in BCSs.

Effectiveness of physical exercise on the cardiovascular system in breast cancer patients: a systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

The primary purpose of this study is to structure the available evidence relating to physical exercise programs and their impact on patients' cardiovascular system during the convalescence for breast cancer.

METHODS

We searched six English databases and four Chinese databases from inception to May 19, 2021. Two reviewers independently screened literature, extracted data. They assessed the risk of bias according to the eligibility criteria, and the Cochrane Collaboration RevMan 5.3.0 version software and STATA 15.0 software were used for this meta-analysis. This study has been registered in the International Prospective Register of Systematic Reviews (CRD42021226319).

RESULTS

In total, 3483 articles were screened and data from 11 randomized controlled trials (RCTs) involving 666 breast cancer patients were used in this meta-analysis. The results showed that exercise could decrease systolic blood pressure (SBP) (P = 0.006), diastolic blood pressure (DBP) (P = 0.0003), triglycerides (TG) levels (P < 0.00001), body mass index (BMI) (P = 0.009). Results also showed that exercise could significantly increase peak oxygen uptake (VO2peak) (P = 0.009), maximal oxygen consumption (VO2max) (P = 0.01), and High-density leptin cholesterol (HDL-C) levels (P < 0.0001). However, compared with the control group, there was no significant changes of mean arterial pressure (MAP), peak heart rate (HRpeak), and peak respiratory exchange ratio (PERpeak) (P > 0.05).

CONCLUSIONS

Physical exercise could improve the cardiovascular system function associated with decreased the levels of SBP, DBP, TG, and increased the levels of VO2peak, VO2max, and HDL-C in breast cancer patients. These findings reveal that exercise may be a promising means for cardiovascular nursing.