Effects Of Long-term Exercise Training Research Articles

Spatiotemporal analysis of the effects of exercise on the hemodynamics of the aorta in hypertensive rats using fluid-structure interaction simulation

Abstract Background and Objective Hemodynamic changes that lead to increased blood pressure represent the main drivers of organ damage in hypertension. Prolonged increases to blood pressure can lead to vascular remodeling, which also affects vascular hemodynamics during the pathogenesis of hypertension. Exercise is beneficial for relieving hypertension, however the mechanistic link between exercise training and how it influences hemodynamics in the context of hypertension is not well understood. Methods n exercise model was developed using spontaneously hypertensive rats (SHR) subject to a 12-week treadmill training regime. The heart rates and blood pressures of rats were measured using the tail cuff method, while micro-computed tomography (CT) scanning was used to develop three-dimensional structures of rat aorta, and ultrasound was used to detect rat aortic blood flow and changes to vessel wall structures. Computational fluid dynamics (CFD) and fluid-structure interaction (FSI) models were used to simulate and measure hemodynamic parameters of the rat aortic vessels. In parallel, Masson staining was performed on fixed samples of blood vessels to investigate collagen volume fraction. Hypertensive rats in the sedentary and long-term exercise training groups were subjected to a single bout exercise training, and their aortic hemodynamic parameters were analyzed before, 5 min, 24 h, and 72 h after the single bout exercise. Results Of the two models, in comparison to actual ultrasonic measurement values recorded, we found that numerical simulation results from the FSI model could more accurately model blood flow in the ascending aorta of hypertensive rats, compared to the CFD model. Moreover, longterm exercise training improved local hemodynamic parameters of blood vessels, and led to improvements in adverse hemodynamic features documented, including time-averaged wall shear stress (TAWSS), oscillatory shear index (OSI), and relative residence time (RRT). Longterm exercise training of SHR also improved local vascular collagen deposition in the aorta, while improvements in vascular remodeling were also correlated with favorable hemodynamic parameters. Compared with sedentary SHR, signals for low TAWSS regions of the aortic arch in SHR on the long-term exercise regime shifted to the position of the ascending aorta after a single bout of exercise. Conclusions This study demonstrates that FSI is informative to study the spatiotemporal effects of long-term exercise training on hemodynamic changes within the aortas of hypertensive rats, and that long-term exercise is beneficial through its effects to modulate vascular hemodynamics in hypertension.

Effect of Long-term Exercise Training on the Endothelial Function in Patients with Atrial Fibrillation: A Randomized Trial.

Effect of Long-term Exercise Training on the Endothelial Function in Patients with Atrial Fibrillation: A Randomized Trial.

Long-term exercise training and inflammatory biomarkers in healthy subjects: a meta-analysis of randomized controlled trials.

This meta-analysis investigated the effect of long-term exercise training (ET) including aerobic, resistance, and multicomponent ET on the levels of inflammatory biomarkers in randomized controlled trials (RCTs) involving healthy subjects. We searched seven databases for articles until May 1st, 2023. A random-effect meta-analysis, subgroup analysis, meta-regressions as well as trim and fill method were conducted using STATA 16.0. Thirty-eight studies were included in the meta-analysis, involving 2,557 healthy subjects (mean age varies from 21 to 86 years). Long-term ET induced significantly decreased in the levels of interleukin-6 (IL-6) (SMD -0.16, 95% CI -0.30 to -0.03, p = 0.017), C-reactive protein (CRP) (SMD -0.18, 95% CI -0.31 to -0.06, p = 0.005), as well as tumor necrosis factor alpha (TNFα) (SMD -0.43, 95% CI -0.62 to -0.24, p < 0.001). Subgroup analysis revealed that Long-term ET conducted for more than 12 weeks and exercise of moderate intensity had greater anti-inflammatory effects. Meta-regression analysis showed that the reduction in CRP level induced by long-term ET was weakened by increasing exercise intensity. Long-term ET induced significant anti-inflammatory effects in healthy subjects. Long-term ET-induced anti-inflammatory effects were associated with exercise of moderate intensity and training conducted for more than 12 weeks.Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/# myprospero, PROSPERO, identifier CRD42022346693.

Effects of long-term exercise training on physiological signals and personality traits in women in law enforcement

Law enforcement teams across the globe experience the highest occupational stress and stress-related diseases. Physical exercise and an active lifestyle are recommended as part of their profession to equip them to fight stress and related health adversities. The research is carried out using objective measures of Heart Rate Variability (HRV), Electro Dermal Activity (EDA), Heart Rate Recovery (HRR), and subjective questionnaires. HRV was generated with an electrocardiogram (ECG) signal acquired using NI myRIO 1900 interfaced with the Vernier EKG sensor. HRR was acquired with the help of a Polar chest strap exercise heart rate monitor and EDA acquisition was carried out with Mindfield E-Sense electrodes. Then statistical features are extracted from the collected data, and feed to the AQCNN (Aquila convolution neural network) classifier to predict the stress. Signal analyses were done in Kubios 4.0, Ledalab V3.x in a MATLAB environment. The results pointed out that exercise training is effective in increasing the vagal tone of the Autonomic Nervous System (ANS) and hence improves the recovery potential of the cardiovascular system from stress. The proposed AQCNN method improves the accuracy by 95.12% which is better than 93.13%, 85.36% and 80.13% from Statistical technique, CNN and ML-SVM respectively. The findings have the potential to influence decision-making in the selection and training of recruits in high-stress positions, hence optimizing the cost and time of training by identifying maladaptive recruits early.

Effect of Long-term Exercise Training on Physical Performance and Cardiorespiratory Function in Adults With CKD: A Randomized Controlled Trial

The safety and efficacy of long-term exercise training in reducing physical functional loss in older adults with advanced CKD and comorbidity is uncertain. Multicenter, parallel group, randomized controlled trial. Adults 55 years and older with estimated glomerular filtration rate (eGFR) of 15 to<45 mL/min/1.73 m2 enrolled from centers in Baltimore and Boston. Twelve months of in-center supervised exercise training incorporating majority aerobic but also muscle strengthening activities or a group health education control intervention, randomly assigned in 1:1 ratio. Primary outcomes were cardiorespiratory fitness and submaximal gait at 6 and 12 months quantified by peak oxygen consumption (Vo2peak) on graded exercise treadmill test and distance walked on the 6-minute walk test, respectively. Secondary outcomes were changes in lower extremity function, eGFR, albuminuria, glycemia, blood pressure, and body mass index. Among 99 participants, the mean age was 68 years, 62% were African American, and the mean eGFR was 33 mL/min/1.73 m2; 59% had diabetes, and 29% had coronary artery disease. Among those randomized to exercise, 59% of exercise sessions were attended in the initial 6 months. Exercise was well tolerated without excess occurrence of adverse events. At 6 months, aerobic capacity was higher among exercise participants (17.9 ± 5.5 vs 15.9 ± 7.0 mL/kg/min, P= 0.03), but the differences were not sustained at 12 months. The 6-minute walk distance improved more in the exercise group (adjusted difference: 98 feet [P= 0.02; P= 0.03 for treatment-by-time interaction]). The exercise group had greater improvements on the Timed Up and Go Test (P= 0.04) but not the Short Physical Performance Battery (P= 0.8). Planned sample size was not reached. Loss to follow-up and dropout were greater than anticipated. Among adults aged≥55 years with CKD stages 3b-4 and a high level of medical comorbidity, a 12-month program of in-center aerobic and resistance exercise training was safe and associated with improvements in physical functioning. Government grants (National Institutes of Health). Registered at ClinicalTrials.gov with study number NCT01462097.

EFFECT OF SPORTS TRAINING ON THE REHABILITATION OF HYPERTENSIVE PATIENTS

ABSTRACT Introduction: Hypertension is one of the most common cardiovascular and cerebrovascular diseases and a major public health problem. Although, through the rational use of drugs, the blood pressure of hypertensive patients can be better controlled, a series of side effects of drugs and expensive medical expenses limit the ability of patients to comply with the demands of hypertension. Objective: To explore the effect of long-term exercise training on the rehabilitation of hypertensive patients. Methods: The patients were divided into a control group and an exercise group, and we used multiple measurements of blood pressure, a questionnaire, and registered the situation of each patient, after what results were compared and analyzed. Results: After 12 weeks of training, the subject's blood pressure has dropped significantly. The systolic blood pressure dropped by an average of 15.5mmHg compared to before the exercise prescription was implemented, diastolic blood pressure dropped by an average of 10.6mmHg. Conclusions: Continuous physical exercise in hypertensive patients has medium- and long-term effect on blood pressure control. Level of evidence II; Therapeutic studies - investigation of treatment results.

Effects of Circuit Training Program on Cardiovascular Risk Factors, Vascular Inflammatory Markers, and Insulin-like Growth Factor-1 in Elderly Obese Women with Sarcopenia.

Sarcopenic obesity is caused by a decrease in muscle mass and an increase in body fat due to aging, and has been the cause of cardiovascular diseases such as hypertension, diabetes, hyperlipidemia, and arteriosclerosis and high inflammatory conditions. However, there is a lack of research on the effects of long-term exercise training as regards to the body composition and blood-related physiological indicators. Therefore, the purpose of this study was to investigate the influences the effect of circuit exercise training for 12 weeks on cardiovascular risk factors, vascular inflammatory markers, and insulin-like growth factor-1 (IGF-1) in elderly obesity women with sarcopenia. A total of 28 elderly obese Korean women with sarcopenia (75.0 5.1 years) were randomly assigned either to a control group (CG, n = 14) or an exercise group (EG, n = 14). The EG performed circuit exercise training for 25-75 minutes (gradually incremental) three times per week over a period of 12 weeks, while the CG maintained their usual daily lifestyle during the intervention period. Pre- and post-intervention evaluations were performed on selected cardiovascular risk factors, inflammatory markers, and IGF-1. The EG group exhibited improved body composition (i.e., body mass index, fat-free mass, % fat mass, waist-to-hip ratio; all p 0.030, 2 0.169), Cardiovascular risks factor (i.e., heart rate, systolic blood pressure, rate pressure product, high-density lipoprotein cholesterol, total cholesterol/HDL-C ratio, triglyceride/HDL-C ratio, low-density lipoprotein cholesterol/HDL-C ratio, brachial-ankle pulse wave velocity, fasting plasma insulin, homeostasis model assessment-insulin resistance; all p 0.042, 2 0.150), Inflammatory markers (i.e., high sensitivity C-reactive protein, interleukin-6; all p 0.045, 2 0.146), and IGF-1 (p = 0.037, 2 = 0.157). Conversely, there were no significant changes observed in CG. Twelve weeks of circuit training had a positive effect on the improvement in cardiovascular risk factors, vascular inflammatory markers, and IGF-1 in elderly obese women with sarcopenia.

Long-Term Endurance Exercise Training Alters Repolarization in a New Rabbit Athlete's Heart Model.

In the present study, the effect of long-term exercise training was investigated on myocardial morphological and functional remodeling and on proarrhythmic sensitivity in a rabbit athlete’s heart model. New-Zealand white rabbits were trained during a 12-week long treadmill running protocol and compared with their sedentary controls. At the end of the training protocol, echocardiography, in vivo and in vitro ECG recordings, proarrhythmic sensitivity with dofetilide (nM) were performed in isolated hearts, and action potential duration (APD) measurements at different potassium concentrations (4.5 and 2 mM) were made in the isolated papillary muscles. Expression levels of the slow component of delayed rectifier potassium current and fibrosis synthesis and degradation biomarkers were quantified. Echocardiography showed a significantly dilated left ventricle in the running rabbits. ECG PQ and RR intervals were significantly longer in the exercised group (79 ± 2 vs. 69 ± 2 ms and 325 ± 11 vs. 265 ± 6 ms, p < 0.05, respectively). The in vivo heart rate variability (HRV) (SD of root mean square: 5.2 ± 1.4 ms vs. 1.4 ± 0.2 ms, p < 0.05) and Tpeak-Tend variability were higher in the running rabbits. Bradycardia disappeared in the exercised group in vitro. Dofetilide tended to increase the QTc interval in a greater extent, and significantly increased the number of arrhythmic beats in the trained animals in vitro. APD was longer in the exercised group at a low potassium level. Real-time quantitative PCR (RT-qPCR) showed significantly greater messenger RNA expression of fibrotic biomarkers in the exercised group. Increased repolarization variability and higher arrhythmia incidences, lengthened APD at a low potassium level, increased fibrotic biomarker gene expressions may indicate higher sensitivity of the rabbit “athlete’s heart” to life-threatening arrhythmias.

Adiponectin in relation to exercise and physical performance in patients with type 2 diabetes and coronary artery disease

ABSTRACT Introduction: Adipokines, expressed by adipose tissue (AT), have been associated with metabolic disturbances and coronary artery disease (CAD). The impact of exercise training on the AT in patients suffering from both diabetes and CAD is unknown. To gain knowledge on changes in ATs’ inflammatory profile in such a population, we investigated the effects of long-term exercise on selected adipokines and their associations with physical performance and glucometabolic variables. Adiponectin was selected based on its anti-atherogenic and anti-diabetic properties and visfatin and tumour necrosis factor (TNF) for their association with atherosclerosis and metabolic disorders. Not many studies have focused on the effects of long-term exercise training on adipokines in patients with concomitant T2DM and CAD. Methods: Patients with type 2 diabetes and CAD (n = 137), 41–81 years, 17.2% females, were randomized in a 1:1 manner to an exercise group, who underwent 1 year of 150 min weekly combined strength and endurance exercise, or a control group. AT from the gluteal region and blood samples were obtained at baseline and after 12 months, along with a physical performance test, assessed by the VO2 peak. Circulating protein levels were measured by ELISA. RNA was extracted from AT and expression levels were relatively quantified by PCR. Results: After 1 year, no significant difference in the change in the investigated markers between the intervention group and the control group was observed. Changes in circulating adiponectin and VO2 peak correlated in the total population (r = 0.256, p = 0.008). At baseline, circulating adiponectin and TNF correlated inversely with insulin and with C-peptide and VO2peak, respectively (p < 0.001, all). Conclusion: In this population with concomitant diabetes and CAD, ATs’ inflammatory profile remained unchanged apparently after 1 year of exercise intervention. Changes in the VO2peak were nevertheless, related to changes in circulating adiponectin levels. Trial registration: http://www.clinicaltrials.gov NCT01232608.

Effect of long-term exercise training on markers of gut leakage in patients with CAD and type 2 diabetes: A sub-study of a randomized controlled trial

Effect of long-term exercise training on markers of gut leakage in patients with CAD and type 2 diabetes: A sub-study of a randomized controlled trial

Effect of long-term exercise training on static postural control in older adults: a cross-sectional study

ABSTRACT We examined the effects of long-term exercise on age-related decline in static balance control through centre-of-pressure (CoP) measurements of four groups of participants: older controls, younger controls, older Tai Chi exercisers and older joggers. The participants stood quietly in a tandem stance on a force platform for 30 s with eyes open (EO) and eyes closed (EC). The older controls showed remarkably larger CoP and EC/EO ratios than younger controls and older Tai Chi exercisers. The EC/EO ratios of velocity in the mediolateral direction of older joggers were significantly smaller than those of older controls. Results suggest that the static balance of older controls showed a significant decline caused by age-related changes. Long-term Tai Chi and jogging, particularly the former, contributed to static balance control in older people. Older adults relied more on visual information in static postural control than young people. Tai Chi would be an ideal exercise for improving static balance in older people.

Effects of long-term exercise training for different durations on pancreatic amylase activity and intestinal glucose transporter content in rats.

Long‐term endurance training for a relatively short duration (~1 h) is reported to increase pancreatic amylase activity in rats, suggesting that chronic exercise training enhances carbohydrate digestive capacity. However, it remains unknown whether longer exercise training duration results in greater adaptation in the pancreas and small intestine. Thus, this study aimed to examine the effects of long‐term endurance training for a longer duration on pancreatic amylase activity and intestinal glucose transporter content in rats. Male Sprague–Dawley rats were subjected to swimming exercise training for 1 h (Ex‐1h group) or 6 h (Ex‐6h group, two 3‐h sessions separated by 1 h of rest) each day, 5 days a week, for 6 weeks. Sedentary rats were used as a control (Con group). Total pancreatic amylase activity in the Ex‐6h group was significantly lower than that in the Con and Ex‐1h groups immediately after the last training session. After 24 h of recovery, total pancreatic amylase activity was significantly higher in the Ex‐1h group (~46%) than in the Con group, and a further increase was observed in the Ex‐6h group (~98%). In addition, the Ex‐6h group, but not the Ex‐1h group, showed significantly greater intestinal sodium‐dependent glucose transporter 1 (SGLT1) content compared with the Con group after 24 h of recovery. However, no significant difference was observed in glucose transporter 2 (GLUT2) content among the three groups. In conclusion, chronic endurance exercise training for a longer duration results in larger increases in pancreatic amylase activity and intestinal SGLT1 content in rats.

Effects of exercise training on inflammasome-related mediators and their associations to glucometabolic variables in patients with combined coronary artery disease and type 2 diabetes mellitus: Sub-study of a randomized control trial.

Adipose tissue produces pro-inflammatory mediators involved in the atherosclerotic process. We investigated whether 12-month exercise training in patients with type 2 diabetes mellitus and coronary artery disease would reduce circulating levels and genetic expression of mediators in the interleukin-18, Caspase-1 and NLR pyrin domain containing 3 pathways. Correlations to glucometabolic variables; fasting glucose, HbA1c, duration of diabetes, insulin, C-peptide, insulin resistance (measured by homeostatic model assessment indexes - insulin resistance) and body mass index at baseline were further assessed. 137 patients (aged 41-81 years, 17.2% female participants) were included and randomized to a 12-month exercise programme or to a control group. Fasting blood and adipose tissue samples were taken at inclusion and after 12 months. No statistically significant difference in changes of any variable between the intervention and the control group was found. At baseline, a positive correlation between insulin and homeostatic model assessment indexes - insulin resistance, interleukin-18 expression in adipose tissue and an inverse correlation between some glucometabolic variables and leukocyte expression of NLR pyrin domain containing 3 and Caspase-1 were observed. No significant effects of long-term exercise training were observed on the inflammasome-related mediators in our patients with combined coronary artery disease and type 2 diabetes mellitus. The observed correlations may indicate a pro-inflammatory state in adipose tissue by overweight and a compensatory downregulation of these mediators in circulating leucocytes.

Bicuspid aortic valve behaviour in elite athletes.

To determine the prevalence and characteristics of bicuspid aortic valve (BAV) among elite athletes and to analyse the effect of long-term exercise training on their aortas. Consecutive BAV and tricuspid aortic valve (TAV) elite athletes from a population of 5136 athletes evaluated at the Sports Medicine Center of the Spanish National Sports Council were identified using echocardiography. A total of 41 BAV elite athletes were matched with 41 TAV elite athletes, and 41 BAV non-athletic patients from three Spanish tertiary hospitals. Sixteen BAV elite athletes who had undergone at least two cardiac evaluations separated by more than 3 years were selected to assess their clinical course. The prevalence of BAV in elite athletes was 0.8%. The proximal ascending aorta was larger for both BAV groups in comparison to TAV athletes (P = 0.001). No differences in aortic diameters were found between BAV athletes and BAV non-athletes. In BAV elite athletes, the annual growth rates for aortic annulus, sinuses of Valsalva, sinotubular junction, and proximal ascending aorta were 0.04 ± 0.24, 0.11 ± 0.59, 0.14 ± 0.38, and 0.21 ± 0.44 mm/year, respectively. Aortic regurgitation was the only functional abnormality, but no significant progression was found. High-intensity training and sports competition may not aggravate BAV condition during elite athletes' careers. BAV elite athletes with mild-to-moderately dilated aortas may engage in high dynamic cardiovascular exercise without adverse consequences, although an echocardiographic follow-up is recommended.

Effect of Long-Term Exercise Training on lncRNAs Expression in the Vascular Injury of Insulin Resistance.

LncRNA microarray analysis was applied to investigate the exercise effect on the global differential expressions of lncRNA and mRNA in aorta endothelium in insulin resistance. Twenty-four male C57BL/6J mice were randomly divided into three groups: control group (n = 8), high-fat diet group (n = 8), and high-fat diet plus exercise training group (n = 8). An lncRNA microarray analysis was applied to investigate the global differential expressions of lncRNA and mRNA in aorta endothelium among three groups and the results were further verified by qPCR. Hypergeometric distribution analysis was applied to reveal the possible signaling. Exercise might alleviate the vascular injury of IR via FR030200-Col3A1, FR402720-Rnd1, and FR030200/FR402720-Rnd3 signalings in cytoskeletal rearrangement pathway; E2F1-FR030200/FR402720-Nnat and FR030200/ FR402720-Fam46a signalings in anti-inflammation pathway. This study identified a panel of dysregulated lncRNAs and mRNAs that might serve as potential biomarkers relevant to the vascular injury in insulin resistance induced by high-fat diet.

Effects of long-term exercise training on inflammasome-related mediators in patients with T2DM and CAD

Effects of long-term exercise training on inflammasome-related mediators in patients with T2DM and CAD

Quantifiable effects of regular exercise on zinc status in a healthy population-A systematic review.

Zinc is an essential mineral of which its functions have potential implications on exercise performance and beneficial adaptations of physical activity. While the effects of aerobic exercise on zinc metabolism acutely have been well described, the effect of long-term exercise training on zinc status remains unclear. The present review aims to determine the effects of exercise training on markers of zinc status in an apparently healthy adult population. We conducted a systematic literature search on PubMed, Scopus, SPORTDiscus and Cochrane Library from inception to 28 January 2016 to identify interventional or cohort studies that investigated the effects of exercise training on indices of zinc status. Pairwise comparisons of mean differences in within-group change were calculated and summarised visually in forest plots. Six studies satisfied the inclusion criteria for the systematic review, of which 5 studies included data on changes in serum zinc concentrations and 3 studies provided changes in dietary zinc intake. Two comparisons showed significantly higher increase of serum zinc concentrations in the exercise group compared to control, while one comparison reported significantly lower change in serum zinc for the exercising group. The exercise groups consumed significantly higher dietary zinc compared to controls in two comparisons. The present review revealed an incomplete evidence base in evaluating the effect of long-term exercise training on markers of zinc status. Further well-designed investigations are required to elucidate the relationship for establishment of dietary recommendation in populations who are continuing exercise interventions.

Procoagulant activity in patients with combined type 2 diabetes and coronary artery disease: No effects of long-term exercise training.

We investigated the effects of 12-month exercise training on hypercoagulability in patients with combined type 2 diabetes mellitus and coronary artery disease. Associations with severity of disease were further explored. Patients ( n = 131) were randomized to exercise training or a control group. Blood was collected at inclusion and after 12 months. Tissue factor, free and total tissue factor pathway inhibitor, prothrombin fragment 1 + 2 (F1 + 2) and D-dimer were determined by enzyme-linked immunosorbent assay and ex vivo thrombin generation by the calibrated automated thrombogram assay. Tissue factor and ex vivo thrombin generation increased from baseline to 12 months ( p < 0.01, all), with no significant differences in changes between groups. At baseline, free and total tissue factor pathway inhibitor significantly correlated to fasting glucose ( p < 0.01, both) and HbA1c ( p < 0.05, both). In patients with albuminuria ( n = 34), these correlations were strengthened, and elevated levels of D-dimer, free and total tissue factor pathway inhibitor ( p < 0.01, all) and decreased ex vivo thrombin generation ( p < 0.05, all) were observed. These results show no effects of exercise training on markers of hypercoagulability in our population with combined type 2 diabetes mellitus and coronary artery disease. The association between poor glycaemic control and tissue factor pathway inhibitor might indicate increased endothelial activation. More pronounced hypercoagulability and increased tissue factor pathway inhibitor were demonstrated in patients with albuminuria.

Long-term exercise training as a modulator of mammary cancer vascularization.

Breast cancer remains a leading cause of death by cancer worldwide. It is commonly accepted that angiogenesis and the expression of angiogenic factors such as vascular endothelial growth factor-A (VEGF-A) is associated with the increased risk of metastasis and poor patient outcome. This work aimed to evaluate the effects of long-term exercise training on the growth and vascularization of mammary tumors in a rat model. Fifty female Sprague-Dawley rats were divided into four groups: two N-methyl-N-nitrosourea (MNU)-exposed groups (exercised and sedentary) and two control groups (exercised and sedentary). MNU was administered once, intraperitoneally at 7 weeks-old. Animals were then exercised on a treadmill for 35 weeks. Mammary tumors were evaluated using thermography, ultrasonography [Power Doppler (PDI), B Flow and contrast-enhanced ultrasound (CEUS)], and immunohistochemistry (VEGF-A). Both, MNU sedentary and exercised groups showed 100% of tumor incidence, but exercised animals showed less tumors with an increased latency period. Exercise training also enhanced VEGF-A immunoexpression and vascularization (microvessel density, MVD) (p<0.05), and reduced histological aggressiveness. Ultrasound and thermal imaging analysis confirmed the enhanced vascularization of tumors on exercised animals. Long-term exercise training increased VEGF-A expression, leading to enhanced tumor vascularization and reduced tumor burden, multiplicity and histological aggressiveness.

Effects of lifelong exercise training on mammary tumorigenesis induced by MNU in female Sprague-Dawley rats.

Breast cancer is the most common malignancy in women worldwide. Several studies have suggested that exercise training may decrease the risk of breast cancer development. This study aimed to evaluate the effects of long-term exercise training on mammary tumorigenesis in an animal model of mammary cancer. Fifty female Sprague-Dawley rats were randomly divided into four groups: MNU sedentary, MNU exercised, control sedentary and control exercised. Animals from MNU groups received an intraperitoneal administration of N-methyl-N-nitrosourea (MNU). Animals were exercised on a treadmill during 35weeks. When animals were killed, blood samples were collected to determine the hematocrit and to perform the biochemical analysis. Mammary tumors were collected and histologically evaluated; the expression of ERs α and β was evaluated in tumor sections by immunohistochemistry. All survived animals from both MNU groups developed mammary tumors. The number of mammary tumors (p>0.05) and lesions (p=0.056) was lower in MNU exercised than in MNU sedentary animals. MNU exercised animals showed lower number of malignant lesions than MNU sedentary animals (p=0.020). C-reactive protein serum concentration was lower in exercised animals; however, the levels of 17-β estradiol were higher in exercised animals. Tumors from exercised animals exhibited higher expression of ER α than tumors from sedentary animals (p<0.05). This study analyzes the impact of the longest exercise training protocol on mammary tumorigenesis ever performed. We concluded that the lifelong endurance training has beneficial effects on mammary tumorigenesis in female rats (reduced the inflammation, the number of mammary tumors and lesions, and histological grade of malignancy). Additionally, the mammary tumors from MNU exercised group exhibited higher immunoexpression of ER α that is an indicator of well-differentiated tumors and better response to hormone therapy.