Aerobic exercise attenuates dysautonomia, cardiac diastolic dysfunctions, and hemodynamic overload in female mice with atherosclerosis

Cardiovascular risk increases during the aging process in women with atherosclerosis and exercise training is a strategy for management of cardiac risks in at-risk populations. Therefore, the aims of this study were to evaluate: (1) the influence of the aging process on cardiac function, hemodynamics, cardiovascular autonomic modulation, and baroreflex sensitivity in females with atherosclerosis at the onset of reproductive senescence; and (2) the impact of exercise training on age-related dysfunctions in this model. Eighteen Apolipoprotein-E knockout female mice were divided equally into young (Y), middle-aged (MA), and trained middle-aged (MAT). Echocardiographic exams were performed to verify cardiac morphology and function. Cannulation for direct recording of blood pressure and heart rate, and analysis of cardiovascular autonomic modulation, baroreflex sensitivity were performed. The MA had lower cardiac diastolic function (E'/A' ratio), and higher aortic thickness, heart rate and mean arterial pressure, lower heart rate variability and baroreflex sensitivity compared with Y. There were no differences between Y and MAT in these parameters. Positive correlation coefficients were found between aortic wall thickness with hemodynamics data. The aging process causes a series of deleterious effects such as hemodynamic overload and dysautonomia in female with atherosclerosis. Exercise training was effective in mitigating aged-related dysfunctions.

Effects of Exercise Intensity on Cardiometabolic Parameters of Ovariectomized Obese Mice

The aim of this study was to compare the effects of continuous-moderate vs. high-intensity interval aerobic training on cardiovascular and metabolic parameters in ovariectomized high-fat-fed mice. C57BL/6 female ovariectomized were divided into four groups (n=8): low-fat-fed sedentary (SLF); high-fat-fed sedentary (SHF); high-fat-fed moderate-intensity continuous trained (MICT-HF); and high-fat-fed high-intensity interval aerobic trained (HIIT-HF). The high-fat diet lasted 10 weeks. Ovariectomy was performed in the fourth week. The exercise training was carried out in the last four weeks of protocol. Fasting glycemia, oral glucose tolerance, arterial pressure, baroreflex sensitivity, and cardiovascular autonomic modulation were evaluated. Moderate-intensity continuous training prevented the increase in arterial pressure and promoted a reduction in HR at rest, associated with an improvement in the sympathovagal balance in MICT-HF vs. SHF. The high-intensity interval training reduced blood glucose and glucose intolerance in HIIT-HF vs. SHF and MICT-HF. In addition, it improved sympathovagal balance in HIIT-HF vs. SHF. Moderate-intensity continuous training was more effective in promoting cardiovascular benefits, while high-intensity interval training was more effective in promoting metabolic benefits.

Effects of pilates on physical-functional performance, quality of life and mood in older adults: Systematic review and meta-analysis of randomized clinical trials

OBJECTIVE

To systematically review the effects of pilates on physical-functional aspects and quality of life of older adults.

METHODS

We included randomized clinical trials whose participants were older adults, whose intervention was pilates exercises and that used a control group for comparison. The primary outcomes were balance, muscle strength, quality of life. Secondary outcomes were mood, autonomy, and flexibility. The searches were performed in the electronic databases Pubmed, Web of Science, LILACS, Cochrane Library and EMBASE, using terms from MeSH: Aged, elderly, Pilates-Based Exercises, Pilates Training, Pilates, Mat Pilates, Equipment-based Pilates, and synonyms, in May 2020. The meta-analysis, when possible, was performed using the mean and standard deviation values of the groups after the intervention period using the random effects model.

RESULTS

The search rendered 1639 studies, of which 28 articles corresponding to 24 ECRs (897 individuals) were included, most of the studies involved a female population. A meta-analysis was performed only in the balance variable, through the Berg Scale (three RCTs), where there were no significant differences between the intervention and control groups (2.06-95% CI: 1.31, 5.44, I²: 91%), and it was evaluated by the TUG (six RCTs), which showed a reduction of 0.92 seconds in the protocol execution (95% CI: 1.67, -0.17, I²: 62%).

CONCLUSION

This review demonstrate that the practice of pilates by older adults may have positive effects on some of the outcomes evaluated, these results should be interpreted with caution (methodological heterogeneity and a part present high risk of bias).

Impaired baroreflex sensitivity and increased systolic blood pressure variability in chronic post-ischemic stroke

OBJECTIVES

Acute post-stroke patients present cardiovascular autonomic dysfunction, which manifests as lower heart rate variability and impaired baroreflex sensitivity. However, few studies performed to date have evaluated cardiovascular autonomic function in chronic post-stroke patients. The aim of this study was to evaluate cardiovascular autonomic modulation in chronic post-ischemic stroke patients.

METHODS

The seventeen enrolled subjects were divided into a stroke group (SG, n=10, 5±1 years after stroke) and a control group (CG, n=7). Non-invasive curves for blood pressure were continuously recorded (Finometer®) for 15 minutes while the subject was in a supine position. Heart rate variability and blood pressure variability were analyzed in the time and frequency domains.

RESULTS

No differences were observed in systolic and diastolic pressure and heart rate between post-stroke patients and healthy individuals. The SG group had lower indexes for heart rate variability in the time domain (standard deviation of normal to normal R-R intervals, SDNN; variance of normal to normal R-R intervals, VarNN; and root mean square differences of successive R-R intervals, RMSSD) and a lower high-frequency band for heart rate variability than was observed in the CG. Systolic blood pressure variability and the low-frequency band for systolic pressure were higher in post-stroke patients, while the alpha index was lower in the SG than in the CG.

CONCLUSION

After ischemic stroke, affected patients present chronically reduced heart rate variability, impaired cardiac vagal modulation, increased systolic blood pressure variability and higher sympathetic vascular modulation along with impaired baroreflex sensitivity, which can increase the risk of cardiovascular events, despite adequate blood pressure control.

Effects of testosterone on lean mass gain in elderly men: systematic review with meta-analysis of controlled and randomized studies

The objective of this study was to evaluate the effects of steroid anabolic androgenic hormones use on lean mass gain in elderly men through a systematic review with a meta-analysis of randomized controlled studies. We systematically searched PubMed database until 4th October 2013. We included randomized placebo-controlled trials (RCT) that studied testosterone replacement therapy in men over 60 years of age, with total testosterone levels ≤550 ng/dl, observing gains in weight, lean mass tissue and fat mass as outcome. We excluded duplicated studies, studies which mixed men and women, and studies using weak androgens such as dehydroepiandrosterone or androstenedione. The initial search yielded 2681 articles, of which 26 were selected for full text analysis. In the end, 11 studies were included. However, 3 studies were not included in the meta-analysis. Meta-analysis showed that mean weight increased (lean mass), ranging from 1.65 (95 % CI, 1.61-1.69) to 6.20 (95 % CI, 5.22-7.18) kg, although it was heterogeneous (I (2) = 98 %). Effect estimate was 3.59 [2.38-4.81]. Androgen therapy decreased fat mass; effect estimate was -1.78 [-2.57, -0.99] that analysis had also a high level of heterogeneity (I (2) = 81 %). The results suggest that testosterone replacement therapy is able to increase muscle mass in elderly men and that is affected by the time that the treatment is carried out and the method of administration of the drug.

Low intensity resistance training improves systolic function and cardiovascular autonomic control in diabetic rats

AIMS

We evaluated the effects of low intensity resistance training (RT) on left ventricular (LV) function, baroreflex sensitivity (BRS), and cardiovascular autonomic control of streptozotocin-induced diabetic rats.

METHODS

Male Wistar rats were divided into (n=8 each group): sedentary control (SC), trained control (TC), sedentary diabetic (SD), and trained diabetic (TD). Trained groups underwent low intensity RT (40%-50% 1 repetition maximum) for 10 weeks. Echocardiographic evaluation, arterial pressure (AP), heart rate (HR), BRS, and autonomic measurements were performed.

RESULTS

Diabetes induced an increase in glycemia and a reduction in body weight in diabetics when compared with control animals. Diabetic rats displayed cardiac dysfunction, reduced systolic AP and HR, impaired BRS and autonomic derangement when compared to control rats. RT improved ejection fraction (SD: 68%±1.3% vs. TD: 75%±3.0%) and velocity of circumferential fiber shortening (SD: 0.32±0.02 vs. TD: 0.40±0.01 circ/seg.10(-4)). Trained diabetic rats presented increased AP (+10.2%), HR (+10.4%), and BRS after RT protocol.

CONCLUSIONS

Low intensity RT induced an increase in systolic function in diabetic rats. This may be due to positive LV remodeling and BRS improvement, which may have played an important role in the attenuation of hemodynamic impairment and cardiac autonomic neuropathy in streptozotocin-diabetic rats.