The effects of exercise training on muscle atrophy in haemodialysis patients

BACKGROUND

Patients with end-stage renal disease on haemodialysis (HD) have limited work capacity. Many structural and functional alterations in skeletal muscles contribute to this disability.

METHODS

To evaluate the effects of exercise training on uraemic myopathy, seven HD patients (mean age 44.1+/-17.2 years) were studied. Open muscle biopsies were taken from their vastus lateralis muscle before and after a 6-month exercise rehabilitation programme and examined by routine light- and transmission electron-microscopy. Histochemical stainings of frozen sections were performed and morphometric analysis was also applied to estimate the proportion of each fibre type and the muscle fibre area. Spiroergometric and neurophysiological testing and peak extension forces of the lower limbs were measured before and after exercise training.

RESULTS

All patients showed impaired exercise capacity, which was associated with marked muscular atrophy (mean area 2548+/-463 microm2) and reduction in muscle strength and nerve conduction velocity. All types of fibres were atrophied, but type II were more affected. The ultrastructural study showed severe degenerative changes in skeletal muscle fibres, mitochondria, and capillaries. Exercise training had an impressive effect on muscular atrophy; in particular the proportion of type II fibres increased by 51% and mean muscle fibre area by 29%. Favourable changes were also seen on the structure and number of capillaries and mitochondria. These results were confirmed by a 48% increase in VO2 peak and a 29% in exercise time, as well as an improvement in the peak muscle strength of the lower limbs and in nerve conduction velocity.

CONCLUSIONS

Skeletal muscle atrophy in HD patients contribute to their poor exercise tolerance. The application of an exercise training rehabilitation programme improved muscle atrophy markedly, and therefore had beneficial effects in overall work performance.

Exercise training in patients with end-stage renal disease on hemodialysis: comparison of three rehabilitation programs

Functional capacity of end-stage renal disease patients is dramatically impaired. Although exercise training programs appear to have beneficial morphological, functional and psychosocial effects in end-stage renal disease patients on hemodialysis (HD), the adherence rate is high. The purpose of this study was to compare the effects of three modes of exercise training on aerobic capacity and to identify the most favourable, efficient and preferable to patients on HD with regard to functional improvements and participation rate in the programs. Fifty-eight volunteer patients were screened for low-risk status and selected from the dialysis population. The 48 patients who completed the study protocol were randomly assigned either to one of the three training groups or to a control group. Sixteen of them (Group A - mean age 46.4+/-13.9 years) completed a 6-month supervised outpatient exercise renal rehabilitation program consisting of three weekly sessions of aerobic and strengthening training on the non-dialysis days; 10 (Group B - mean age 48.3+/-12.1 years) completed a 6-month exercise program during HD; 10 (Group C - mean age 51.4+/-12.5 years) followed an unsupervised moderate exercise program at home, and 12 patients (Group D-mean age 50.2+/-7.9 years) were used as patient controls. The level of anemia, the medications and the HD prescription remained stable during the study. Fifteen sex- and age-matched sedentary individuals (Group E - mean age 46.9+/-6.4 years) comprised a healthy control group for baseline data. All subjects at the beginning and end of the study underwent clinical examination, laboratory tests and a treadmill exercise test to fatigue endpoints with direct measurement of aerobic capacity. Group A had a higher dropout rate (24%) compared to groups B (17%) and C (17%). Peak oxygen consumption (VO2 peak) increased by 43% (p < 0.05), anaerobic threshold (VO2AT) by 37% (p < 0.05) and exercise time by 33% (p < 0.05) after training in Group A; by 24% (p < 0.05), 18% (p < 0.05) and 22% (p < 0.05), respectively, in B; and by 17% (p < 0.05), 8% (p < 0.05) and 14% (p < 0.05), respectively, in C; while both remained almost unchanged in Group D. These results demonstrate that intense exercise training on non-dialysis days is the most effective way of training, whereas exercise during HD is also effective and preferable.

Effects of intradialytic exercise training on health-related quality of life indices in haemodialysis patients

OBJECTIVE

To assess the effects of intradialytic exercise training on health-related quality of life indices in haemodialysis patients.

SUBJECTS/PATIENTS

Thirty-five patients on haemodialysis, with a mean (SD) age of 48.8 (13.9) years, volunteered to participate in the study. They were randomized either to rehabilitation group (group A: 19 patients), following a 10-month intradialytic exercise training programme or to control group (group B: 14 patients). After the randomization, two of the patients, one of each group, withdrew from the study for reasons unrelated to exercise training.

METHOD

All patients at the beginning and the end of the study underwent clinical examination, laboratory tests and a treadmill exercise testing with spiroergometric study for the evaluation of their aerobic capacity (Vo(2peak)). A formal psychosocial assessment, which included affective (Beck Depression Inventory), health-related quality of life (Quality of Life Index, Living Questionnaire of Minnesota, Life Satisfaction Index and Short Form-36 questionnaire) and personality (Eysenck Personality Questionnaire) parameters, was evaluated at beginning and end of the study. The dose of erythropoietin was changed as needed, according to the level of the haemoglobin, aiming to keep it at 11 (2) g/dL during the study.

RESULTS

Baseline values were similar between the two groups. After training in group A, Vo(2peak) was increased by 21.1% (P<0.05) and exercise time by 23.6% (P<0.05). Moreover, group A showed a decrease in self-reported depression (Beck Depression Index) of 39.4% (P<0.001). In addition, trained patients demonstrated a significant improvement in Quality of Life Index (from 6.5 (1.8) to 9.0 (1.3), P<0.001) and Life Satisfaction Index (from 44.8 (8.6) to 53.0 (5.6), P<0.001), and an increase in the Physical Component Scale of the SF-36 (from 40.5 (5.6) to 44.5 (5.5), P<0.05), while the Mental Component Scale remained unchanged. Multiple regression analysis indicated that the improvement in quality of life depended on the participation in exercise programmes, the effects of training and the reduction in the level of depression. No changes were observed in Eysenck Personality Questionnaire by the end of the study, while all the above parameters remained almost unchanged in the controls.

CONCLUSION

The results demonstrated that intradialytic exercise training improves both physical functioning and psychological status in haemodialysis patients, leading to an improvement of patients' quality of life.

Cardiac Rehabilitation Availability and Density around the Globe

BACKGROUND

Despite the epidemic of cardiovascular disease and the benefits of cardiac rehabilitation (CR), availability is known to be insufficient, although this is not quantified. This study ascertained CR availability, volumes and its drivers, and density.

METHODS

A survey was administered to CR programs globally. Cardiac associations and local champions facilitated program identification. Factors associated with volumes were assessed using generalized linear mixed models, and compared by World Health Organization region. Density (i.e. annual ischemic heart disease [IHD] incidence estimate from Global Burden of Disease study divided by national CR capacity) was computed.

FINDINGS

CR was available in 111/203 (54.7%) countries; data were collected in 93 (83.8% country response; N = 1082 surveys, 32.1% program response rate). Availability by region ranged from 80.7% of countries in Europe, to 17.0% in Africa (p < .001). There were 5753 programs globally that could serve 1,655,083 patients/year, despite an estimated 20,279,651 incident IHD cases globally/year. Volume was significantly greater where patients were systematically referred (odds ratio [OR] = 1.36, 95% confidence interval [CI] = 1.35-1.38) and programs offered alternative models (OR = 1.05, 95%CI = 1.04-1.06), and significantly lower with private (OR = .92, 95%CI = .91-.93) or public (OR = .83, 95%CI = .82-84) funding compared to hybrid sources.Median capacity (i.e., number of patients a program could serve annually) was 246/program (Q25-Q75 = 150-390). The absolute density was one CR spot per 11 IHD cases in countries with CR, and 12 globally.

INTERPRETATION

CR is available in only half of countries globally. Where offered, capacity is grossly insufficient, such that most patients will not derive the benefits associated with participation.

Nature of Cardiac Rehabilitation Around the Globe

BACKGROUND

Cardiac rehabilitation (CR) is a clinically-effective but complex model of care. The purpose of this study was to characterize the nature of CR programs around the world, in relation to guideline recommendations, and compare this by World Health Organization (WHO) region.

METHODS

In this cross-sectional study, a piloted survey was administered online to CR programs globally. Cardiac associations and local champions facilitated program identification. Quality (benchmark of ≥ 75% of programs in a given country meeting each of 20 indicators) was ranked. Results were compared by WHO region using generalized linear mixed models.

FINDINGS

111/203 (54.7%) countries in the world offer CR; data were collected in 93 (83.8%; N = 1082 surveys, 32.1% program response rate). The most commonly-accepted indications were: myocardial infarction (n = 832, 97.4%), percutaneous coronary intervention (n = 820, 96.1%; 0.10), and coronary artery bypass surgery (n = 817, 95.8%). Most programs were led by physicians (n = 680; 69.1%). The most common CR providers (mean = 5.9 ± 2.8/program) were: nurses (n = 816, 88.1%; low in Africa, p < 0.001), dietitians (n = 739, 80.2%), and physiotherapists (n = 733, 79.3%). The most commonly-offered core components (mean = 8.7 ± 1.9 program) were: initial assessment (n = 939, 98.8%; most commonly for hypertension, tobacco, and physical inactivity), risk factor management (n = 928, 98.2%), patient education (n = 895, 96.9%), and exercise (n = 898, 94.3%; lower in Western Pacific, p < 0.01). All regions met ≥ 16/20 quality indicators, but quality was < 75% for tobacco cessation and return-to-work counseling (lower in Americas, p = < 0.05).

INTERPRETATION

This first-ever survey of CR around the globe suggests CR quality is high. However, there is significant regional variation, which could impact patient outcomes.

Exercise renal rehabilitation program: psychosocial effects

The aim of this study was to assess the psychosocial effects of exercise training on hemodialysis (HD) patients. Thirty-one uremic patients, aged 50.6+/-11.6 years, on maintenance HD were studied. Twenty patients were selected at random for a 6-month exercise renal rehabilitation program (ERRP) consisting of 3 weekly sessions of exercise training. The other 11 patients were assigned to sedentary control status. A formal psychosocial assessment, which included affective (Beck Depression Inventory, BDI), quality of life (Quality of Life Index, QLI) and personality (Eysenck Personality Questionnaire, EPQ) parameters, was performed with validated questionnaires at the beginning and the end of the ERRP. After training significant improvement occurred in physical capacity (VO2max increased from 16.8+/-6.2 to 23.2+/-7.6 ml/kg/min, p < 0.05). Although the level of depression did not differ betwen the 2 groups at pretesting, the ERRP group showed a decrease in their self-report of depression (decrease in BDI score value, from 21.0+/-10.4 to 13.7+/-9.5, p < 0.05) after the training program. From the relationship between the baseline levels of BDI depression and changes in VO2max in the ERRP group it was suggested that the most severely depressed patients got the greatest beneficial effects from exercise training. Moreover, trained patients demonstrated an improvement in QLI (from 6.3+/-1.5 to 9.0+/-0.9, p < 0.05). This improvement was found to be dependent on the participation in ERRP, the effects of the training and the improvement in the depression. All the above functional and psychosocial parameters remained unchanged in the controls. The results demonstrate that ERRP is an effective emotional therapeutic method for HD patients and improves their quality of life.

Cardiac effects of exercise rehabilitation in hemodialysis patients

Exercise training has well documented beneficial effects in a variety of cardiac disorders. End stage renal disease patients present many cardiovascular complications and suffer from impaired exercise capacity. No study to date has adequately examined the cardiac responses to exercise training in renal patients on hemodialysis (HD). To determine the effects of an exercise rehabilitation program on the left ventricular function at rest and during submaximal effort, 38 end-stage renal disease patients on maintenance HD were randomised into three groups. Sixteen of them (group A--mean age 46.4+/-13.9 years), without clinical features of heart failure, participated in a 6-month supervised exercise renal rehabilitation program consisting of three weekly sessions of aerobic training, 10 (group B--mean age 51.4+/-12.5 years) followed a moderate exercise program at home, and the other 12 (group C--mean age 50.2+/-7.9 years) were not trained and remained as controls. The level of anemia and the HD prescription remained constant during the study. Fifteen sex- and age-matched sedentary individuals (group D--mean age 46.9+/-6.4 years) were the healthy controls. All subjects at the start and end of the program underwent physical examination, laboratory tests, treadmill exercise testing, M-mode and 2-D echocardiograms performed at rest and at peak of supine bicycle exercise. Left ventricular volumes (EDV, ESV) and mass (LVM) were measured and ejection fraction (EF), stroke volume index (SVI) and cardiac output index (COI) were calculated by standard formulae. The maximal oxygen consumption increased by 43% (P<0.001) and the exercise time by 33% (P<0.001) after training in group A, by 17% (P<0.001) and 14% (P<0.01), respectively, in B, and both remained unchanged in group C. Training in group A was also associated with an increase in LVIDd (from 52.1+/-6.4 to 54.0+/-6.1 mm, P<0.001) and LVM (226+/-67 to 240+/-84 g, P<0.05) at rest with no change noted in groups B and C. Following a 6-month exercise training in group A an increase was also found in the resting EF by 5% (P<0.01) and SVI by 14% (P<0.001). There was no change found in groups B and C. Supine bicycle exercise after training in group A was associated with an improvement in EF by 14% compared to the pre-training change (P<0.001), SVI by 14% (P<0.001) and COI by 73% (P<0.001). These changes from rest to submaximal exercise were less pronounced in group B following training at home. The untrained patients demonstrated no changes in LV systolic function over the 6-month period. These results demonstrate that intense exercise training improves LV systolic function at rest in HD patients; both intense and moderate physical training leads to enhanced cardiac performance during supine submaximal exercise.

Effects of physical training on heart rate variability in patients on hemodialysis

Dysfunction of the cardiac autonomic nervous system is a known complication of end-stage renal disease. The objective of the study was to mainly investigate the effects of physical training on 24-hour vagal cardiac activity in dialysis patients. Sixty chronic uremic patients (mean age 48 +/- 12 years) on maintenance hemodialysis were studied. After initial evaluation, 30 patients (group A) were randomly assigned to a 6-month exercise training program (3/week). The other 30 patients (group B) and 30 nonuremic sedentary persons (group C) remained untrained and were used as controls. Parasympathetic activity was assessed at the beginning and the end of the study noninvasively from 24-hour electrocardiographic ambulatory monitoring by calculating heart rate variability (HRV). HRV index, mean NN interval, and standard deviation NN (SDNN) were measured according to the "triangular method." At baseline HRV index, mean RR, SDNN, and aerobic capacity were significantly reduced in both hemodialysis groups compared with values in group C. Also, 40% of all patients on hemodialysis and 16% of group C had arrhythmias (Lown class >II). Moreover, hemodialysis patients with a more depressed HRV index (<25, n = 37) had a higher incidence of arrhythmias (60%) compared to those with HRV index >25 (p <0.05). Exercise training in group A significantly increased HRV index from 22 +/- 7 to 28 +/- 9 (p <0.05) and SDNN from 0.11 +/- 0.03 to 0.13 +/- 0.04 (p <0.05). Furthermore, fewer patients continued to have an HRV index <25 (by 40%) and arrhythmias (by 33%) compared with baseline data. Training was also associated with a significant improvement in fitness level, as assessed by maximal oxygen consumption (by 41%; p <0.05) and exercise testing duration (by 33%; p <0.05). There was a significant correlation in HRV index and maximal oxygen consumption. No changes were observed in the control groups between baseline and follow-up data. Results demonstrate that physical training in hemodialysis patients augments cardiac vagal activity and decreases vulnerability to arrhythmias.

Importance of characteristics and modalities of physical activity and exercise in defining the benefits to cardiovascular health within the general population: recommendations from the EACPR (Part I)

Over the last decades, more and more evidence is accumulated that physical activity (PA) and exercise interventions are essential components in primary and secondary prevention for cardiovascular disease. However, it is less clear whether and which type of PA and exercise intervention (aerobic exercise, dynamic resistive exercise, or both) or characteristic of exercise (frequency, intensity, time or duration, and volume) would yield more benefit in achieving cardiovascular health. The present paper, as the first of a series of three, will make specific recommendations on the importance of these characteristics for cardiovascular health in the population at large. The guidance offered in this series of papers is aimed at medical doctors, health practitioners, kinesiologists, physiotherapists and exercise physiologists, politicians, public health policy makers, and the individual member of the public. Based on previous and the current literature, recommendations from the European Association on Cardiovascular Prevention and Rehabilitation are formulated regarding type, volume, and intensity of PA and exercise.

Effect of Moderate Aerobic Exercise Training on Endothelial Function and Arterial Stiffness in CKD Stages 3-4: A Randomized Controlled Trial

BACKGROUND

Evidence of a beneficial effect of exercise training on mediators of vascular disease is accumulating in chronic kidney disease (CKD), but its effect on vascular function in vivo still has to be established. The present study was designed to investigate whether a formal aerobic exercise training program improves peripheral endothelial function in patients with CKD stages 3 to 4.

STUDY DESIGN

Randomized controlled trial with a parallel-group design.

SETTING & PARTICIPANTS

48 patients with CKD stages 3 to 4 without established cardiovascular disease were randomly assigned to either an exercise training program or usual care. 40 patients completed the study (exercise training, 19; usual care, 21).

INTERVENTION

The 3-month home-based aerobic training program consisted of 4 daily cycling sessions of 10 minutes each at a target heart rate, calculated as 90% of the heart rate achieved at the anaerobic threshold. Patients in the usual-care group were given standard therapy.

OUTCOMES

The primary outcome was peripheral endothelial function. Secondary outcomes were aerobic capacity, arterial stiffness, numbers of endothelial (EPCs) and osteogenic progenitor cells (OPCs), migratory function of circulatory angiogenic cells, and health-related quality of life.

MEASUREMENTS

Endothelial function was assessed with flow-mediated dilation of the brachial artery, aerobic capacity by peak oxygen uptake (VO(2peak)), arterial stiffness by carotid-femoral pulse wave velocity, numbers of EPCs and OPCs by flow cytometry, circulatory angiogenic cell function by an in vitro migratory assay, and quality of life by the Kidney Disease Quality of Life-Short Form questionnaire.

RESULTS

Exercise training significantly improved VO(2peak) and quality of life, but not in vivo vascular function (flow-mediated dilation and carotid-femoral pulse wave velocity) or cellular markers for vascular function (EPC and OPC count and circulatory angiogenic cell migratory function).

LIMITATIONS

Short duration and intermittent nature of the exercise intervention.

CONCLUSIONS

In patients with CKD stages 3 to 4 without overt cardiovascular disease, 3 months of aerobic exercise training improved VO(2peak) and quality of life, without altering endothelial function or arterial stiffness.

Quality of life, psychological and physiological changes following exercise training in patients with chronic heart failure

OBJECTIVE

To assess the physiological and psychosocial effects of exercise training in chronic heart failure.

SUBJECTS/PATIENTS

Twenty-six men with heart failure (New York Heart Association functional classes II and III) aged 52.5 (SD 9.8) years, were studied.

METHODS

The subjects were randomized either to rehabilitation group (Group A: 16 patients), participating in a 6-month exercise training program, or to control group (Group B: 10 patients). A psychosocial assessment, which included affective (Beck Depression Inventory and Hospital Anxiety and Depression Scale), quality of life (Quality of Life Index, Minnesota Living with Heart Failure Questionnaire and the Scale of Life Satisfaction) and personality (Eysenck Personality Questionnaire) parameters, was performed at the beginning and the end of the study.

RESULTS

After training VO2 peak increased by 36% and exercise time by 35%, p < 0.05. A significant decrease in anxiety and depression was also observed. Moreover, trained patients demonstrated a significant improvement in quality of life. No significant correlations were found between deltaVO2 peak and all psychosocial parameter gains. However, the more depressed patients showed the largest physiological responses.

CONCLUSION

An exercise rehabilitation program in patients with chronic heart failure is useful for improving their work capacity and psychosocial status. Improvements in psychological status seem to be independent of the aerobic gains.

ESC Study Group of Sports Cardiology Position Paper on adverse cardiovascular effects of doping in athletes

The use of doping substances and methods is extensive not only among elite athletes, but also among amateur and recreational athletes. Many types of drugs are used by athletes to enhance performance, to reduce anxiety, to increase muscle mass, to reduce weight or to mask the use of other drugs during testing. However, the abuse of doping substances and methods has been associated with the occurrence of numerous health side-effects. The adverse effects depend on the type of the consumed drug, as well as the amount and duration of intake and the sensitivity of the body, since there is a large inter-individual variability in responses to a drug. Usually the doses used in sports are much higher than those used for therapeutic purposes and the use of several drugs in combination is frequent, leading to higher risk of side-effects. Among biomedical side-effects of doping, the cardiovascular ones are the most deleterious. Myocardial infarction, hyperlipidemia, hypertension, thrombosis, arrythmogenesis, heart failure and sudden cardiac death have been noted following drug abuse. This paper reviews the literature on the adverse cardiovascular effects after abuse of prohibited substances and methods in athletes, aiming to inform physicians, trainers and athletes and to discourage individuals from using drugs during sports.

Heart rate variability modifications following exercise training in type 2 diabetic patients with definite cardiac autonomic neuropathy

OBJECTIVES

Cardiac autonomic neuropathy (CAN) as a result of diabetic autonomic neuropathy is positively related to a poor prognosis in diabetic patients. The measurement of heart rate variability (HRV) is a remarkable index of cardiac autonomic dysfunction. The aim of this study was to examine the effects of long-term exercise training on HRV in type 2 diabetic patients with definite CAN.

METHODS

Seventeen type 2 diabetic patients with definite CAN (group A: 56.2 years (SD 5.8)) and 15 without CAN (group B: 55.8 years (SD 5.6)) participated in the study. All patients followed an aerobic exercise training programme three times a week for 6 months; the intensity of the session was 70% to 85% of heart rate reserve. At the beginning and end of the study all subjects underwent graded maximal exercise testing with spiroergometry for the evaluation of their aerobic capacity (VO(2)peak). Moreover, time and frequency domain indices of HRV were obtained from 24 h ambulatory continuous ECG Holter recordings.

RESULTS

At baseline, all measurements of HRV indices were significantly reduced in group A compared with group B (p<0.05). Moreover, group A reached a significantly lower VO(2)peak by 14.8% compared with group B (p<0.05). Following the exercise training programme, the SD of all normal-to-normal RR intervals in the entire recording (SDNN) was increased by 18.8% (p<0.05) and 13.8% (p<0.05), the square root of the average of sum of squares of difference between adjacent filtered RR intervals (rMSSd) was increased by 35% (p<0.05) and 15.2% (p<0.05), and the percentage of differences between adjacent filtered RR intervals which was greater than 50 ms for the entire analysis (pNN50) was increased by 400% (p<0.05) and 67.9% (p<0.05) in groups A and B, respectively. Regarding the frequency domain indices, only the high frequency power (HF) was found to be significantly increased in group A. At the end of the exercise training programme, SDNN, rMSSd and low frequency power (LF) were significantly lower (24.3% (p<0.05), 20.3% (p<0.05) and 40% (p<0.05), respectively) in group A compared with group B. Also, VO(2)peak increased by 17.8% (p<0.05) in group A and by 11% (p<0.05) in group B. Furthermore, the exercise training programme had significant effects on blood lipid and glucose levels and glycosylated haemoglobin (HbA(1c)) in both groups.

CONCLUSIONS

The results indicate that 6-month aerobic exercise training improves the cardiac autonomic nervous system function in type 2 diabetic patients. However, more favourable effects are found in type 2 diabetic patients with definite CAN.

Central and peripheral adaptations to physical training in patients with end-stage renal disease

Renal replacement treatment options are life-saving treatments for patients with end-stage renal disease (ESRD). However, prolonged survival in patients with ESRD is associated with various functional and morphological disorders from almost all systems. Anaemia, deconditioning, cardiac dysfunction. impairment of cardiac autonomic control and skeletal muscle weakness and fatigue, primarily because of 'uraemic' myopathy and neuropathy, are the main predisposing factors for their poor functional ability. Physical training is being recommended as a complementary therapeutic modality. There are generally 3 methods of exercise training applied in patients with ESRD: (i) the supervised outpatient programme that is held in a rehabilitation centre; (ii) a home exercise rehabilitation programme; and (iii) exercise rehabilitation programme during the first hours of the haemodialysis treatment in the renal unit. All the available training data show that the application of an exercise training programme in patients with ESRD enhances their physical fitness. This improvement is due to central and mainly peripheral adaptations. Exercise training in these patients increases aerobic capacity, causes favourable left ventricular functional adaptations, reduces blood pressure in patients with hypertension, modifies other coronary risk factors, increases the cardiac vagal activity and suppresses the incidence of cardiac arrhythmias. Moreover, exercise training has beneficial effects on muscle structural and functional abnormalities. These central and peripheral adaptations to exercise training cause an increase in their functional capacity and offer them achance of a better quality of life. Moreover, exercise training improves exercisee tolerance of renal post-transplant patients.

A randomized controlled trial of exercise training on cardiovascular and autonomic function among renal transplant recipients

BACKGROUND

There are conflicting data regarding the effects of renal transplantation (RT) on uraemic autonomic dysfunction. Moreover, no study has examined the impact of physical training on the cardiac autonomic function in RT patients. Thus, we studied the effects of exercise training on heart rate variability (HRV) and arterial baroreflex sensitivity (BRS), which are sensitive markers of cardiac autonomic outflow, in RT recipients.

METHODS

Eleven patients (Exercise group-aged 52.1 ± 5.6 years) were studied before and after 6 months of exercise training. Twelve age- and sex- matched RT patients (Sedentary) and 12 healthy sedentary individuals (Healthy), who remained untrained, served as controls. At baseline and follow-up, all the subjects underwent cardiopulmonary exercise testing for the evaluation of peak oxygen consumption (VO2peak), a tilt test for the evaluation of BRS and baroreflex effectiveness index (BEI) and an ambulatory 24-h Holter monitoring for time- and frequency-domain measures of HRV.

RESULTS

In the exercise group, VO2peak increased by 15.8% (P < 0.05) and all depressed HRV and BRS indices were significantly improved after training. Specifically, the standard deviation of all normal-to-normal (NN) intervals (SDNN) significantly increased by 92.5%, the root-mean-square of the differences between consecutive NN intervals by 45.4%, the percentage value of NN50 count by 58.2%, the high-frequency by 74.8% and low-frequency spectral power by 41.6%, BRS by 43.7% and BEI by 57.3%. None of the variables studied was altered over time in either control group.

CONCLUSIONS

The increased cardiorespiratory fitness by exercise training was associated with an improved BRS function and a modification of the sympathovagal control of HRV towards a persistent increase in parasympathetic tone. These alterations may lead to a better cardiovascular prognosis in RT recipients.

Current best evidence recommendations on measurement and interpretation of physical function in patients with chronic kidney disease

Chronic kidney disease (CKD) is becoming a serious health problem throughout the world and is one of the most potent known risk factors for cardiovascular disease. Deterioration of physical function is accelerated in patients with CKD to levels that significantly impact on clinically and patient-important outcomes such as morbidity, employment, quality of life and, ultimately, survival. However, meaningful interpretation of the existing physical function-related literature in adult patients with CKD is hindered, possibly due to inconsistent choice of methodology, assessment tools and reporting of data. The current comprehensive review of the literature aims to provide the theoretical rationale and framework for physical function assessment and to identify the prevailing approaches to (i) the characterization (classification and terminology), (ii) interpretation, and (iii) reporting of physical function assessment in people with CKD. Comprehensive assessment of physical function can provide important information about the presence of 'physiological impairment' at a body systems level (exercise tolerance under well controlled, laboratory-based procedures), 'functional limitations' (physical performance during tasks imitating usual daily, personal or occupational tasks) and 'functional disability' (via self-reported physical functioning in the context of a socio-cultural environment). The selection of physical function assessment tools should be guided by the primary purpose of the assessment (e.g. research or routine clinical monitoring), by the overall scientific 'soundness' of the chosen tool (e.g. validity, utility, reproducibility, responsiveness characteristics) and by operational factors (e.g. patient collaboration, cost, personnel expertise). Recommendations for tests, methods and protocols are therefore presented, for the assessment of cardiorespiratory and muscular fitness, physical performance and self-reported physical functioning. These recommendations are based on synthesis of available information as derived from controlled exercise training interventions in adult patients with CKD. Special considerations for physical function assessment and suggestions for future research are also addressed. Such an information synthesis might promote greater standardization of the physical function assessment of patients with CKD in routine clinical care or research settings. This would potentially lead to generation of adequate scientific decision-making criteria to help researchers and healthcare providers in selecting the most appropriate measures according to the physical function areas assessed, and to accurately and meaningfully characterize and compare patients' responses to therapeutic interventions.

Effects of exercise training with traditional dancing on functional capacity and quality of life in patients with schizophrenia: a randomized controlled study

OBJECTIVE

To examine the effects of an eight-month exercise training programme with Greek traditional dancing on functional capacity and quality of life in patients with schizophrenia.

DESIGN

Randomized controlled trial.

SETTING

Sports Medicine Laboratory.

SUBJECTS

A total of 31 patients, aged 59.9 ± 14.1 years.

INTERVENTIONS

They were randomly assigned either to a Greek traditional dancing programme (Group A) or to a sedentary control group (Group B).

MAIN MEASURES

A functional capacity assessment was performed at baseline and the end of the study. Global Assessment of Functioning Scale and Positive and Negative Syndrome Scale were also used. Quality of life was examined using the Quality of Life and Satisfaction questionnaire.

RESULTS

After the eight months, Group A increased walking distance in the 6-minute walk test (328.4 ± 35.9 vs. 238.0 ± 47.6 m), sit-to-stand test (19.1 ± 1.8 vs. 25.1 ± 1.4 seconds), Berg Balance Scale score (53.1 ± 2.1 vs. 43.2 ± 6.7), lower limbs maximal isometric force (77.7 ± 25.7 vs. 51.0 ± 29.8 lb), Positive and Negative Syndrome Scale total score (77.0 ± 23.1 vs. 82.0 ± 24.4), Global Assessment of Functioning Scale total score (51.3 ± 15.5 vs. 47.7 ± 13.3) and Quality of Life total score (34.9 ± 5.2 vs. 28 ± 4.5), compared with Group B.

CONCLUSIONS

Our results demonstrate that Greek traditional dances improve functional capacity and quality of life in patients with schizophrenia.

Vascular effects of exercise training in CKD: current evidence and pathophysiological mechanisms

Cardiovascular disease remains the main cause of morbidity and mortality in patients with CKD, an observation that cannot be explained by the coexistence of traditional risk factors alone. Recently, other mechanisms, such as alterations in nitric oxide bioavailability, impaired endothelial repair mechanisms, inflammation, and oxidative stress (all characteristic in CKD), have gained much attention as mediators for the increased cardiovascular risk. Regular physical training is a valuable nonpharmacological intervention for primary and secondary prevention of cardiovascular disease. Likewise, the benefits of exercise training on exercise capacity and quality of life are increasingly recognized in patients with CKD. Furthermore, exercise training could also influence potential reversible mechanisms involved in atherosclerosis and arteriosclerosis. After discussing briefly the general concepts of vascular disease in CKD, this review provides an overview of the current evidence for the effects of exercise training at both clinical and preclinical levels. It concludes with some practical considerations on exercise training in this specific patient group.

White coat hypertension detected during screening of male adolescent athletes

We investigated the utility of the selective use of ambulatory BP monitoring (ABPM) and echocardiography in detecting truly hypertensive adolescents from a cohort of young adolescent athletes undergoing BP screening. A total of 410 athletes (aged 16.4+/-2.6 years) were screened and, if initial BP measurement detected a persistently elevated BP (>140 mm Hg systolic or >90 mm Hg diastolic), ABPM and echocardiography were performed. Eighteen clinically hypertensive cases (4.4%) were detected and evaluated with a 24-h ABPM. Sixteen of them were defined as having "white coat hypertension" because they were detected to have normal daytime and nocturnal BP. An elevated level of BP confirmed on ABPM was recorded in only two (0.5%) athletes. Echocardiography failed to demonstrate significant abnormalities.

Cardiovascular effects of doping substances, commonly prescribed medications and ergogenic aids in relation to sports: a position statement of the sport cardiology and exercise nucleus of the European Association of Preventive Cardiology

The use of substances and medications with potential cardiovascular effects among those practicing sports and physical activity has progressively increased in recent years. This is also connected to the promotion of physical activity and exercise as core aspects of a healthy lifestyle, which has led also to an increase in sport participation across all ages. In this context, three main users' categories can be identified, (i) professional and amateur athletes using substances to enhance their performance, (ii) people with chronic conditions, which include physical activity and sport in their therapeutic plan, in association with prescribed medications, and (iii) athletes and young individuals using supplements or ergogenic aids to integrate their diet or obtaining a cognitive enhancement effect. All the substances used for these purposes have been reported to have side effects, among whom the cardiovascular consequences are the most dangerous and could lead to cardiac events. The cardiovascular effect depends on the type of substance, the amount, the duration of use, and the individual response to the substances, considering the great variability in responses. This Position Paper reviews the recent literature and represents an update to the previously published Position Paper published in 2006. The objective is to inform physicians, athletes, coaches, and those participating in sport for a health enhancement purpose, about the adverse cardiovascular effects of doping substances, commonly prescribed medications and ergogenic aids, when associated with sport and exercise.