Beneficial Effects Of Exercise Training Research Articles

12509 Identification Of Novel Exercise Training-induced Circulating Proteins: Hemostatic, Apoptotic, And Key Neuronal Factors

Abstract Disclosure: A. Shalit: None. M. Vamvini: None. P. Nigro: None. L.K. Simpson: None. H. Pan: None. J.M. Dreyfuss: None. L.J. Goodyear: Grant Recipient; Self; Daiichi Sankyo. R.J. Middelbeek: None. Exercise training induces a plethora of health benefits including improved glucose homeostasis, decreased cardiovascular disease, and improved cognitive function. An emerging concept is that many of these beneficial effects of exercise are mediated through the secretion of humoral factors into the blood. Identification of these exercise-regulated factors hold promise for novel treatments for disease. Here, we performed proteomic analysis to discover novel circulating factors in response to endurance exercise training in human participants. Given that nutritional status can affect the circulating proteome, another aim was to determine if proteomic adaptations to exercise training have similar effects under both fasted and random-fed conditions. Sedentary normoglycemic participants (3M/5F, age 22-41y) performed a supervised 10-week exercise training program, which by week 4 was 4x60 min exercise at 65-70% V̇O2peak. Fasted and random-sampling morning blood draws were collected pre-training and between 24-72 hours following the final training session. Proteomic detection was by SOMAscan. Exercise training significantly improved V̇O2peak by 17% (p=0.003). Out of 1,310 detected proteins, exercise training significantly changed 293 proteins in the fasted state and 360 proteins in the random-sampling state (p<0.05). Integration showed that 172 proteins were changed under both nutritional conditions (123 upregulated and 49 downregulated). Gene Set Enrichment Analysis (GSEA) of the commonly upregulated proteins showed that training resulted in enrichment in neuronal, hemostatic, and apoptotic pathways, whereas the downregulated proteins were enriched in neuronal and extracellular matrix processes. Since neuronal pathways were identified in both up and downregulated proteins, we focused our analysis there, identifying 31 upregulated and 4 downregulated neuronally-associated proteins. Importantly, exercise training reduced levels of CDK5, a protein that is hyperactivated in neurodegeneration and Alzheimer's disease. Moreover, GSTP1, a direct inhibitor of CDK5, along with downstream proteins inhibited by CDK5 (RAC1, STUB1, 14-3-3ε/YWHAE, HSP90AA1, CFL1), were significantly increased following exercise training.In conclusion, exercise training regulates circulating factors involved in neuronal, hemostatic, apoptotic, and extracellular matrix pathways, with these effects being independent of nutritional status. Our finding of exercise training-induced decreases in multiple proteins of the CDK5 pathway, a pathway whose downregulation is associated with neuroprotection, identify CDK5 as a novel and potentially important mediator of the beneficial effects of exercise training on cognitive function. Presentation: 6/1/2024

Testing home-based exercise strategies in underserved minority cancer patients undergoing chemotherapy (THRIVE) trial: a study protocol.

Higher rates of physical inactivity and comorbid conditions are reported in Hispanic/Latinx and Black cancer patients receiving chemotherapy compared to their White counterparts. Despite the beneficial effect of exercise training for cancer patients, rates of participation in exercise oncology clinical trials are low among disadvantaged and racial and ethnic minority groups. Here, we will examine the effect of an exercise intervention using a novel, accessible, and cost-effective home-based exercise approach among Hispanic/Latinx and Black cancer patients receiving chemotherapy on exercise participation and cardiovascular disease risk. The THRIVE trial is an 8-month prospective, three-arm study of 45 patients who are randomized in a 1:1:1 fashion to a supervised exercise intervention (SUP), unsupervised exercise (UNSUP), or an attention control (AC) group. Eligible patients include those with breast, colorectal, or prostate cancer, who are sedentary, overweight or obese, self-identify as Hispanic/Latinx or Black, and plan to receive chemotherapy. Patients randomized to the SUP group participate in a home-based 16-week periodized aerobic and resistance exercise program performed three days per week, supervised through video conference technology. Patients randomized to the UNSUP group participate in an unsupervised 16-week, telehealth-based, periodized aerobic and resistance exercise program performed three days per week using the same exercise prescription parameters as the SUP group. Patients randomized to the AC group receive a 16-week home-based stretching program. The primary outcome is changes in minutes of physical activity assessed by 7-day accelerometry at post-intervention. Secondary outcomes include cardiovascular risk factors, patient-reported outcomes, and physical function. Outcome measures are tested at baseline, post-intervention at month 4, and after a non-intervention follow-up period at month 8. The THRIVE trial is the first study to employ a novel and potentially achievable exercise intervention for a minority population receiving chemotherapy. In addition, this study utilizes an intervention approach to investigate the biological and behavioral mechanisms underlying exercise participation in these cancer patients. Results will guide and inform large randomized controlled trials to test the effect of home-based exercise on treatment outcomes and comorbid disease risk in minority patients with cancer undergoing chemotherapy. https://classic.clinicaltrials.gov/ct2/show/NCT05327452, identifier (NCT#05327452).

Role of Irisin in exercise training-regulated endoplasmic reticulum stress, autophagy and myogenesis in the skeletal muscle after myocardial infarction.

Patients with heart failure (HF) are often accompanied by skeletal muscle abnormalities, which can lead to exercise intolerance and compromise daily activities. Irisin, an exercise training (ET) -induced myokine, regulates energy metabolism and skeletal muscle homeostasis. However, the precise role of Irisin in the benefits of ET on inhibiting skeletal muscle atrophy, particularly on endoplasmic reticulum (ER) stress, autophagy, and myogenesis following myocardial infarction (MI) remains unclear. In this study, we investigated the expression of Irisin protein in wild-type mice with MI, and assessed its role in the beneficial effects of ET using an Fndc5 knockout mice. Our findings revealed that MI reduced muscle fiber cross-sectional area (CSA), while downregulating the expression of Irisin, PGC-1α and SOD1. Concurrently, MI elevated the levels of ER stress and apoptosis, and inhibited autophagy in skeletal muscle. Conversely, ET mitigated ER stress and apoptosis in the skeletal muscle of infarcted mice. Notably, Fndc5 knockout worsened MI-induced ER stress and apoptosis, suppressed autophagy and myogenesis, and abrogated the beneficial effects of ET. In conclusion, our findings highlight the role of Irisin in the ET-mediated alleviation of skeletal muscle abnormalities. This study provides valuable insights into MI-induced muscle abnormalities and enhances our understanding of exercise rehabilitation mechanisms in clinical MI patients.

High-Intensity Interval Training Decreases Circulating HMGB1 in Individuals with Insulin Resistance; Plasma Lipidomics Identifies Associated Cardiometabolic Benefits.

Background: Exercise is a fundamental primary standard of care for cardiometabolic health. Body Weight (BW) High-Intensity Interval Training (HIIT) is an effective strategy for reducing cardiometabolic markers in individuals with insulin resistance and Type-2 diabetes (T2D). High-mobility group box 1 (HMGB1), a ubiquitous nuclear factor, plays an ample role beyond an alarmin in T2D development and progression. Our group has described this novel role previously, showing the beneficial effect of whole body HMGB1 silencing in decreasing hyperglycemia in diabetic mice. In the present study we tested the hypothesis that BW-HIIT as an effective exercise training modality will decrease cardiometabolic risk with a concomitant decrease in circulating HMGB1 more prominently in insulin resistant individuals compared to non-insulin resistant individuals contrasting to what we can evidence in a preclinical murine model of insulin resistance; Methods: Human and mouse pre- and post-exercise serum/plasma samples were analyzed for Lipidomics as well as Metabolic and Cytokine Multiplex assays. Standard of care, as well as cardiometabolic parameters, was also performed in human subjects; Results: insulin resistant individuals had the most positive effect, primarily with a decrease in the Homeostatic Model Assessment of Insulin Resistance (HOMA-IR). as an index of insulin resistance as well as decreased HMGB1 post-exercise. Lipidomic analysis illustrated the highly beneficial effect of exercise training using a modified HIIT program, showing an enhanced panel of circulating lipids post-exercise exclusively in insulin resistant individuals. Plasma multiplex revealed significant translational heterogeneity in our studies with distinct metabolic hormone responses to exercise conditioning with a decrease in inflammatory markers in insulin resistant individuals; Conclusions: The current study demonstrated that 6-week BW-HIIT training improves cardiometabolic, anti-inflammatory markers, metabolic hormones, and insulin sensitivity in humans, strongly associated with decreased circulating HMGB1. Overall, these experiments reinforce the potential of HMGB1 as a marker of changes in insulin resistance and the positive effect of exercise training on insulin resistance possibly preventing the development of T2D and associated complications.

The Effects of Exercise Training on Functional Capacity and Quality of Life in Patients with Rheumatoid Arthritis: A Systematic Review.

Rheumatoid arthritis (RA) is an autoimmune disease characterized by chronic inflammation. The purpose of this systematic review is to evaluate the effectiveness of exercise training on functional capacity and quality of life (QoL) in patients with RA. We performed a search in four databases, selecting clinical trials that included community or outpatient exercise training programs in patients with RA. The primary outcome was functional capacity assessed by peak VO2 or the 6 min walking test, and the secondary outcome was QoL assessed by questionnaires. Seven studies were finally included, identifying a total number of 448 patients. The results of the present systematic review show a statistically significant increase in peak VO2 after exercise training in four out of seven studies. In fact, the improvement was significantly higher in two out of these four studies compared to the controls. Six out of seven studies provided data on the patients' QoL, with five of them managing to show statistically significant improvement after exercise training, especially in pain, fatigue, vitality, and symptoms of anxiety and depression. This systematic review demonstrates the beneficial effects of exercise training on functional capacity and QoL in patients with RA.

Altered skeletal muscle function and beneficial effects of exercise training in a rat model of induced pulmonary emphysema.

Chronic obstructive pulmonary disease (COPD) is characterized by progressive airflow obstruction and development of emphysema. Among the comorbidities associated with COPD, skeletal muscle dysfunction is known to affect exercise capacity and the survival rate of patients. Pulmonary rehabilitation (PR), via exercise training, is essential for COPD patients. However, the response to PR is most often moderate. An animal model that recapitulates critical features of chronic human disease and provides access to muscle function should therefore be useful to improve PR benefits. We used a rat model of induced emphysema based on pulmonary instillations of elastase (ELA) and lipopolysaccharides (LPS). We assessed the long-term effects of ELA/LPS and the potential effectiveness of endurance training on the skeletal muscle function. Invivo strength of the animals, and exvivo contractility, endurance, type 1 fiber proportion, fiber cross-sectional area, and capillarization of both soleus and extensor digitorum longus (EDL) were assessed. An impaired overall muscle strength with decreased force, reduced capillarization, and atrophy of type 1 fiber of EDL was observed in ELA/LPS rats. Soleus was not affected. Endurance training was able to reduce fatigability, and increase type 1 fiber proportion and capillarization of soleus, and improve force, endurance, and capillarization of EDL in control and ELA/LPS rats. Our rat model of induced emphysema, which shares some features with the phenotype present in patients with COPD, could represent a suitable model to study skeletal muscle dysfunction and the effects of exercise training on muscle function in patients.

Cross-sectional associations between questionnaire-measured physical activity and tissue doppler indices of left ventricular diastolic function

BackgroundThe prevalence of left ventricular (LV) diastolic dysfunction has been increasing over the past decade, and to date, effective pharmacotherapies that enhance LV diastolic function have not yet been identified. Though some data has demonstrated the beneficial effects of exercise training on LV diastolic function, little is known about the adaptations of diastolic function to daily physical activity (PA). Accordingly, our study aimed to investigate the impact of daily PA on tissue Doppler indices of LV diastolic function.MethodsA total of 432 participants were enrolled for clinically indicated echocardiography from July 2019 to July 2020 at Peking University People’s Hospital. Participants aged ≥ 18 years were included if they had stable PA in the past six months and normal LV systolic function. A questionnaire was used to collect demographic characteristics, medical history, and daily PA. According to PA Guidelines for Americans, we identified these participants into low-intensity PA (LPA) group and moderate-high-intensity PA (MHPA) group. Propensity score matching (PSM) was performed to match potential confounding factors between the two groups. The clinical characteristics and echocardiographic parameters between LPA group and MHPA group were compared using student’s t-test, Mann-Whitney U test, and chi-square test as appropriate.ResultsAfter matching potential confounding factors using PSM with a 1:3 matching ratio, our final analysis included 86 cases in the MHPA group and 214 cases in the LPA group. All demographic characteristics and comorbidities were statistically similar between the two groups. Compared to the LPA group, the MHPA group showed higher septal e’ (7.9 ± 2.9 cm/s versus 7.2 ± 2.6 cm/s, P = 0.047). Other echocardiographic parameters associated with LV diastolic function concerning lateral e’ and average E/e’, also trended towards improved LV diastolic function in the MHPA group, but failed to reach statistical significance.ConclusionsOur study demonstrated that moderate-high-intensity daily PA was associated with improved septal e’, suggesting that moderate-high-intensity PA could potentially ameliorate LV diastolic dysfunction.

γ-Aminobutyric acids (GABA) and serum GABA/AABA (G/A) ratio as potential biomarkers of physical performance and aging

Declining physical performance with age and disease is an important indicator of declining health. Biomarkers that identify declining physical performance would be useful in predicting treatment outcomes and identifying potential therapeutics. γ-aminobutyric acid (GABA), a muscle autocrine factor, is a potent inhibitor of muscle function and works as a muscle relaxant. L-α-aminobutyric acid (L-AABA) is a biomarker for malnutrition, liver damage, and depression. We sought to determine if GABA and L-AABA may be useful for predicting physical performance. Serum levels of GABA and L-AABA were quantified in 120 individuals divided by age, sex, and physical capacity into low, average, and high performer groups. Analyses explored correlations between serum levels and physical performance. Both GABA and the ratio of GABA/AABA (G/A), but not AABA, were highly positively associated with age (Pearson correlations r = 0.35, p = 0.0001 for GABA, r = 0.31, p = 0.0007 for G/A, n = 120). GABA showed negative associations in the whole cohort with physical performance [fast gait speed, 6 min walk test (6MWT), PROMIS score, and SF36PFS raw score] and with subtotal and femoral neck bone mineral density. L-AABA was positively associated with usual gait speed, 6MWT, total SPPB score, and SF36PFS raw score in the total cohort of 120 human subjects, also with 6MWT and SF36PFS raw score in the 60 male subjects, but no associations were observed in the 60 females. As both GABA and L-AABA appear to be indicative of physical performance, but in opposite directions, we examined the G/A ratio. Unlike GABA, the G/A ratio showed a more distinct association with mobility tests such as total SPPB score, usual and fast gait speed, 6MWT, and SF36PFS raw score in the males, regardless of age and metabolic status. Serum G/A ratio could be potentially linked to physical performance in the male population. Our findings strongly suggest that GABA, L-AABA, and the G/A ratio in human serum may be useful markers for both age and physical function. These new biomarkers may significantly enhance the goal of identifying universal biomarkers to accurately predict physical performance and the beneficial effects of exercise training for older adults.

NOX2 deficiency exacerbates diet-induced obesity and impairs molecular training adaptations in skeletal muscle

The production of reactive oxygen species (ROS) by NADPH oxidase (NOX) 2 has been linked to both insulin resistance and exercise training adaptations in skeletal muscle. This study explores the previously unexamined role of NOX2 in the interplay between diet-induced insulin resistance and exercise training (ET). Using a mouse model that harbors a point mutation in the essential NOX2 regulatory subunit, p47phox (Ncf1*), we investigated the impact of this mutation on various metabolic adaptations. Wild-type (WT) and Ncf1* mice were assigned to three groups: chow diet, 60% energy fat diet (HFD), and HFD with access to running wheels (HFD + E). After a 16-week intervention, a comprehensive phenotypic assessment was performed, including body composition, glucose tolerance, energy intake, muscle insulin signaling, redox-related proteins, and mitochondrial adaptations. The results revealed that NOX2 deficiency exacerbated the impact of HFD on body weight, body composition, and glucose intolerance. Moreover, in Ncf1* mice, ET did not improve glucose tolerance or increase muscle cross-sectional area. ET normalized body fat independently of genotype. The lack of NOX2 activity during ET reduced several metabolic adaptations in skeletal muscle, including insulin signaling and expression of Hexokinase II and oxidative phosphorylation complexes. In conclusion, these findings suggest that NOX2 mediates key beneficial effects of exercise training in the context of diet-induced obesity.

Exercise Is Medicine: How Do We Implement It?

Exercise is well known to have beneficial effects on various disease states. In this paper, we broadly describe the fundamental concepts that are shared among various disease states, including obesity, type 2 diabetes (T2D), cardiovascular disease (CVD), heart failure (HF), cancer, and psychological well-being, and the beneficial effects of exercise training within these concepts. We highlight issues involved in implementing exercise recommendations and describe the potential impacts and challenges to medical professionals and patients. Problems are identified and discussed with respect to the future roles of professionals in the current built environment with its limited infrastructure to support current physical activity recommendations.

Physical Activity Protocols in Non-Alcoholic Fatty Liver Disease Management: A Systematic Review of Randomized Clinical Trials and Animal Models.

Non-alcoholic fatty liver disease (NAFLD) is closely associated with other metabolic disease and cardiovascular disease. Regular exercise reduces hepatic fat content and could be the first-line treatment in the management of NAFLD. This review aims to summarize the current evidence of the beneficial effects of exercise training and identify the molecular pathways involved in the response to exercise to define their role in the resolution of NAFLD both in animal and human studies. According to the inclusion criteria, 43 animal studies and 14 RCTs were included in this systematic review. Several exercise modalities were demonstrated to have a positive effect on liver function. Physical activity showed a strong association with improvement in inflammation, and reduction in steatohepatitis and fibrosis in experimental models. Furthermore, both aerobic and resistance exercise in human studies were demonstrated to reduce liver fat, and to improve insulin resistance and blood lipids, regardless of weight loss, although aerobic exercises may be more effective. Resistance exercise is more feasible for patients with NAFLD with poor cardiorespiratory fitness. More effort and awareness should be dedicated to encouraging NAFLD patients to adopt an active lifestyle and benefit from it its effects in order to reduce this growing public health problem.

The efficacy of high- and low-load resistance training in patients with coronary artery disease: a follow-up of a randomised controlled trial

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Slovenian Research Agency. Background Perseverance of beneficial effects of exercise training in cardiac rehabilitation remains understudied. Maximal aerobic capacity (VO2 max) and quality life were mostly maintained at 1 year follow-up after aerobic training (AT) or after a combination of AT and mostly low-load (LL) resistance training (RT), while the effects of high-load (HL) RT remain unknown in patients with coronary artery disease (CAD). Purpose This study investigated the effects of combination of AT with HL-RT or LL-RT in comparison to AT alone on maximal aerobic capacity, physical activity, and quality of life in patients with CAD at 1-year follow-up after cardiac rehabilitation. Methods We initially enrolled 79 patients with CAD to combined AT and HL-RT, combined AT and LL-RT or AT alone, and 59 patients completed the study. The assessments at 1-year follow-up were completed by 53 patients, with [mean (SD) or median (interquartile range)] age = 61 (8) years, height = 172.1 (8.4) cm, weight = 83.93 (14.03) kg and left ventricular ejection fraction = 50 (45,60) %. During the study, all patients performed the same interval aerobic cycling (40 min/session, intervals of 3-5 min of work-load cycling separated by 2 min of unloaded cycling, intensity progressed from 50% to 80% of maximal workload achieved at baseline cardiopulmonary exercise test). In HL-RT-group, the training load progressively increased from 70% of 1-RM (6–11 reps/set) to 80% of 1-RM (6–8 reps/set), while in LL-RT group the training load progressively increased from 35% of 1-RM (12–22 reps/set) to 40% of 1-RM (12–16 reps/set) in the first seven weeks of the intervention. Similar progression of RT was used after 1-RM re-evaluation following 7 weeks of training. After cardiac rehabilitation, patients were given written brochure with included advice on home-based physical activity with emphasis on aerobic and resistance exercises. Maximal aerobic performance, objectively measured physical activity and quality of life were measured after 1-year. Results At 1-year follow-up majority of the patients increased VO2max (62%). Patients increased VO2max (+0.08 l/min, p = 0.022) and had higher respiratory exchange ratio (+0.06, p < 0.001), regardless of the randomisation. There was no significant effect of time x group interaction on the outcomes. VO2max was increased in AT (+0.13 l/min, p = 0.026) and LL-RT (+0.12 l/min, p = 0.031) groups, while respiratory exchange ratio was greater in LL-RT (+0.6, p = 0.004) and HL-RT (+0.7, p = 0.003) groups at follow-up. Post-training physical activity and quality of life were high but remained unchanged after 1 year. Conclusions The combination of AT and HL-RT or LL-RT was not superior to AT alone in changes of maximal aerobic performance, physical activity and quality of life in patients with coronary artery disease at 1-year follow-up.

Thermoneutral housing increases the obesogenic phenotype of mice, while some effects of exercise are reduced

Introduction: Mice are extensively used to investigate the molecular foundations of obesity and the beneficial effect of exercise training (ET). Mice are most often housed at ambient temperature, ~22°C, which is below their thermoneutral environment (~30°C). Mild cold stress at ambient temperature accelerates mouse metabolic rate and may confound translation of results to humans. Aiming to determine the metabolic adaptations of ET in an obesogenic environment, we hypothesized that thermoneutral housing would increase adiposity during high-fat feeding. Moreover, thermoneutral housing would blunt the effects of ET by relieving the added cold stress. Methods: After temperature acclimatization (3 weeks, 22°C vs. 30°C), C57BL/6J mice (n=68, ♀, Age: 11 weeks) were dual-housed for 8 weeks receiving a chow diet or a 60%E high-fat diet (HFD). HFD mice were then separated into two additional groups with access to voluntary wheel running for another 8 weeks. Metabolic parameters were measured using magnetic resonance imaging, indirect calorimetry, glucose tolerance tests, and maximal running capacity on treadmill. Brown and white adipose tissues and gastrocnemius muscle mRNA and protein content were analyzed using qPCR and immunoblotting analyses, respectively. Results: In chow-fed mice, thermoneutral housing decreased metabolic rate (VO2), fasting plasma glucose, and thermogenic genes in adipose tissue depots, without changes in skeletal muscle mitochondrial protein content compared to 22°C. In HFD mice, thermoneutral housing increased fat mass, induced glucose intolerance, and fasting plasma insulin levels compared to 22°C housing. This was despite decreased food intake and metabolic rate compared to HFD mice housed at 22°C. ET mice improved the exercise capacity and glucose tolerance independent of housing temperature. Interestingly, while ET at 30°C prevented further fat gain during the intervention, ET at 22°C decreased fat mass. Moreover, only ET at 22°C increased the metabolic rate during the active phase. Gene expression responded similarly to ET independent of housing temperature in adipose tissue depots. ET induced GLUT4, peroxiredoxin 2 and pyruvate dehydrogenase protein content to a lesser extent in muscle at 30°C housing. Conclusion: Adaptations to diet-induced obesity and ET in mice critically depend upon housing temperature. Our findings underscore housing temperature as a key consideration in research related the beneficial effect of exercise in an obesogenic environment. Disclosure of funding: SHR is supported by the Lundbeck Foundation and Independent Research Fund Denmark. LS and EAR are supported by the Novo Nordisk Foundation and Independent Research Fund Denmark. IK is supported by the Novo Nordisk Foundation. This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Exercise training remodels inguinal white adipose tissue through adaptations in innervation, vascularization, and the extracellular matrix

Inguinal white adipose tissue (iWAT) is essential for the beneficial effects of exercise training on metabolic health. The underlying mechanisms for these effects are not fully understood, and here, we test the hypothesis that exercise training results in a more favorable iWAT structural phenotype. Using biochemical, imaging, and multi-omics analyses, we find that 11days of wheel running in male mice causes profound iWAT remodeling including decreased extracellular matrix (ECM) deposition and increased vascularization and innervation. We identify adipose stem cells as one of the main contributors to training-induced ECM remodeling, show that the PRDM16 transcriptional complex is necessary for iWAT remodeling and beiging, and discover neuronal growth regulator 1 (NEGR1) as a link between PRDM16 and neuritogenesis. Moreover, we find that training causes a shift from hypertrophic to insulin-sensitive adipocyte subpopulations. Exercise training leads to remarkable adaptations to iWAT structure and cell-type composition that can confer beneficial changes in tissue metabolism.

Neurocirculatory regulation and adaptations to exercise in chronic kidney disease.

Chronic kidney disease (CKD) is characterized by pronounced exercise intolerance and exaggerated blood pressure reactivity during exercise. Classic mechanisms of exercise intolerance in CKD have been extensively described previously and include uremic myopathy, chronic inflammation, malnutrition, and anemia. We contend that these classic mechanisms only partially explain the exercise intolerance experienced in CKD and that alterations in cardiovascular and autonomic regulation also play a key contributing role. The purpose of this review is to examine the physiological factors that contribute to neurocirculatory dysregulation during exercise and discuss the adaptations that result from regular exercise training in CKD. Key neurocirculatory mechanisms contributing to exercise intolerance in CKD include augmentation of the exercise pressor reflex, aberrations in neurocirculatory control, and increased neurovascular transduction. In addition, we highlight how some contributing factors may be improved through exercise training, with a specific focus on the sympathetic nervous system. Important areas for future work include understanding how the exercise prescription may best be optimized in CKD and how the beneficial effects of exercise training may extend to the brain.

Effects of Aerobic Exercise on Cardiorespiratory Fitness, Cardiovascular Risk Factors, and Patient-Reported Outcomes in Long-Term Breast Cancer Survivors: Protocol for a Randomized Controlled Trial.

Anthracycline-based chemotherapy has been mainstay of adjuvant breast cancer therapy for decades. Although effective, anthracyclines place long-term breast cancer survivors at risk of late effects, such as reduced cardiorespiratory fitness and increased risk of cardiovascular disease. Previous research has shown beneficial effects of exercise training on cardiorespiratory fitness, but the effects of exercise on limiting factors for cardiorespiratory fitness, cardiovascular risk factors, and patient-reported outcomes in long-term survivors are less clear. Whether previous exposure to breast cancer therapy modulates the effects of exercise is also unknown. The primary aim of the CAUSE (Cardiovascular Survivors Exercise) trial is to examine the effect of aerobic exercise on cardiorespiratory fitness in anthracycline-treated long-term breast cancer survivors. Secondary aims are to examine effects of exercise training on limiting factors for cardiorespiratory fitness, cardiovascular risk factors, and patient-reported outcomes, and to compare baseline values and effects of exercise training between similar-aged women with and those without prior breast cancer. A third aim is to examine the 24-month postintervention effects of aerobic exercise on primary and secondary outcomes. The CAUSE trial is a 2-armed randomized controlled trial, where 140 long-term breast cancer survivors, 8-12 years post diagnosis, are assigned to a 5-month nonlinear aerobic exercise program with 3 weekly sessions or to standard care. Seventy similar-aged women with no history of cancer will undergo the same exercise program. Cardiorespiratory fitness measured as peak oxygen consumption (VO2peak), limiting factors for VO2peak (eg, cardiac function, pulmonary function, hemoglobin mass, blood volume, and skeletal muscle characteristics), cardiovascular risk factors (eg, hypertension, diabetes, dyslipidemia, obesity, physical activity level, and smoking status), and patient-reported outcomes (eg, body image, fatigue, mental health, and health-related quality of life) will be assessed at baseline, post intervention, and 24 months post intervention. A total of 209 patients were included from October 2020 to August 2022, and postintervention assessments were completed in January 2023. The 24-month follow-up will be completed in February 2025. The findings from the CAUSE trial will provide novel scientific understanding of the potential benefits of exercise training in long-term breast cancer survivors. ClinicalTrials.gov NCT04307407; https://clinicaltrials.gov/ct2/show/NCT04307407. DERR1-10.2196/45244.

FNDC5/Irisin Inhibits the Inflammatory Response and Mediates the Aerobic Exercise-Induced Improvement of Liver Injury after Myocardial Infarction

Myocardial infarction (MI) causes peripheral organ injury, in addition to cardiac dysfunction, including in the liver, which is known as cardiac hepatopathy. Aerobic exercise (AE) can effectively improve liver injury, although the mechanism and targets are currently not well established. Irisin, mainly produced by cleavage of the fibronectin type III domain-containing protein 5 (FNDC5), is a responsible for the beneficial effects of exercise training. In this study, we detected the effect of AE on MI-induced liver injury and explored the role of irisin alongside the benefits of AE. Wildtype and Fndc5 knockout mice were used to establish an MI model and subjected to AE intervention. Primary mouse hepatocytes were treated with lipopolysaccharide (LPS), rhirisin, and a phosphoinositide 3-kinase (PI3K) inhibitor. The results showed that AE significantly promoted M2 polarization of macrophages and improved MI-induced inflammation, upregulated endogenous irisin protein expression and activated the PI3K/ protein kinase B (Akt) signaling pathway in the liver of MI mice, while knockout of Fndc5 attenuated the beneficial effects of AE. Exogenous rhirisin significantly inhibited the LPS-induced inflammatory response, which was attenuated by the PI3K inhibitor. These results suggest that AE could effectively activate the FNDC5/irisin-PI3K/Akt signaling pathway, promote the polarization of M2 macrophages, and inhibit the inflammatory response of the liver after MI.

The Therapeutic Role of Exercise Training in Heart Failure Patients: A Narrative Review

Cardiac rehabilitation (CR) is a complex intervention that improves functional capacity and quality of life in patients with heart failure (HF). Besides exercise training (ET), CR includes aggressive risk factor management, education about medication adherence, stress management, and psychological support. Current guidelines strongly recommend CR as an integral part of chronic and stable HF patient care. However, CR programs are underused for multiple reasons, namely, low physician referral and patient adherence, high cost, and lack of awareness. In this review, we present existing evidence of the beneficial effects of ET and CR in HF with reduced and preserved ejection fraction, the underlying pathophysiologic mechanisms by which exercise might alleviate symptoms, and the different types of exercise that can be used in HF. Current guidelines supporting the use of CR, reasons for its underutilization, and home-based CR as an alternative or adjunct to traditional center-based programs are also described.

Abstract C109: Testing Home-based Exercise Strategies in Underserved Minority Cancer Patients Undergoing Chemotherapy (THRIVE) Trial: A study protocol

Abstract Background: Higher rates of physical inactivity and comorbid conditions are reported in Hispanic and Black cancer patients receiving chemotherapy, compared to their White counterparts. Despite the beneficial effect of exercise training for cancer patients, rates of participation in clinical cancer trials are low among disadvantaged and racial and ethnic minority groups. This is possibly due to more barriers and less access to exercise training. Therefore, there is a crucial need for better understanding of how to apply exercise interventions using novel, accessible, and cost-effective home-based exercise approaches for Hispanic and Black communities, particularly during chemotherapy. In this study, we will examine the effect of supervised and unsupervised exercise on minutes of physical activity among Hispanic and Black cancer patients undergoing chemotherapy for breast, colorectal, and prostate cancer. Methods: The THRIVE trial is an 8-month prospective, three-arm study of 135 patients who are randomized in a 1:1:1 fashion to a supervised exercise intervention (SUP), unsupervised exercise (UNSUP), or an attention control group. Eligible patients include those with early-stage breast, colorectal, or prostate cancer, planning to receive chemotherapy, are sedentary, overweight or obese, and self-identifying as Hispanic or Black. Patients randomized to the SUP group participate in a home-based 16-week periodized aerobic and resistance exercise program performed three days per week, supervised through video conference technology. Patients randomized to the UNSUP group participate in an unsupervised 16-week, telehealth-based, periodized aerobic and resistance exercise program performed three days per week using the same exercise prescription parameters as the SUP group. The attention control group receive a 16-week home-based stretching program. The primary outcome is changes in minutes of physical activity assessed by 7-day accelerometry at month 4. Secondary outcomes include cardiovascular risk factors, patient-reported outcomes, and physical function. Outcome measures are tested at baseline, post-intervention at month 4, and after a non-intervention follow-up period at month 8. Discussion: The THRIVE trial is the first study to employ a novel and potentially achievable exercise intervention for a minority population receiving chemotherapy. In addition, this study utilizes an intervention approach to investigate the biological and behavioral mechanisms underlying exercise participation in these cancer patients. Results from this study will guide and inform large randomized controlled trials to test the effect of home-based exercise on treatment outcomes and comorbid disease risk in minority patients with cancer undergoing chemotherapy. Citation Format: Huimin Yan, Noelle Merchant, Ashley Desameau, Cherardi NeiraViscue, Paola Gonzalo-Encabo, Dong-Woo Kang, Rebekah L. Wilson, Mary K. Norris, Danny Nguyen, Daniel Gundersen, Laura L. Hayman, Rachel A. Freedman, Timothy Rebbeck, Christina M. Dieli-Conwright. Testing Home-based Exercise Strategies in Underserved Minority Cancer Patients Undergoing Chemotherapy (THRIVE) Trial: A study protocol [abstract]. In: Proceedings of the 15th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2022 Sep 16-19; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2022;31(1 Suppl):Abstract nr C109.

Exercise Training as a Non-Pharmacological Therapy for Patients with Pulmonary Arterial Hypertension: Home-Based Rehabilitation Program and Training Recommendations.

Pulmonary arterial hypertension (PAH) is a chronic and progressive disorder with a poor prognosis associated with non-specific symptoms, including general weakness, shortness of breath on exertion, and decreased muscle strength and endurance. Despite recent significant progress in the field of PAH therapy, many patients are still characterized by a dynamic course of the disease, a significant reduction in physical performance, a constantly deteriorating quality of life, and limited activity in everyday life. Thus, the main goal of PAH therapy is to ensure an acceptable level of quality of life as early as possible in the course of the disease, reduce the progression of symptoms and, if possible, improve the prognosis, which is still poor. The perception of the importance of activity and exercise has changed significantly in recent years, and rehabilitation dedicated to PAH patients is now considered to be one of the new adjuvant treatment options. Currently, there is insufficient data on what form, frequency, and intensity of exercise are required for the best results. Nevertheless, exercise training (ET) is necessary in order to reverse the accompanying PAH impairment of exercise capacity and, without additional clinical risk, to maximize the benefits of pharmacotherapy. This review summarizes the current state of knowledge on the rehabilitation of PAH patients and presents the available rehabilitation models. In addition, it includes a ready-to-use, illustrated, safe home rehabilitation program with recommendations for its use. Utilizing ET as an adjuvant treatment option to improve the functional capacity and quality of life of patients may enhance the clinical effectiveness of therapeutic management and contribute to the improvement of the quality of care for patients suffering from PAH. The beneficial effect of exercise training on the development of symptoms improves the clinical course of the disease, and a lower incidence of adverse events can lead to a reduction in health care expenditure.