Progressive Exercise for Anabolism in Kidney Disease (PEAK): A Randomized, Controlled Trial of Resistance Training during Hemodialysis

Obesity, Chronic Kidney Disease, and Kidney Transplantation: An Evolving Relationship

Obesity has a fundamental role in driving the global kidney disease burden. The perplexing relationship of obesity with chronic kidney disease remains debated. However, a thorough understanding of the interplay of obesity in conjunction with chronic kidney disease and appropriate management options is lacking, leading to further increases in morbidity and mortality. Moreover, underutilization of bariatric procedures and unrealistic expectations of weight reduction based on body mass index, leading to poor access to kidney transplantation, are fueling the fire. In this review, we summarize the available data related to the obesity and chronic kidney disease association and its novel management options.

Reasons for Nonparticipation in a Sustained Hemodialysis Intradialytic Exercise Program

OBJECTIVE(S)

Patients with end-stage kidney disease requiring hemodialysis suffer frailty and poor physical function. Exercise can improve physical function; however, barriers exist to intradialytic exercise programs. The objective of this study was to explore patients' reasons for not exercising in an extant intradialytic exercise program.

DESIGN AND METHODS

We conducted a retrospective analysis reporting the reasons for not exercising in an intradialytic exercise program in two hemodialysis centers over a 4-week period. We explored whether patient characteristics and the presence of an exercise professional were associated with missed exercise sessions.

RESULTS

Seventy-five patients participating in the intradialytic exercise program completed 57% of prescribed intradialytic exercise sessions. The three most frequently reported reasons from patients not exercising were refusal (24%), followed by fatigue (19%) and symptoms (14%). Patients were more than twice as likely to exercise if a kinesiologist was present (odds ratio [OR]: 2.26, confidence interval [CI]: 1.5, 3.4 P = .03). They were less likely to exercise if they were women (OR: 0.66, CI: 0.45, 0.95 P = .002), had been on dialysis greater than 60 months (OR: 0.55, CI: 0.37, 0.80 P < .002), or had more than two comorbid conditions (OR: 0.63, CI: 0.43, 0.90, P = .01).

CONCLUSION

Patient adherence to intradialytic exercise programs is strongly associated with the presence of exercise professionals.

Exercise training in dialysis patients: impact on cardiovascular and skeletal muscle health

Dialysis patients show a high rate of reduced functional capacity, morbidity and mortality. Cardiovascular disorders, muscle atrophy and malnutrition play an essential role among the aetiological factors. Sedentary lifestyle characterizes them and contributes to the aggravation of the disorders. On the contrary, exercise training is an important preventive and therapeutic tool both for cardiovascular problems and for the appearance of muscle atrophy in dialysis patients. Regular exercise causes both central (cardiac) and peripheral (muscular) adaptations, improving functional capacity. In particular, circulatory system clinical trials in haemodialysis (HD) patients documented that exercise has favourable effects on heart function, promotes balance on the cardiac autonomic nervous system and contributes to the management of arterial hypertension. In the muscular system, it prevents muscle atrophy or contributes significantly to its treatment. The main preventive mechanisms of the beneficial effect of exercise on the muscles constitute the inhibition of the apoptotic processes and protein degradation. Exercise training in HD patients leads to an increase of muscle fibers, mitochondria and capillaries, and the combination of regular exercise and dietary strategies is even more effective in preventing or treating muscle atrophy. Finally, an improvement in functional capacity and quality of life was found also in peritoneal dialysis patients following exercise training.

How to Overcome Anabolic Resistance in Dialysis-Treated Patients?

A current hypothesis is that dialysis-treated patients are "anabolic resistant" i. e., their muscle protein synthesis (MPS) response to anabolic stimuli is blunted, an effect which leads to muscle wasting and poor physical performance in aging and in several chronic diseases. The importance of maintaining muscle mass and MPS is often neglected in dialysis-treated patients; better than to describe mechanisms leading to energy-protein wasting, the aim of this narrative review is to suggest possible strategies to overcome anabolic resistance in this patient's category. Food intake, in particular dietary protein, and physical activity, are the two major anabolic stimuli. Unfortunately, dialysis patients are often aged and have a sedentary behavior, all conditions which per se may induce a state of "anabolic resistance." In addition, patients on dialysis are exposed to amino acid or protein deprivation during the dialysis sessions. Unfortunately, the optimal amount and formula of protein/amino acid composition in supplements to maximixe MPS is still unknown in dialysis patients. In young healthy subjects, 20 g whey protein maximally stimulate MPS. However, recent observations suggest that dialysis patients need greater amounts of proteins than healthy subjects to maximally stimulate MPS. Since unneccesary amounts of amino acids could stimulate ureagenesis, toxins and acid production, it is urgent to obtain information on the optimal dose of proteins or amino acids/ketoacids to maximize MPS in this patients' population. In the meantime, the issue of maintaining muscle mass and function in dialysis-treated CKD patients needs not to be overlooked by the kidney community.

Exercise intolerance in kidney diseases: physiological contributors and therapeutic strategies

Exertional fatigue, defined as the overwhelming and debilitating sense of sustained exhaustion that impacts the ability to perform activities of daily living, is highly prevalent in chronic kidney disease (CKD) and end-stage renal disease (ESRD). Subjective reports of exertional fatigue are paralleled by objective measurements of exercise intolerance throughout the spectrum of the disease. The prevalence of exercise intolerance is clinically noteworthy, as it leads to increased frailty, worsened quality of life, and an increased risk of mortality. The physiological underpinnings of exercise intolerance are multifaceted and still not fully understood. This review aims to provide a comprehensive outline of the potential physiological contributors, both central and peripheral, to kidney disease-related exercise intolerance and highlight current and prospective interventions to target this symptom. In this review, the CKD-related metabolic derangements, cardiac and pulmonary dysfunction, altered physiological responses to oxygen consumption, vascular derangements, and sarcopenia are discussed in the context of exercise intolerance. Lifestyle interventions to improve exertional fatigue, such as aerobic and resistance exercise training, are discussed, and the lack of dietary interventions to improve exercise tolerance is highlighted. Current and prospective pharmaceutical and nutraceutical strategies to improve exertional fatigue are also broached. An extensive understanding of the pathophysiological mechanisms of exercise intolerance will allow for the development of more targeted therapeutic approached to improve exertional fatigue and health-related quality of life in CKD and ESRD.

Grip Strength in Adults and Children with Cystinosis

Introduction

Chronic kidney disease (CKD) is associated with impaired muscle strength. Patients with cystinosis have an increased risk for impaired muscle strength because of early development of CKD and cystinosis-induced myopathy. This study assesses muscle strength in patients with cystinosis and investigates risk factors of decreased muscle strength.

Methods

Adult and pediatric patients were recruited from Cystinosis Research Network conferences and a large pediatric nephrology clinic between 2017 and 2019. Patients and caregivers completed questionnaires on demographic characteristics, disease course, daily physical activity, and neuromuscular symptoms. Grip strength was assessed using a dynameter and calculated z-scores for age and sex were assessed for associations with patient characteristics.

Results

We included 76 patients with a mean grip strength z-score of −2.1 (SD, 1.1), which was lower than seen in patients with CKD without cystinosis. Male sex and delayed cysteamine initiation were independently associated with impaired grip strength. Among adults, a low level of physical activity was associated with lower grip strength z score, but no association was found in children. A third of the patients reported neuromuscular symptoms, with swallowing issues associated with lower grip strength. There was no significant correlation between eGFR and grip strength z-score.

Conclusion

Patients with cystinosis have impaired muscle strength compared with healthy control subjects and patients with CKD. This impairment is greater in male patients and in patients with late initiation of cysteamine therapy and is associated with lower physical activity. Further studies investigating the effect of different types of physical activities, optimizing cysteamine therapy, and other interventions are needed.

Effects of long-term intradialytic oral nutrition and exercise on muscle protein homeostasis and markers of mitochondrial content in patients on hemodialysis

Patients with end-stage kidney disease on maintenance hemodialysis commonly develop protein-energy wasting, a syndrome characterized by nutritional and metabolic abnormalities. Nutritional supplementation and exercise are recommended to prevent protein-energy wasting. In a 6-mo prospective randomized, open-label, clinical trial, we reported that the combination of resistance exercise and nutritional supplementation does not have an additive effect on lean body mass measured by dual-energy X-ray absorptiometry. To provide more mechanistic data, we performed a secondary analysis where we hypothesized that the combination of nutritional supplementation and resistance exercise would have additive effects on muscle protein accretion by stable isotope protein kinetic experiments, muscle mass by MRI, and mitochondrial content markers in muscle. We found that 6 mo of nutritional supplementation during hemodialysis increased muscle protein net balance [baseline: 2.5 (-17.8, 13.0) µg·100 mL-1·min-1 vs. 6 mo: 43.7 (13.0, 98.5) µg·100 mL-1·min-1, median (interquartile range), P = 0.04] and mid-thigh fat area [baseline: 162.3 (104.7, 226.6) cm2 vs. 6 mo: 181.9 (126.3, 279.2) cm2, median (interquartile range), P = 0.04]. Three months of nutritional supplementation also increased markers of mitochondrial content in muscle. Although the study is underpowered to detected differences, the combination of nutritional supplementation and exercise failed to show further benefit in protein accretion or muscle cross-sectional area. We conclude that long-term nutritional supplementation increases the skeletal muscle anabolic effect, the fat cross-sectional area of the thigh, and markers of mitochondrial content in skeletal muscle.

Effects of intradialytic cycling exercise on daily physical activity, physical fitness, body composition, and clinical parameters in high-volume online hemodiafiltration patients: a pilot randomized-controlled trial

PURPOSE

The mortality of dialysis patients treated with high-volume online hemodiafiltration (OL-HDF) is better than hemodialysis, but is still higher than healthy population. Low daily physical activity increases cardiovascular mortality. Addition of intradialytic exercise (IDX) program might improve physical activity and health status in OL-HDF patients. This pilot open-labeled randomized-controlled trial was conducted to evaluate the effects of IDX on physical activity and other clinical parameters in OL-HDF patients.

METHODS

Twelve OL-HDF patients were randomized into control (n = 6) or IDX (n = 6) groups. The subjects in IDX group were trained to exercise using a cycle ergometer for 60 min during each OL-HDF session. Physical activity measured as daily step count using a wrist-worn triaxial accelerometer, physical fitness, or cardiorespiratory fitness assessed by VO₂max and other physical performance tests, lean body mass determined by the Dual-energy X-ray absorptiometry (DXA), quality of life (QOL), and various parameters were compared between baseline and 6 months.

RESULTS

The baseline physical activity status was comparable. Following 6-month IDX, the physical activity was significantly improved in IDX group [+ 1048.79 (+ 741.50, + 2792.54) vs. - 362.06 (- 1626.82, - 167.47) steps/day, p = 0.01], while physical fitness and QOL were unchanged. The lean body mass parameters were preserved in the IDX group while seemed to decrease in the control group. Serum albumin was significantly increased in the IDX group (p = 0.01). The hemoglobin changes were significantly better (p = 0.01) and the erythropoietin resistance index was significantly lower in the IDX group (p = 0.03). Phosphate reduction was significantly greater in the IDX group (p = 0.04).

CONCLUSIONS

IDX could improve physical activity and other metabolic parameters in OL-HDF patients and these might contribute to further improvement in clinical and survival outcomes.

TRIAL REGISTRATION

ClinicalTrials.gov Registration: NCT03353844.

Effect of intradialytic progressive resistance exercise on physical fitness and quality of life in maintenance haemodialysis patients

Purpose

To investigate the impact of intradialytic progressive resistance exercise (IPRE) on physical fitness and quality of life in maintenance haemodialysis (MHD) patients.

Methods

Subjects were allocated randomly to the exercise group received IPRE and the control group underwent a haemodialysis session alone. Outcomes measured were including physical fitness ascertained by 6‐min walk test, sit‐to‐stand 10 test and handgrip strength. Kidney Disease Quality of Life Instrument was used to assess the quality of life, and also recorded the adverse event at each exercise session.

Results

A total of 87 patients were analysed: 43 in the exercise group and 44 in the control group. After 12 weeks, there were significant improvements in physical fitness and past of the dimension of the scale in the exercise group.

Conclusions

IPRE can improve the physical fitness and quality of life in patients underwent MHD with no serious adverse events or safety issues.

A Critical Review of Exercise Training in Hemodialysis Patients: Personalized Activity Prescriptions Are Needed

Exercise training appears to have modest or inconsistent benefits in hemodialysis patients. This may be due to the low volume and intensity of exercise often prescribed. To address this, research is needed to evaluate the efficacy of individualized exercise prescriptions as a component of a comprehensive lifestyle intervention strategy that gives patients more autonomy to choose preferred types of physical activity.

The Effect of Exercise on Nutritional Status and Body Composition in Hemodialysis: A Systematic Review

Chronic kidney disease (CKD) is associated with aggravating factors which can affect both body composition and nutritional status. The purpose of the present systematic review was to investigate the potential effects of any physical activity on body composition or nutritional status among patients with stage 5 CKD undergoing hemodialysis (HD). A literature search on PubMed, Scopus, Web of Science, Google Scholar, and Cochrane was conducted and 14 randomized clinical trials were included. Skeletal muscle index and mid-arm muscular circumference increased after resistance exercise, and the results on body mass index, % body fat, and lean body mass varied. Serum albumin and C-reactive protein, in most cases, showed a slight increase and decrease, respectively. An improvement was also observed in body strength and overall performance status. The results suggest that physical activity can be beneficial for both the body composition and nutritional status of patients undergoing HD and can help in the prevention of sarcopenia. However, further research is needed mainly in the field of nutritional status.

Effects of resistance training on kidney morphology of aged ovariectomized rats

With the advancing age, there is an increase of the incidence of chronic renal diseases. However, it is suggested that exercise, as resistance training, is a key factor in positively modulate the kidney structure and function. Thus, this study aimed to analyze the effects of estrogen deprivation and a moderate resistance protocol on the right kidney structure of rats. A total of 32 animals were randomly divided in four groups (n = 8/per group): control group (CG); resistance trained animals (RT); control ovariectomized animals (OvxC); and trained ovariectomized animals (OvxT). Sections of the right kidney were stained with hematoxylin and eosin for morphometry and blood was collected for biochemical analysis. Our results showed that the group submitted to both ovariectomy and resistance training had significant impact on renal corpuscle components (Bowman's space, renal corpuscle area, and visceral layer), and proximal and distal tubules. Additionally, resistance training, with or without estrogen deprivation, increases creatine phosphokinase and decreases ultrasensitive C-reactive protein. In summary, we suggested that moderate resistance training may be a key factor to maintain the kidney structure and function across age. However, future studies are need to corroborate with our findings.

MicroRNA molecules as predictive biomarkers of adaptive responses to strength training and physical inactivity in haemodialysis patients

The miRNA-206 and miRNA-23a play an important role in muscle tissue hypertrophy, regeneration and atrophy. Both of these miRNAs have been highlighted as promising adaptation predictors; however, the available evidence on associations is inconclusive. Therefore, our aim was to assess the expression levels of these two miRNAs as predictors of change in muscle function during strength training and physical inactivity among dialysed patients. For this purpose, 46 haemodialysis patients were monitored for 12-weeks of either intradialytic strength training (EXG, n = 20) or physical inactivity during dialysis (CON, n = 26). In both groups of patients, we assessed the baseline expression levels of miRNA-23a and miRNA-206 and the isometric force generated during hip flexion (HF) contraction before and after the 12-week period. Among the EXG group, the expression of miRNA-206 predicted the change in HF (R² = 0.63, p = 0.0005) much more strongly than the expression of miRNA-23a (R² = 0.21, p = 0.027). Interestingly, baseline miRNA-23a (R² = 0.30, p = 0.006) predicted the change in HF much more than miRNA-206 (p = ns) among the CON group. Our study indicates that the baseline expression of miRNA-206 could predict the response to strength training, while miRNA-23a could serve as a potential predictive marker of functional changes during physical inactivity in dialysis patients.

Functional training added to intradialytic cycling lowers low-density lipoprotein cholesterol and improves dialysis adequacy: a randomized controlled trial

Background

Exercise has various positive effects on hemodialysis patients. However, there is no clear evidence which type of exercise yields better results. This study aimed to determine the effects of guided functional training added to the intradialytic cycling on dialysis adequacy and biochemical parameters in hemodialysis patients. Additionally, we aimed to investigate if patients could transfer functional exercise to an unsupervised home environment and retain gained improvements.

Methods

Randomization was done to a functional training intervention group (INT) (n = 20) or intradialytic cycling control group (CON) (n = 20). The INT attended a pre-dialysis functional training in the first 8 weeks. In the second 8 weeks, they performed functional exercises at unsupervised home environment on non-dialysis days. During the whole study, both groups participated in the intradialytic cycling program.

Results

Both groups demonstrated a significant increase in dialysis adequacy (Kt/V) in the eight (0.15, 95% CI 0.06 to 0.24; p = 0.003 for INT and 0.21, 95% CI 0.11 to 0.3; p < 0.001 for CON) and the 16th study week (0.13, 95% CI 0.03 to 0.24; p = 0.017 for INT and 0.13, 95% CI 0.03 to 0.22; p = 0.013 for CON) compared to their baseline values with no significant between-group differences. At week eight, the total cholesterol was significantly lowered in the INT (− 0.34 mmol/L, 95% CI − 0.6 to − 0.07; p = 0.016) and remained lower at week 16 (− 0.32 mmol/L, 95% CI − 0.64 to − 0.01; p = 0.049) with no significant changes in the CON. Low-density lipoprotein levels in the INT were significantly reduced after 8 weeks (− 0.35 mmol/L, 95% CI − 0.64 to − 0.06; p = 0.022) and remained reduced after 16 weeks (− 0.28 mmol/L, 95% CI − 0.52 to − 0.03; p = 0.030). There were no significant differences found for albumin, high-density lipoprotein cholesterol, triglycerides, C-reactive protein, and hemoglobin in both groups.

Conclusions

We demonstrated that functional training added to intradialytic cycling improved lipid profile and dialysis adequacy. Additionally, the effects of the unsupervised, home-based program were preserved during the second study phase. This study supports the assumption that combined training is more effective compared to solely intradialytic exercise.

Trial registration

ClinicalTrials.Gov, NCT03334123. Registered 07 November 2017.

Uremic Sarcopenia: Clinical Evidence and Basic Experimental Approach

Sustained physical activity extends healthy life years while a lower activity due to sarcopenia can reduce them. Sarcopenia is defined as a decrease in skeletal muscle mass and strength due not only to aging, but also from a variety of debilitating chronic illnesses such as cancer and heart failure. Patients with chronic kidney disease (CKD), who tend to be cachexic and in frail health, may develop uremic sarcopenia or uremic myopathy due to an imbalance between muscle protein synthesis and catabolism. Here, we review clinical evidence indicating reduced physical activity as renal function deteriorates and explore evidence-supported therapeutic options focusing on nutrition and physical training. In addition, although sarcopenia is a clinical concept and difficult to recapitulate in basic research, several in vivo approaches have been attempted, such as rodent subtotal nephrectomy representing both renal dysfunction and muscle weakness. This review highlights molecular mechanisms and promising interventions for uremic sarcopenia that were revealed through basic research. Extensive study is still needed to cast light on the many aspects of locomotive organ impairments in CKD and explore the ways that diet and exercise therapies can improve both outcomes and quality of life at every level.

The effects of an intradialytic resistance training on lower extremity muscle functions

Purpose: The loss of muscle functions is a significant health issue among dialysis patients. Poor muscle strength negatively affects a patient's mobility, independence and quality of life. The aim of the study was to assess the effects of an intradialytic resistance training (IRT) on lower extremity muscle functions among dialysed patients.Materials and methods: Ninety patients were allocated into an experimental group (n = 57) or control group (CNG) (n = 33) according to the location of the dialysis service center. Fifty-eight patients completed the study follow-up. The intervention regarded 12-week IRT, while the controls remained physically inactive during hemodialysis. In both groups of patients, we assessed lower extremity muscle functions by a diagnostics of maximal isometric force generated during hip flexion (HF), hip extension (HE), and knee extension (KE) contractions at baseline, after the 12-weeks intervention and after a further 12-weeks follow up.Results: We found that improvements in HE between baseline and post-intervention were significantly larger for the experimental than the CNG (difference 32.0, 95% CI = 12.3-51.8, p = 0.002). For the other primary outcomes, we found no differences between the groups, and neither for the two other indices of muscle strength (HF and KE). At 12-weeks follow-up, we found no statistically significant differences between the two groups.Conclusions: Our findings indicate that exercise during dialysis not just suppresses adverse effects in muscle strength and functioning, but effectively and safely increases lower extremities muscle function in a relatively short time.Implications for RehabilitationRegular, progressive, resistance training realized during dialysis is well tolerated and safe for exercise interventions in hemodialysis patients.A 12-weeks intradialytic resistance training is effective in the prevention and clinical management of muscle function loss among hemodialysis patients.The range of improvements in muscle functions, demonstrated by the assessment of maximal isometric force, varied severely during different lower extremity movements of hemodialysis patients.

Resistance Training Increases Muscle Strength and Muscle Size in Patients With Liver Cirrhosis

BACKGROUND & AIMS

Cirrhosis is often complicated by reduced muscle mass and strength, which limits the ability to perform daily activities and affects quality of life. Resistance training can increase muscle strength and mass in elderly and chronically ill patients. We performed a randomized controlled trial to investigate whether resistance training increases muscle strength and size in patients with compensated cirrhosis.

METHODS

We performed a prospective study of 39 patients with cirrhosis (Child-Pugh class A or B) seen at an outpatient clinic in Denmark from January 2015 through March 2017. Participants protein intake and activity levels were registered daily. Participants were randomly assigned (1:1) to a group that performed 36 1-hour sessions of physical exercise (supervised progressive resistance training for 1 hour, 3 times weekly for 12 weeks) or a control group (no change in daily activity level). Maximal muscle strength was measured as the peak torque in isokinetic knee extension and muscle size was measured as the cross-sectional area of the quadriceps muscle, assessed by magnetic resonance imaging of the thigh.

RESULTS

The exercise group increased their muscle strength by 13% (from a mean 119 Nm to 134 Nm)-an 11 Nm greater gain in mean strength than that of the control group (P = .05). The exercise group increased their quadriceps cross-sectional area by 10% (from a mean 58.5 cm² to 64.6 cm²)-a 4.4 cm² greater gain than that of the control group (P < .01). The exercise group had significant increases in whole-body lean mass and body cell mass, and significant increases in 6-minute walking distance and the mental component summary of the short form-36 questionnaire. Adverse events were minor and equal between groups.

CONCLUSIONS

In a randomized trial of patients with compensated cirrhosis, we found that 12 weeks of supervised progressive resistance training increased muscle strength and size and had beneficial effects on general performance measures, compared with patients who did not change their daily activity routine (control subjects). ClinicalTrials.gov no: NCT02343653.

Grip strength in children with chronic kidney disease

BACKGROUND

The relationship between muscle strength and chronic kidney disease (CKD) in children is unknown. This study aims to quantify the association between grip strength (GS) and kidney function and to explore factors associated with grip strength in children and adolescents with CKD.

METHODS

We included 411 children (699 GS assessments) of the Chronic Kidney Disease in Children (CKiD) study. They were matched by age, sex, and height to a healthy control from the National Health and Nutrition Examination Survey to quantify the relationship between GS and CKD. Linear mixed models were used to identify factors associated with GS among CKD patients.

RESULTS

Median GS z-score was - 0.72 (IQR - 1.39, 0.11) among CKD patients with CKD stages 2 through 5 having significantly lower GS than CKD stage 1. Compared with healthy controls, CKiD participants had a decreased GS z-score (- 0.53 SD lower, 95% CI - 0.67 to - 0.39) independent of race/ethnicity and body mass index. Factors associated with reduced GS included longer duration of CKD, pre-pubertal status, delayed puberty, neuropsychiatric comorbidities, need of feeding support, need for alkali therapy, and hemoglobin level. Decreased GS was also associated with both a lower frequency and intensity of physical activity.

CONCLUSIONS

CKD is associated with impaired muscle strength in children independent of growth retardation and BMI. Exposure to CKD for a prolonged time is associated with impaired muscle strength. Potential mediators of the impact of CKD on muscle strength include growth retardation, acidosis, poor nutritional status, and low physical activity. Additional studies are needed to assess the efficacy of interventions targeted at these risk factors.

An Exercise Program for Peritoneal Dialysis Patients in the United States: A Feasibility Study

BACKGROUND

People with end-stage kidney disease receiving peritoneal dialysis (PD) are generally physically inactive and frail. Exercise studies in PD are scarce and currently there are no PD exercise programs in the United States. The primary objective of this study was to test the feasibility of a combined resistance and cardiovascular exercise program for PD patients under the care of a dedicated home dialysis center in the United States.

STUDY DESIGN

Parallel randomized controlled feasibility study.

SETTING & PARTICIPANTS

PD patients were recruited from a single center and randomly assigned to the intervention (exercise; n = 18) or control (nonexercise; n = 18) group.

INTERVENTION

The intervention group received monthly exercise physiologist consultation, exercise prescription (resistance and aerobic exercise program using exercise bands), and 4 exercise support telephone calls over 12 weeks. The control group received standard care.

OUTCOMES

The primary outcome was study feasibility as measured by eligibility rates, recruitment rates, retention rates, adherence rates, adverse events, and sustained exercise rates. Secondary outcome measures were changes in physical function (sit-to-stand test, timed-up-and-go test, and pinch-strength tests) and patient-reported outcome measures.

RESULTS

From a single center with 75 PD patients, 57 (76%) were deemed eligible, resulting in a recruitment rate of 36 (63%) patients. Participants were randomly assigned into 2 groups of 18 (1:1). 10 patients discontinued the study (5 in each arm), resulting in 26 (72%) patients, 13 in each arm, completing the study. 10 of 13 (77%) intervention patients were adherent to the exercise program. A t test analysis of covariance found a difference between the treatment groups for the timed-up-and-go test (P = 0.04) and appetite (P = 0.04). No serious adverse events caused by the exercise program were reported.

LIMITATIONS

Single center, no blinded assessors.

CONCLUSIONS

A resistance and cardiovascular exercise program appears feasible and safe for PD patients. We recommend that providers of PD therapy consider including exercise programs coordinated by exercise professionals to reduce the physical deterioration of PD patients.

FUNDING

None.

TRIAL REGISTRATION

NCT03980795.

Modifiable Physical Factors Associated With Physical Functioning for Patients Receiving Dialysis: A Systematic Review

BACKGROUND

Patients receiving dialysis have reduced physical function, which is associated with unfavorable clinical outcomes and decreased quality of life. The authors aimed to identify and explore modifiable physical factors associated with physical function for patients receiving dialysis.

METHODS

Searches were performed in MEDLINE, Embase, Ovid Emcare, and The Cochrane Library in October 2018. Etiological studies involving dialysis populations that report association or predictive statistics between a modifiable physical factor and physical function were eligible for inclusion. Predictor variables were (1) modifiable via exercise and (2) considered an impairment in the International Classification of Functioning, Disability and Health.

RESULTS

Of 5384 titles screened, 23 studies were included. Thirteen studies focused on physical activity levels and muscle strength and the relationship with physical function while 2 studies investigated sedentary behavior. Twenty-one studies focused on hemodialysis populations. Studies related to physical activity levels displayed a moderately strong relationship with physical function, whereas muscle strength displayed a predominantly weak to moderate relationship.

CONCLUSIONS

Physical activity levels, sedentary behavior levels, and muscle strength are related to physical function status for patients receiving dialysis. There is a need for robust longitudinal data to confirm the results of this investigation and for more focus on populations receiving peritoneal dialysis.

The Adverse Effects of Androgen Deprivation Therapy in Prostate Cancer and the Benefits and Potential Anti-oncogenic Mechanisms of Progressive Resistance Training

Prostate cancer has the second highest incidence of all cancers amongst men worldwide. Androgen deprivation therapy (ADT) remains a common form of treatment. However, in reducing serum testosterone to castrate levels and rendering men hypogonadal, ADT contributes to a myriad of adverse effects which can affect prostate cancer prognosis. Physical activity is currently recommended as synergistic medicine in prostate cancer patients to alleviate the adverse effects of treatment. Progressive resistance training (PRT) is an anabolic exercise modality which may be of benefit in prostate cancer patients given its potency in maintaining and positively adapting skeletal muscle. However, currently, there is a scarcity of RCTs which have evaluated the use of isolated PRT in counteracting the adverse effects of prostate cancer treatment. Moreover, although physical activity in general has been found to reduce relapse rates and improve survival in prostate cancer, the precise anti-oncogenic effects of specific exercise modalities, including PRT, have not been fully established. Thus, the overall objective of this article is to provide a rationale for the in-depth investigation of PRT and its biological effects in men with prostate cancer on ADT. This will be achieved by (1) summarising the metabolic effects of ADT in patients with prostate cancer and its effect on prostate cancer progression and prognosis, (2) reviewing the existing evidence regarding the metabolic benefits of PRT in this cohort, (3) exploring the possible oncological pathways by which PRT can affect prostate cancer prognosis and progression and (4) outlining avenues for future research.

Intradialytic training in patients with end-stage renal disease: a systematic review and meta-analysis of randomized clinical trials assessing the effects of five different training interventions

OBJECTIVE

Patients with end-stage renal disease (ESRD) undergoing hemodialysis may have reduced dialysis adequacy (Kt/V), low cardiorespiratory fitness, and worse prognosis. Different types of intradialytic training (IDT) may serve as an adjunct therapy for the management of the ESRD. This systematic review and meta-analysis aimed to assess the impact of different types of IDT on clinical outcomes and functional parameters in ESRD.

METHODS

PubMed, Embase, CINAHL, Cochrane CENTRAL, Scopus, SPORTDiscus, and Google Scholar were searched for randomized clinical trials in adult patients with ESRD which compared IDT with usual care (UC), without language restrictions and published up to July 2019; a handsearch of references was also performed. Certainty of evidence was assessed using GRADE, and risk of bias in primary studies with the RoB 1.0 tool.

RESULTS

Fifty studies were included (n = 1757). Compared to UC, aerobic IDT improved Kt/V (WMD = 0.08), VO₂peak (WMD = 2.07 mL/kg/min), 6-minute walk test (6MWT) distance (64.98 m), reduced systolic blood pressure (- 10.07 mmHg) and C-reactive protein (- 3.28 mg/L). Resistance training increased 6MWT distance (68.50 m). Combined training increased VO₂peak (5.41 mL/kg/min) and reduced diastolic blood pressure (- 5.76 mmHg). Functional electrostimulation (FES) and inspiratory muscle training (IMT) improved 6MWT distance (54.14 m and 117.62 m, respectively). There was no impact on total cholesterol, interleukin-6, or hemoglobin levels. There was no difference in incidence of adverse events between the IDT and control groups. The certainty of evidence was variable according to the GRADE scale, with most outcomes rated very low certainty. The risk of bias assessment of primary studies showed unclear risk in most.

CONCLUSIONS

Aerobic, resistance, and combined training during hemodialysis, as well as FES and IMT, demonstrated to be effective for the treatment of the patient with ESRD. Our data should be interpreted in light of the unclear risk of bias of most evaluated articles and the low to very low certainty of evidence for evaluated outcomes.

PROSPERO REGISTRATION ID

CRD42017081338. DATA SHARING REPOSITORY: https://osf.io/fpj54/.

Resistance Training for Older Adults: Position Statement From the National Strength and Conditioning Association

Fragala, MS, Cadore, EL, Dorgo, S, Izquierdo, M, Kraemer, WJ, Peterson, MD, and Ryan, ED. Resistance training for older adults: position statement from the national strength and conditioning association. J Strength Cond Res 33(8): 2019-2052, 2019-Aging, even in the absence of chronic disease, is associated with a variety of biological changes that can contribute to decreases in skeletal muscle mass, strength, and function. Such losses decrease physiologic resilience and increase vulnerability to catastrophic events. As such, strategies for both prevention and treatment are necessary for the health and well-being of older adults. The purpose of this Position Statement is to provide an overview of the current and relevant literature and provide evidence-based recommendations for resistance training for older adults. As presented in this Position Statement, current research has demonstrated that countering muscle disuse through resistance training is a powerful intervention to combat the loss of muscle strength and muscle mass, physiological vulnerability, and their debilitating consequences on physical functioning, mobility, independence, chronic disease management, psychological well-being, quality of life, and healthy life expectancy. This Position Statement provides evidence to support recommendations for successful resistance training in older adults related to 4 parts: (a) program design variables, (b) physiological adaptations, (c) functional benefits, and (d) considerations for frailty, sarcopenia, and other chronic conditions. The goal of this Position Statement is to a) help foster a more unified and holistic approach to resistance training for older adults, b) promote the health and functional benefits of resistance training for older adults, and c) prevent or minimize fears and other barriers to implementation of resistance training programs for older adults.

Dietary Protein and Physical Activity Interventions to Support Muscle Maintenance in End-Stage Renal Disease Patients on Hemodialysis

End-stage renal disease patients have insufficient renal clearance capacity left to adequately excrete metabolic waste products. Hemodialysis (HD) is often employed to partially replace renal clearance in these patients. However, skeletal muscle mass and strength start to decline at an accelerated rate after initiation of chronic HD therapy. An essential anabolic stimulus to allow muscle maintenance is dietary protein ingestion. Chronic HD patients generally fail to achieve recommended protein intake levels, in particular on dialysis days. Besides a low protein intake on dialysis days, the protein equivalent of a meal is extracted from the circulation during HD. Apart from protein ingestion, physical activity is essential to allow muscle maintenance. Unfortunately, most chronic HD patients have a sedentary lifestyle. Yet, physical activity and nutritional interventions to support muscle maintenance are generally not implemented in routine patient care. To support muscle maintenance in chronic HD patients, quantity and timing of protein intake should be optimized, in particular throughout dialysis days. Furthermore, implementing physical activity either during or between HD sessions may improve the muscle protein synthetic response to protein ingestion. A well-orchestrated combination of physical activity and nutritional interventions will be instrumental to preserve muscle mass in chronic HD patients.

Cachexia/Protein energy wasting syndrome in CKD: Causation and treatment

Cachexia is a multifactorial syndrome defined by significant body weight loss, fat and muscle mass reduction, and increased protein catabolism. Protein energy wasting (PEW) is characterized as a syndrome of adverse changes in nutrition and body composition being highly prevalent in patients with CKD, especially in those undergoing dialysis, and it is associated with high morbidity and mortality in this population. Multiple mechanisms are involved in the genesis of these adverse nutritional changes in CKD patients. There is no obvious distinction between PEW and cachexia from a pathophysiologic standpoint and should be considered as part of the spectrum of the same nutritional disorder in CKD with similar management approaches for prevention and treatment based on current understanding. A plethora of factors can affect the nutritional status of CKD patients requiring a combination of therapeutic approaches to prevent or reverse protein and energy depletion. At present, there is no effective pharmacologic intervention that prevents or attenuates muscle atrophy in catabolic conditions like CKD. Prevention and treatment of uremic muscle wasting involve optimal nutritional support, correction of acidosis, and physical exercise. There has been emerging consistent evidence that active treatment, perhaps by combining nutritional interventions and resistance exercise, may be able to improve but not totally reverse or prevent the supervening muscle wasting and weakness. Active research into more direct pharmacological treatment based on basic mechanistic research is much needed for this unmet medical need in patients with CKD.

Intradialytic exercise with blood flow restriction is more effective than conventional exercise in improving walking endurance in hemodialysis patients: a randomized controlled trial

OBJECTIVE

This study aims to compare the effect of intradialytic aerobic exercise with blood flow restriction, without blood flow restriction (conventional) and no exercise (control) on muscle strength and walking endurance among chronic kidney disease patients.

DESIGN

Open label and parallel group randomized controlled trial.

SUBJECTS

Adult patients with chronic kidney disease on hemodialysis.

INTERVENTION

A 12-week intradialytic training with or without blood flow restriction compared with a control group.

MAIN MEASURES

Strength and walking endurance were measured using thoracolumbar dynamometry and a 6-minute walk test, respectively, before and after training.

RESULTS

A total of 66 patients were randomized into three groups: blood flow restriction group (n = 22), conventional exercise group (n = 22) and control group (n = 22). There were seven dropouts, and 59 patients were included in the analysis. There was a significant increase in the 6-minute walking distance in the blood flow restriction group (from 412.7 (115.9) to 483.0 (131.0) m, P = 0.007) in comparison with the conventional exercise group (from 426.79 (115.00) to 433.2 (120.42) m, not significant) and the control group (from 428.4 (108.1) to 417.3 (100.2) m, not significant). The change in the walking distance over time was significantly different among groups (intervention group/time, P = 0.02). The simple effects test found a significant time effect only in the blood flow restriction group. There was no significant difference in strength change between the groups.

CONCLUSION

Among chronic kidney disease patients, intradialytic exercise of low/moderate intensity with blood flow restriction was more effective in improving walking endurance than conventional exercise or no exercise.

Effect of Oral Nutritional Supplementation With and Without Exercise on Nutritional Status and Physical Function of Adult Hemodialysis Patients: A Parallel Controlled Clinical Trial (AVANTE-HEMO Study)

OBJECTIVE

Protein energy wasting affects the nutritional status (NS) and physical function (PF) of dialysis patients. Among the different anabolic strategies to improve NS and PF, oral nutritional supplementation (ONS) and resistance exercise (RE) or aerobic exercise (AE) have been shown to be effective. Nevertheless, the combination of both anabolic strategies has not been completely evaluated. The aim of this study is to assess the effect of exercise combined with ONS versus ONS without exercise during hemodialysis sessions on PF and NS indicators.

METHODS

Young hemodialysis patients (29 ± 9.3 years) with predominantly unknown causes of renal disease (80%) were divided into the following 3 groups during a period of 12 weeks: (1) ONS (n = 15), (2) ONS + RE (n = 15), and (3) ONS + AE (n = 15). Anthropometric, biochemical, PF, and quality of life measurements were recorded at baseline and after 3 months. Repeated measures analysis of variance and effect sizes (Cohen's d) were used to assess the effect of exercise and nutrition (ISRCTN registry 10251828).

RESULTS

At the completion of the study, the ONS and ONS + RE groups exhibited statistically significant increases in body weight, body mass index, and in the percentage of fat mass (P < .05); the greatest effect sizes were observed in the ONS + RE group (d = 0.30 for body weight, d = 0.63 for body mass index, and d = 0.90 for the percentage of fat mass). Groups with RE and AE had statistically significant increases and large effect sizes in the six-minute walk test (RE: d = 0.94, P = .02; AE: d = 1.11, P = .03), sit-to-stand test (RE: d = 0.81, P = .041; AE: d = 1.20, P = .002), timed up and go test (RE: d = 1.04, P = .036; AE: d = 1.6, P = .000), and muscle strength (RE: d = 1.01, P = .000; AE: d = 0.60, P = .003). Regarding quality of life, the ONS + RE group had more areas of improvement at the end of the study, followed by the ONS + AE group. No statistically significant differences were found in the repeated measures ANOVA.

CONCLUSIONS

The combination of exercise with ONS had larger effects on PF than on ONS alone. Further studies to examine the impact of exercise on the effect of oral nutritional supplementation in dialysis patients are indicated.

LIFESTYLE RISK FACTORS AND BONE MASS IN RECURRENT STONE-FORMING PATIENTS: A CROSS-SECTIONAL STUDY IN 144 SUBJECTS

Patients with urolithiasis, particularly hypercalciuria, may have reduced bone mineral density (BMD). There are numerous risk factors contributing to reduction of BMD such as advanced age, sedentary lifestyle, smoking, low calcium intake, etc. The aim of our study was to investigate the association of lifestyle risk factors and daily intake of milk and dairy products with determinants of BMD in a group of recurrent calcium stone formers (RSF) compared with healthy subjects (HS). The study was carried out at the Department of Mineral Research, Faculty of Medicine in Osijek, Croatia. The study included 144 subjects, i.e. 56 RSF and 78 HS. BMD was assessed by dual-energy x-ray absorptiometry. A standard self-reported questionnaire was used to collect data on lifestyle risk factors. Current dietary intake was assessed by personal interview that included questions about milk and dairy product intake. Low BMD was observed in 44.64% of RSF and 35.90% of HS. RSF consumed significantly less milk and dairy products than HS. Calcium restriction in dietary recommendations might be unnecessary due to the impact on bone mineral loss in RSF and dual-energy x-ray absorptiometry should be included in the routine evaluation of RSF.

Intradialytic Resistance Training Improves Functional Capacity and Lean Mass Gain in Individuals on Hemodialysis: A Randomized Pilot Trial

OBJECTIVE

To compare the effects of high vs moderate loads of intradialytic resistance training (RT) on body composition, sarcopenia prevalence, functional capacity, inflammatory markers, and quality of life (QoL) in individuals on hemodialysis.

DESIGN

A pilot randomized clinical trial.

SETTING

Two hemodialysis centers.

PARTICIPANTS

Individuals on hemodialysis (N=80; 51% men, aged 30-75y) in treatment for at least 3 months, adequately dialyzed (Kt/V≥1.2, where K is dialyzer clearance in mL/min, t is time, and V is volume of water) with vascular access via arteriovenous fistula.

INTERVENTIONS

The 12 weeks of intradialytic RT was performed 3 times per week. The training groups were: high-load intradialytic group (HLG, 8-10 repetitions), moderate-load intradialytic group (MLG, 16-18 repetitions), and control group (CG, stretching exercise). The total training volume was equalized among training groups.

MAIN OUTCOME MEASURES

Lean leg mass was assessed by a dual-energy x-ray absorptiometry; functional capacity was assessed by Short Physical Performance Battery and Timed Up and Go test; and QoL was assessed by Kidney Disease QoL Instrument, inflammatory markers, and sarcopenia.

RESULTS

After the training period, the HLG increased lean leg mass compared with the CG. The HLG also displayed improvements in the pain and physical function domains. The skeletal muscle index and functional capacity increased in both RT protocols. The prevalence of sarcopenia was reduced 14.3% and 25% in the MLG and HLG, respectively, while there was an increase of 10% in the CG. No differences were observed in cytokines after intervention.

CONCLUSIONS

High-load intradialytic RT was associated with gains in lean leg mass and QoL while functional capacity, appendicular muscle mass, and sarcopenia status were improved regardless of the RT load.

The role of exercise in improving patient-reported outcomes in individuals on dialysis: A scoping review

Exercise improves objective measures of physical function in individuals on hemodialysis, but its effect on patient-reported outcomes (PROs) is largely unknown. We performed a scoping review to characterize the existing knowledge base on exercise and PROs in dialysis patients to make recommendations for future research. We searched Medline, Embase, Cochrane Database of Systematic Reviews; Cochrane Central Register of Controlled Trials, CINAHL, and SPORT Discus from inception to November 28, 2018 and then screened results for randomized controlled trials comparing aerobic/resistance exercise, or both, with no exercise in individuals on dialysis that reported results of any PRO. Of 1374 eligible studies, 25 studies met inclusion criteria. Study interventions included aerobic exercise (11 intradialytic and 3 home-based trials); intradialytic resistance exercise (seven studies) and combined aerobic and resistance exercise (six intradialytic and one facility-based trial). The PROs measured included health-related quality of life (n = 19), depression (n = 6), anxiety (n = 3), symptom burden (n = 4), sleep quality (n = 2), restless legs syndrome (n = 2), disability (n = 2), and self-reported physical activity level (n = 4). Only five studies included a PRO as a primary outcome. Studies primarily used broad/generic measures of health-related quality of life and the effect of exercise on symptoms remains relatively unexplored, particularly in peritoneal dialysis populations. Although limited, the role of exercise in improving restless legs was consistent and is a promising outcome for future study. A critical step to improving the quality of the research on this topic includes the use of validated and consistent PRO measures.

Effect of exercise therapy on physical performance and functional balance in patients on maintenance renal hemodialysis: randomized controlled study

Physical performance (PP) and functional balance (FB) abnormalities are frequently encountered problems in patients on maintenance renal hemodialysis (MRH). Although the exercise therapy is an adjunctive to the routine medical care for patients with chronic kidney disease of various stages; but the benefits as well as the long-term effects of different exercises on the PP and FB in patients on MRH are not yet fully described. In this study; Sixty-six patients on MRH (36 males, 30 females), age 35–45 years, were randomly assigned into one of the three groups: aerobic exercise training group (AETG), resistance exercise training group (RETG), and control group (CG). The PP (evaluated using the 6-min walk test “6MWT”) and the FB (evaluated via the Berg balance scale “BBS”) were the main study outcomes evaluated prestudy (evaluation-1), after 3 months (evaluation-2) and 2 months poststudy cessation (evaluation-3). Results revealed that the PP and FB mean values and percentages of changes at evaluation-2 were 444.25±21.83 (33.1%), 413.57±28.55 (22.52%), 337±12.23 (0.33%) m, 50.05±0.89 (22.95%), 49.95±2.06 (22.52%), 41.28±1.75 (0.94%) for AETG, RETG, and CG respectively. At evaluation-3; the PP and FB mean values and the percentage of changes were 425±21.49 (27.36), 366.86±17.47 (8.5%), 336.68 (0.42%) m, 44.4±1.85 (8.06%), 42.95±2.04 (5.003%), 39.48±2.06 (−4.44%) for AETG, RETG, and CG respectively. In conclusions; both aerobic exercise training (AET) and resistance exercise training (RET) have favorable effects, with the AET has higher short and long-term favorable effects on the PP and FB than RET in patients on MRH.

Nonpharmacological Interventions for Depressive Symptoms in End-Stage Renal Disease: A Systematic Review

Depressive symptoms are common in patients with end-stage renal disease, which can affect treatment and prognosis. We aimed to evaluate the effects of nonpharmacological interventions for depressive symptoms in end-stage renal disease. Eligible studies were identified using PubMed, Web of Science, the Cochrane Library, Embase, and PsycNET (up to March 2019). We identified 24 studies including 1,376 patients. We found that psychological intervention (-0.60, 95% confidence interval [CI] = [-0.87, -0.33]), exercise (-1.13, 95% CI = [-1.56, -0.69]), and manual acupressure (-0.26, 95% CI = [-0.50, 0.03]) were associated with a significant effect on depressive symptoms. However, few studies reported adverse events, and conclusions about safety should be drawn cautiously. While the available data show that nonpharmacological interventions are potential strategies to alleviate depressive symptoms of patients with end-stage renal disease, recommendation of the most efficacious interventions for this population will require future randomized controlled trials with large-scale, long-term intervention.

A randomized controlled trial of exercise to prevent muscle mass and functional loss in elderly hemodialysis patients: Rationale, study design, and baseline sample

Background

Elderly maintenance hemodialysis (MHD) patients exhibit muscle wasting and impaired physical function. This trial determines whether MHD patients benefit from a 12-week home-based exercise program, protein supplementation, or both.

Design

and Methods: This is a randomized, blinded controlled trial involving 60 elderly MHD patients with impaired exercise capacity and function. Patients are randomized into either a homebased exercise program or normal care over a 12-week period. Measures at baseline include peak VO₂, strength and body composition as well as cognitive and disease-specific questionnaires. Muscle biopsies are obtained and analyzed for protein signaling, expression of IGF-1, androgen receptors, and myostatin.

Results

At baseline, patient characteristics in the exercise and normal care groups were similar by age, gender and anthropomorphic measures. Peak VO₂ was impaired (14.7 ± 3.3 ml/kg/min), representing 55 ± 14% of the age-predicted value. Six-minute walk distance was 322 ± 71 m, and the mean 1-min sit to stand test was 18 ± 8 repetitions, representing 69 ± 16% and 55 ± 22% of the age-predicted values, respectively. Indices of muscle function, including upper and lower body and hand grip strength all indicate marked impairment. Quality of life (QoL) using the SF36, the Beeson cognitive test, and KDQOL all suggest marked impairments compared to age-expected reference values for non-MHD patients.

Conclusions

Patients undergoing MHD exhibit markedly reduced physical function and QoL. Thus, there are potentially significant gains to be made through a program of aerobic and resistance exercise. We anticipate this trial will demonstrate that home-based exercise improves cardiopulmonary function, protein signaling and QoL, and increases muscle mass, strength, and body composition.

Quantitative Assessment of Muscular Stiffness in Children With Chronic Kidney Disease Using Acoustic Radiation Force Impulse Ultrasound Elastography

ABSTRACT

The aim of this study was to evaluate the feasibility of quantitative analysis of muscle stiffness in the rectus femoris muscle (RFM) by acoustic radiation force impulse (ARFI) ultrasound elastography in children with chronic kidney disease (CKD). Twenty-three children with CKD and 22 healthy children participated in the study in our radiology department. The strength of each CKD group and healthy group participants' tight extensors was assessed by a physiatrist using a handheld dynamometer. Acoustic radiation force impulse was used to measure the shear wave velocities (SWVs) of the RFM. The mean SWV value of the RFM correlated with the strengths of the tight extensors in the CKD and healthy groups. The mean ± SD SWV values of the RFM in the CKD group for the right (n = 23) and left sides (n = 21) were 1.23 ± 0.25 and 1.26 ± 0.30 m/s, respectively. The mean ± SD SWV values of the RFM in the healthy group for the right (n = 23) and left sides (n = 21) were 1.62 ± 0.33 and 1.65 ± 0.35 m/s, respectively. The SWV of the RFM significantly decreased in the patients with CKD when compared with controls (P < 0.001). The SWV values were not correlated to the handheld dynamometry. The interobserver agreement expressed as the interclass correlation coefficient was 0.65 (95% confidence interval, 0.33-0.84; P < 0.001). The acoustic radiation force impulse demonstrates a difference in RFM muscle stiffness between the CKD and healthy groups. This method is a feasible imaging method for the noninvasive assessment of muscle weakness in children with CKD.

The association between six month intra-dialytic resistance training and muscle strength or physical performance in patients with maintenance hemodialysis: a multicenter retrospective observational study

Background

Reduced muscle strength and physical performance are prevalent in patients of maintenance hemodialysis (MHD), and deleterious changes in these parameters are associated with increased mortality.

Methods

This retrospective observational study included 306 patients, who received a 6-month resistance exercise program during hemodialysis, three times per week on an outpatient basis. The training protocol consisted of two sets of 10 repetitions of knee extension, hip abduction, and hip flexion, using an elastic band in a sitting or supine position. Primary outcome measures included muscle strength, measured by percent knee extension muscle power to dry body weight (pKEMP-dBW), and physical performance, measured by short physical performance battery (SPPB). The adjusted mean differences in these variables during the 6 months were estimated using a multivariate linear regression model.

Results

The mean age with standard deviation was 70 ± 11 years. One hundred and sixty patients (52.3%) were men and the dry weight was 55.6 ± 11.3 kg. Sarcopenia, defined as SPPB ≤8, was present in 21.4% patients. Their hemodialysis adequacy was acceptable, with a Kt/V of 1.65 ± 0.29, and their nutritional status was good, with a normalized protein catabolism rate of 0.89 ± 0.18 g/kg/day. During the 6 months, both pKEMP-dBW and SPPB showed a slight but significant increase with an adjusted mean difference of 2.8 (95% confidence interval 1.3–4.3, p <  0.001) and 0.6 (0.4–0.9, p <  0.001), respectively.

Conclusions

Six-month resistance training was associated with improved muscle strength and physical performance in patients with MHD.

Exercise interventions for improving objective physical function in patients with end-stage kidney disease on dialysis: a systematic review and meta-analysis

Patients with end-stage kidney disease on dialysis have increased mortality and reduced physical activity, contributing to impaired physical function. Although exercise programs have demonstrated a positive effect on physiological outcomes such as cardiovascular function and strength, there is a reduced focus on physical function. The aim of this review was to determine whether exercise programs improve objective measures of physical function indicative of activities of daily living for patients with end-stage kidney disease on dialysis. A systematic search of Medline, Embase, the Cochrane Central Register of Controlled Trials, and Cumulative Index to Nursing and Allied Health Literature identified 27 randomized control trials. Only randomized control trials using an exercise intervention or significant muscular activation in the intervention, a usual care, nonexercising control group, and at least one objective measure of physical function were included. Participants were ≥18 yr of age, with end-stage kidney disease, undergoing hemo- or peritoneal dialysis. Systematic review of the literature and quality assessment of the included studies used the Cochrane Collaboration’s tool for assessing risk bias. A meta-analysis was completed for the 6-min walk test. Data from 27 studies with 1,156 participants showed that exercise, regardless of modality, generally increased 6-min walk test distance, sit-to-stand time or repetitions, and grip strength as well as step and stair climb times or repetitions, dynamic mobility, and short physical performance battery scores. From the evidence available, exercise, regardless of modality, improved objective measures of physical function for end-stage kidney disease patients undergoing dialysis. It is acknowledged that further well-designed randomized control trials are required.

The effects of intradialytic resistance training on muscle strength, psychological well-being, clinical outcomes and circulatory micro-ribonucleic acid profiles in haemodialysis patients: Protocol for a quasi-experimental study

BACKGROUND

Intradialytic resistance training (IRT) protects patients' muscle mass and functions against protein-energy wasting, malnutrition and cachexia. However, the evidence of the effects of such an intervention in haemodialysis patients is limited and not conclusive. To improve the applicability of such interventions, we need a better understanding of molecular, functional and psycho-social adaptation in dialysed patients following a physical training. Therefore, the aim of this study is to investigate the effects of IRT on lower extremity muscle functions, quality of life, and anxiety and depression, clinical outcomes and circulatory micro-ribonucleic acid (miRNA) profiles in patients on chronic haemodialysis therapy.

METHODS

We will perform a quasi-experimental study in 3 dialysis centres. Patients will be recruited via their nephrologists and will be allocated to an experimental and a control group based on the location of the patients' dialysis centre. Patients allocated to the experimental group will undergo a 12-week IRT, while the control group will remain physically inactive during dialysis. The primary outcome is the change in the maximal force produced during an isometric contraction of lower extremity muscles. Secondary outcomes regard quality of life, anxiety and depression, clinical outcomes and circulatory miRNA profiles. Patients' level of health literacy defined as the ability to get and understand health information will be also measured in the study as a potential modifier of effects.

DISCUSSION

This quasi-experimental study can add in an important way to our understanding of the effects of resistance training on dialysis patients' muscle strength, quality of life and disease-specific outcomes.

Effects of intradialytic resistance training on physical activity in daily life, muscle strength, physical capacity and quality of life in hemodialysis patients: a randomized clinical trial

Purpose: We evaluated the effects of supervised intradialytic resistance training on physical activity in daily life (PADL), muscle strength, physical capacity and quality of life (QoL) in hemodialysis patients.Methods: Twenty-four hemodialysis patients were randomly assigned to either a 12-weeks moderate-intensity resistance training or a control period. An accelerometer evaluated PADL for seven consecutive days, measuring the time spent in different activities and positions of daily routine and the number of steps taken. Muscle strength, physical capacity and QoL were evaluated.Results: After 12 weeks of training, we did not find significant difference (post-pre values) in walking time (-1.2 ± 18.3 vs. -9.2 ± 13.1 min/day); standing time (-10.2 ± 28.6 vs. 3.2 ± 20.1 min/day); sitting time (20.8 ± 58.9 vs. -30.0 ± 53.0 min/day); lying down time (-9.3 ± 57.9 vs. 34.6 ± 54.0 min/day); number of steps taken [-147 (1834) vs. -454 (2066)] and muscle strength in training and control group, respectively. There was a significant increase in the six-minute walking test distance (48.8 ± 35.9 vs. 6.9 ± 45.9 m, p < 0.05) and some domains of QoL in the training compared to the control group.Conclusions: PADL was not modified after 12 weeks of intradialytic resistance training in hemodialysis patients. However, the exercise program was able to increase the physical capacity and some domains of QoL.Implications for rehabilitationPhysical activity in daily life was not modified after 12 weeks of intradialytic resistance training in hemodialysis patients.The exercise program was able to increase the physical capacity, efficacy of dialysis and some domains of quality of life in hemodialysis patients.The protocol used in this study was safe since no complications were observed during and after resistance training.These results should be interpreted with caution because we applied a moderate resistance training in both lower limbs and in the contralateral arteriovenous fistula upper limb, using perceived exertion by Borg scale to exercise prescription. Moreover, the safety protocol evaluation was not conducted.

Are dialysis patients too frail to exercise?

Clinical manifestations of functional and morphological muscular abnormalities in dialysis patients are muscle weakness and low exercise capacity, possibly leading to a sedentary life style with low physical activity. Low cardiorespiratory fitness and muscle atrophy and weakness contribute to the development of frailty and affect patients' ability to physically navigate their environment. While many dialysis patients may appear too frail to participate in moderate-to-vigorous aerobic exercise training, those who can complete such programs appear to derive substantial benefit. Less vigorous aerobic exercise, resistance training, and alternative forms of exercise can also be beneficial. Most patients on dialysis are not too frail to perform resistance exercise of adequate intensity to achieve increases in muscle size and strength, therefore, frailty should not be considered a contraindication to exercise.

Results from the randomized controlled IHOPE trial suggest no effects of oral protein supplementation and exercise training on physical function in hemodialysis patients

Few long-term studies have assessed whether changes in both diet and exercise can improve the health and quality of life (QOL) of hemodialysis (HD) patients. Here we examined whether 12 months of intradialytic protein supplementation and endurance exercise improves physical function, risk of cardiovascular disease (CVD), and QOL in HD patients in a randomized controlled trial (RCT). A total of 138 HD patients (average age 58 years) were assigned for 12 months to control, intradialytic protein, or protein plus exercise groups. The protein and protein plus exercise groups consumed an oral protein supplement (30 grams of whey) three days/week during dialysis. The protein plus exercise group cycled for 30-45 minutes during dialysis treatment. The primary outcome was change in physical function at 12 months, assessed by a shuttle walk test. Secondary outcomes included arterial stiffness, blood pressure, body composition, muscle strength, markers of nutritional status, and QOL. Assessments were conducted at baseline, 6 and 12 months. In total, 101 patients completed the intervention. There were no significant differences between groups in shuttle walk test performance from baseline to 12 months. There were trends for improvements in some secondary measures of physical function and strength in the protein and protein plus exercise groups at six or 12 months, but these did not reach statistical significance. Thus, our trial did not demonstrate significant improvements in markers of physical function, risk of CVD or QOL after one year of intradialytic oral OPS and aerobic exercise training. More comprehensive lifestyle management may be needed to uncover robust improvements in the health and QOL of HD patients.

Exercise interventions on patients with end-stage renal disease: a systematic review

Objective:

This study aimed to conduct an up-to-date systematic review of the literature to evaluate the effects of exercise on fatigue, anxiety, depression, physical activity, and quality of life (QOL) in patients with end-stage renal disease.

Data sources:

We searched PubMed (October 2018), Embase (from 1966 to October 2018), Web of Science (from 1900 to October 2018), The Cochrane Library (October 2018), and references of papers.

Methods:

This study includes randomized controlled trials that analyzed the combined effects of exercise intervention on patients with end-stage renal disease. Two reviewers independently screened the retrieved records, extracted data, and assessed the risk of bias for inclusion in the study. The effects of exercise intervention were conducted in the meta-analysis using RevMan 5.3 software.

Results:

A total of 614 participants were included in 13 randomized controlled studies. The study revealed that exercise can improve fatigue, anxiety, depression, physical activity, and QOL. The effect value results were as follows: (1) fatigue, −0.97 (95% confidence interval (CI) −1.32 to −0.62, P < 0.00001); (2) anxiety, −0.78 (95% CI −1.17 to −0.39, P < 0.0001); (3) depression, −0.85 (95% CI −1.13 to −0.56, P < 0.00001) (4) physical activity, 38.15 (95% CI 21.20 to 55.10, P < 0.0001); (5) QOL, the physical component of the 36-item Short-Form Health Survey (SF-36), 4.73 (95% CI 1.92 to 7.54, P = 0.0010); and (6) the mental component of the SF-36, 3.42 (95% CI 0.27 to 6.56, P = 0.03).

Conclusion:

Exercise intervention is more effective in fatigue, anxiety, depression, physical activity, and QOL. However, large-scale randomized controlled trials are needed to confirm the appropriate types of exercise and optimal time for patients with end-stage renal disease.

Combined training is the most effective training modality to improve aerobic capacity and blood pressure control in people requiring haemodialysis for end-stage renal disease: systematic review and network meta-analysis

QUESTIONS

Do aerobic, resistance and combined exercise training improve aerobic capacity, arterial blood pressure and haemodialysis efficiency in people requiring haemodialysis for end-stage renal disease? Is one exercise training modality better than the others for improving these outcomes?

DESIGN

Systematic review with network meta-analysis of randomised trials.

PARTICIPANTS

Adults requiring haemodialysis for end-stage renal disease.

INTERVENTION

Aerobic training, resistance training, combined training and control (no exercise or placebo).

OUTCOME MEASURES

Aerobic capacity, arterial blood pressure at rest, and haemodialysis efficiency.

RESULTS

Thirty-three trials involving 1254 participants were included. Direct meta-analyses were conducted first. Aerobic capacity improved significantly more with aerobic training (3.35 ml/kg/min, 95% CI 1.79 to 4.91) and combined training (5.00 ml/kg/min, 95% CI 3.50 to 6.50) than with control. Only combined training significantly reduced systolic (-9 mmHg, 95% CI -13 to -4) and diastolic (-5 mmHg, 95% CI -6 to -3) blood pressure compared to control. Only aerobic training was superior to control for haemodialysis efficiency (Kt/V 0.11, 95% CI 0.02 to 0.20). However, when network meta-analysis was conducted, there were some important different findings. Both aerobic training and combined training again elicited greater improvements in aerobic capacity than control. For systolic blood pressure, combined training was superior to control. For diastolic blood pressure, combined training was superior to aerobic training and control. No modality was superior to control for haemodialysis efficiency. Combined training was ranked as the most effective treatment for aerobic capacity and arterial blood pressure.

CONCLUSION

Combined training was the most effective modality to increase aerobic capacity and blood pressure control in people who require haemodialysis. This finding helps to fill the gap created by the lack of head-to-head comparisons of different modalities of exercise in people with end-stage renal disease.

REGISTRATION

PROSPERO CRD42015020531.