The Effects of Exercise Training Interventions on Dialysis Patients: A Narrative Review of Current Knowledge and Future Perspectives

Abstract

Chronic diseases are a growing concern in aging populations, with physical inactivity playing a major role in their onset and progression. Chronic kidney disease (CKD), which affects approximately 15% of U.S. adults and over 500 million people worldwide, is strongly associated with sedentary behavior. Despite mounting evidence supporting the benefits of exercise training in CKD management, current treatment approaches remain largely pharmacological, with exercise interventions receiving limited emphasis. One challenge is the uncertainty surrounding the most appropriate exercise modalities for CKD patients, particularly those undergoing dialysis. Recent guidelines from leading nephrology organizations advocate for integrating exercise training into CKD care, recommending at least 150 min of moderate-intensity exercise per week. This narrative review examines clinical studies on exercise interventions in dialysis patients, highlighting their impact on health outcomes and quality of life. Additionally, it explores the physiological mechanisms underlying these benefits and assesses nephrologists’ perspectives on prescribing exercise training. By addressing these critical aspects, this review aims to underscore the necessity of incorporating exercise into CKD treatment strategies.

1. Introduction

Chronic diseases pose a significant challenge in today’s aging society, with physical inactivity—i.e., a sedentary lifestyle—being one of the major contributors to their onset [1]. Although the definition of physical inactivity is not always univocal, it is commonly defined as physical activity levels lower than those required for an optimal health status. Physical inactivity can lead to a loss of muscle strength, degenerative joint disease, and osteoporosis. It is also a well-known cause of atherosclerosis, cardiovascular diseases, and even cancer [2]. Additionally, being physically inactive increases the risk of neurological conditions such as Alzheimer’s disease, dementia, and depression. Among chronic diseases, chronic kidney disease (CKD) is a serious and increasingly prevalent condition affecting approximately 15% of the adult population in the United States and more than 500 million people worldwide. Regardless of its underlying causes, CKD carries a heavy disease burden, with an estimated 35.8 million disability-adjusted life years lost in 2017, and ranks among the top ten leading causes of mortality. Epidemiological studies consistently show a strong association between CKD and sedentary behavior, with more than 40% of CKD patients reporting no physical activity at all.

While growing evidence underscores the critical role of physical activity in the development and progression of CKD, the current medical approach remains primarily centered on pharmacological treatments. Lifestyle interventions, particularly exercise, often receive inadequate attention despite their potential to significantly improve patient outcomes [3]. One reason for the resistance to prescribing exercise training for CKD patients may, in part, stem from uncertainty regarding the most suitable types of exercise. In fact, ongoing debates persist over which forms of physical exercise are best suited for this high-risk group.

In the general population, physical activity and physical functioning are usually assessed by using valid instruments, such as pedometers, accelerometers, or even specific questionnaires. The direct assessment of physical activity allows us to directly measure body movements and the frequency and/or intensity of activities almost without influencing the subject. Generally speaking, dialysis patients show a lower measured physical performance when compared with reference values of the same age and sex, a condition generally worsening on non-dialysis days [4].

Recently, this critical issue has been addressed by specific guidelines, and several prominent scientific organizations—including the Renal Association, the American National Kidney Foundation, the Global Renal Exercise Network, and KDIGO—have converged on shared goals regarding the implementation of exercise training policies for individuals with kidney disease or on dialysis. These organizations advocate for exercise to enhance functional performance and improve the quality of life in this population. Specifically, the most widely recognized guidelines recommend that patients with chronic kidney disease engage in moderate-intensity exercise training for a total of at least 150 min per week or as tolerated, based on their cardiovascular and physical capacity [5].

The main aim of this scoping review is to evaluate clinical studies and trials that demonstrate how integrating physical exercise into the management of dialysis patients can lead to significant improvements in overall health and quality of life. We will also briefly discuss the pathophysiological mechanisms on the basis of the benefits of physical exercise for dialysis patients. Finally, and most importantly, we will critically explore nephrologists’ attitudes toward prescribing physical activity for dialysis patients.

The review will follow this scheme: (1) clinical trials based on exercise programs using different modalities during dialysis sessions or at home; (2) evidence supporting the beneficial effects of physical exercise on functional outcomes in dialysis patients; (3) notes on pathophysiological mechanisms; (4) nephrologists’ attitudes toward prescribing exercise training for dialysis patients.

2. Clinical Trials Based on Exercise Programs Using Different Modalities During Dialysis Sessions or at Home

To date, physical exercise interventions for dialysis patients have predominantly been implemented under supervision, either during dialysis sessions or in the intervals between sessions.

In a cross-over study, involving only 12 HD patients, the safety of intra-dialytic exercise versus intra-dialytic cardiovascular hemodynamics was tested. The intervention, consisting in intra-dialytic cycling, was performed for 30 min during the first or third hour of treatment, and was found not to worsen hemodynamic instability during dialysis, independent of the hydration status of participants [6]. The randomized controlled IHOPE trial, enrolling 138 HD patients in five clinics in Illinois, showed no effect of oral protein supplementation with or without intra-dialytic cycling training (duration: 45 min) on physical function [7]. In a randomized feasibility trial, both conventional and virtual reality-based intra-dialytic exercise were found to positively affect physical function. In this case, the intervention lasted sixteen weeks + four additional weeks, with 81 HD patients involved [8]. Another small randomized controlled trial (RCT), including 64 HD patients, compared patients participating in a 12-week intra-dialytic exercise program (n = 32) with a control group (n = 32) maintaining their habitual lifestyle. Even though no differences between the dialytic parameters and the baseline were found, the active arm showed an increase in health-related quality of life and a reduction in depression status [9]. An improvement in physical function and activity levels was also found in an RCT including 71 HD patients who were followed up with for 16 weeks. In this case, an intra-dialytic exercise program led by the nursing staff was compared to a home-based program, supervised by physical therapists employed by the hospital. The results of this trial showed that both the interventions were able to improve the physical function, activity levels, and health-related quality of life in the HD patients [10]. A small RCT including 26 HD patients showed that isometric exercises, associated with partial limb blood flow restriction before arteriovenous fistula, were effective in improving muscle strength and forearm circumference between the baseline and the end of the program. However, no differences were found between the exercise group and the control group [11]. Finally, a larger trial enrolling 101 HD patients, randomly assigned to intra-dialytic exercise (n = 51) or usual care (n = 50), found statistically significant improvements in the Short Physical Performance Battery score of the first group after a 6-month follow-up. No differences were found in lower extremity muscle strength or in 10 m walking speed between the two groups [12].

Intra-dialysis training is, by definition, limited to hemodialysis patients; thus, clinical trials specifically designed to test the benefits of exercise in peritoneal (PD) dialysis patients are scarce. In these patients, two small trials, whose results were published in 2019 and 2020, implemented unsupervised walking thrice weekly [13], or in-center exercise training led by one exercise physiologist during monthly appointments [14], both during a 12-week period. Overall, these trials reported improvements in both physical endurance, measured by walking distance or timed up-and-go tests, and the domains of quality of life and appetite.

Besides not being applicable in PD patients, physical exercise during dialysis sessions poses logistical and financial challenges—such as the need for specialized equipment, trained personnel, and more frequent patient visits to dialysis centers—thus, the feasibility and acceptability of these programs are reduced, and their broader adoption in clinical practice is limited. For this reason, the search for an exercise modality with good adherence that can be performed outside dialysis sessions has become a crucial issue, remaining a challenging priority for both stakeholders and clinicians.

In a trial by Fitts et al., 18 pre-dialysis and 18 dialysis patients were randomized to either exercise coaching and rehabilitation counseling or usual care. This small study showed that quality of life was stable or improved in patients in the active group, but declined in the control group; overall, pre-dialysis patients benefited more from the intervention than dialysis patients [15]. Similarly, The Life Readiness Program, a physical lifestyle rehabilitation program, was found to be effective in improving functional outcomes and health-related quality of life in a trial enrolling 82 patients (intervention n = 39; standard clinical management alone n = 43) [16]. A slightly larger trial, enrolling 100 HD patients, compared aerobic exercise, progressive muscle relaxation, and standard care in terms of their impacts on anxiety, sleep quality, and fatigue. Both interventions were started at the dialysis unit, and then performed at home for the entire follow-up period. The results showed that progressive muscle relaxation had a better effect on all the considered outcomes [17].

The lack of trials evaluating home-based physical exercise programs for dialysis patients was originally addressed by a pilot study, which adapted a model originally developed for peripheral arterial disease rehabilitation to the dialysis population [18]. This exercise regimen, designed to be simple and practical, could demonstrate both feasibility and potential benefits if implemented in this population.

After being further refined into an individualized, low-intensity, home-based regimen, it was implemented in the EXerCise Introduction To Enhance performance in dialysis patients (EXCITE) trial. This trial, a multicenter, randomized clinical trial, enrolled patients from nine dialysis centers across Italy and it is still the largest of its kind in terms of the number of patients enrolled [19].

In this trial, 296 dialysis (HD and PD) patients were randomized into groups receiving home-based walking exercise (n = 151) or usual care (n = 145) [19]. The six-month intention-to-treat analysis showed a notable improvement in the 6 min walking distance (6MWD), a measure of functional capacity, in the exercise group as compared to the control group. In addition, the trial showed also an increase in lower limb strength, measured by the 5 sit-to-stand test, in the exercise group but not in the control group. The treatment was also effective in improving two domains of quality of life, namely cognitive function and quality of social interaction. This is of paramount importance as it has been suggested that, as seen in other populations [20,21,22], exercise training may impact the cognitive performance of dialysis patients, paving the way for interdisciplinary approaches that integrate medical management, lifestyle modifications, and cognitive training to improve outcomes and quality of life in these patients.

The EXCITE trial demonstrated not only a positive effect of home exercise on physical performance in dialysis patients, but also potential benefits regarding mortality and hospitalization. In a per protocol analysis including patients who adhered to the assigned program, in the intervention group a significant and notable reduction in the number of hospitalizations was shown as compared to the controls, further highlighting the importance of compliance with exercise prescriptions in achieving meaningful health benefits. Of note, the EXCITE trial, applied via home-based intervention in both HD and PD patients, did not result in any particular differences, suggesting that each training method, as long as it is feasible, can benefit dialysis patients independently of the dialysis regimen.

The main results of the trial were confirmed in the group of patients aged > 65 years, a demographic that represents a growing proportion of the patient population [23], whereas a post-trial study showed a legacy effect of the intervention on the gain in walking distance achieved in the exercise group, an effect maintained at the 18th month and at the 36th month [24].

Similar results to those of the EXCITE trial were obtained by the DiaTT (Dialysis Training Therapy) trial, a multicenter, interventional, cluster-randomized controlled study including 1211 German HD patients from 24 dialysis centers [25]. In this trial, the effects of intra-dialytic, three-times-per-week, 60 min sessions involving supervised endurance and resistance exercise training were compared with the effects of standard care. At 12 months, 60 s sit-to-stand test (STS60) (Figure 1) repetitions improved in the exercise group but declined in the usual care group (p < 0.0001). The trial also showed a significant difference between the groups in the 6MWT (Figure 1), which was very close to the difference observed in the EXCITE trial (37.5 m vs. 39 m). Although non-significant, a positive trend in the physical summary score and vitality subscale of the SF-36 was observed in the exercise group, as well as a reduction in the median days spent in the hospital (two per year vs. five per year).

3. Evidence Supporting the Beneficial Effects of Physical Exercise on Functional Outcomes in Dialysis Patients

Evidence supporting the beneficial effects of physical exercise in dialysis patients has been increasing over the years. A list of trial on the topic of exercise training in patients with CKD and end end-stage renal disease is reported in

Table 1. Trials on the topic of exercise training in patients with CKD and end-stage renal disease.

Authors	Title	Year of Publication	Ref.
Anding-Rost et al.	Exercise during Hemodialysis in Patients with Chronic Kidney Failure	2023	[25]
Perez-Dominguez et al.	Effects of exercise programs on physical function and activity levels in patients undergoing hemodialysis: a randomized controlled trial	2021	[10]
Yabe et al.	Effects of intradialytic exercise for advanced-age patients undergoing hemodialysis: A randomized controlled trial	2021	[12]
Silva et al.	Effect of an exercise program with blood flow restriction on the muscular strength of patients with chronic kidney disease: A randomized clinical trial	2021	[11]
Lin et al.	Effects of Intradialytic Exercise on Dialytic Parameters, Health-Related Quality of Life, and Depression Status in Hemodialysis Patients: A Randomized Controlled Trial	2021	[9]
Bennett et al.	An Exercise Program for Peritoneal Dialysis Patients in the United States: A Feasibility Study	2020	[14]
Jeong et al.	Results from the randomized controlled IHOPE trial suggest no effects of oral protein supplementation and exercise training on physical function in hemodialysis patients	2019	[7]
Uchiyama et al.	Home-based Aerobic Exercise and Resistance Training in Peritoneal Dialysis Patients: A Randomized Controlled Trial	2019	[13]
Jeong et al.	Effects of acute intradialytic exercise on cardiovascular responses in hemodialysis patients	2018	[6]
Segura-Ortí et al.	Virtual reality exercise intradialysis to improve physical function: A feasibility randomized trial	2018	[8]
Manfredini et al.	Exercise in Patients on Dialysis: A Multicenter, Randomized Clinical Trial	2017	[19]
Amini et al.	Effect of Progressive Muscle Relaxation and Aerobic Exercise on Anxiety, Sleep Quality, and Fatigue in Patients with Chronic Renal Failure Undergoing Hemodialysis	2016	[17]
Manfredini et al.	The role of deconditioning in the end-stage renal disease myopathy: Physical exercise improves altered resting muscle oxygen consumption	2015	[18]
Tawney et al.	The life readiness program: a physical rehabilitation program for patients on hemodialysis	2000	[16]
Fitts et al.	Exercise coaching and rehabilitation counseling improve quality of life for pre-dialysis and dialysis patients	1999	[15]

. In 2015, Barcellos et al. included fifty-nine studies, randomizing 2858 participants, in a review focused on the effects of exercise in the whole spectrum of chronic kidney disease [26]. Many of the included studies were performed on dialysis patients, but the overall sample size was small (<50 in 67% of studies) and the follow-up period was short (from 8 to 24 weeks). Most studies used intra-dialytic exercise two to three times a week; forty-four studies tested aerobic exercises, lasting from 30 to 90 min per session, with intensities ranging from 60 to 80% of maximal oxygen consumption (VO₂ max); resistance exercises were used in nine studies. Despite these limitations, this review showed the positive effects of aerobic exercise on physical fitness [i.e., oxygen peak consumption (VO₂ peak) and heart rate variability (HRV)], muscular strength, and quality of life in dialysis patients.

In a meta-analysis by Clarkson et al. [27], including 27 randomized clinical trials involving dialysis patients, regular exercise was able to improve physical performance, as measured by 6 min walk distance (6MWD) tests, sit-to-stand time or repetitions, grip strength, step and stair climb times or repetitions, dynamic mobility, and short physical performance battery scores). The effect was independent of exercise modality (cycling on a stationary cycle ergometer, using a treadmill, ground walking, or weightlifting) and study setting (center-based intra-dialysis or off-dialysis, or home-based). Exercise training was also shown to improve cardiovascular structure and function, measured by reductions in left ventricular mass and arterial stiffness, as described in the CYCLE trial, a randomized controlled trial with the aim of examining the efficacy of 6-month intra-dialytic cycling on cardiovascular and physical function [28]. However, in all the above-mentioned trials, the duration of the exercise intervention was brief, lasting for 15 weeks on average (range 8–26 weeks), including the follow-up.

A meta-analysis of intra-dialytic exercise programs found clinically meaningful improvements in pulse wave velocity, a measure of arterial stiffness, as well as several cardiovascular health markers, including diastolic blood pressure, left ventricular ejection fraction, and heart rate variability. However, despite these improvements, the impact of intra-dialytic exercise on major adverse cardiovascular events and mortality remains poorly studied and uncertain [29]. Importantly, interventions targeting modifiable risk factors, such as glycemic control, blood pressure management, and physical exercise, have demonstrated potential in preserving cognitive function in individuals with chronic diseases.

The results of both the EXCITE and DiaTT trials coincide with the main findings of a recent network meta-analysis, including 78 studies with more than 3000 patients, comparing the efficacy of intra-dialytic versus home-based exercise [30]. This analysis demonstrates that combined training, whether performed during hemodialysis (20 trials) or at home (19 trials), was the most effective intervention for increasing VO₂ peak and reducing diastolic blood pressure when compared to usual care. Inspiratory muscle training resulted in the greatest improvement in 6MWT distance; however, this outcome was considered in only three studies with a limited number of participants. Both resistance and aerobic training were effective in reducing C-reactive protein levels, which decreased following resistance training. Aerobic training also improved Kt/V, while resistance training enhanced SF-36 physical functioning scores. All intra-dialytic exercise modalities provided benefits for measurable outcomes that were comparable to their respective home-based counterparts. Interventions lasting more than 12 weeks were more effective in improving functional capacity than shorter ones. Additionally, moderate- or moderate-to-vigorous-intensity training was beneficial, whereas mild-to-moderate- or mild-intensity training was not. The authors conclude that, overall, both intra-dialytic and home-based training effectively improved selected outcomes in hemodialysis patients, with no clear evidence favoring one approach over the other.

A recent systematic review by Battaglia et al. [31], which focused on home-based exercise interventions for patients undergoing hemodialysis (N = 691) or peritoneal dialysis (n = 100), reported significant improvements in walking speed during the 6MWT and in aerobic capacity, as measured by VO₂ peak. Additionally, these interventions were associated with enhanced quality of life, as reflected in the SF-36 scores.

To our knowledge, evidence specifically supporting the beneficial effects of exercise training in peritoneal dialysis patients is still scarce. Overall, there is a tendency for physical exercise to exhibit beneficial effects on QoL, VO₂, and blood pressure [32], but further trials are needed to confirm these results.

Taken together, this evidence suggests that in dialysis patients exercise interventions improve functional outcomes and quality of life independently of the chosen modality. Thus, the choice of the best exercise regimen should be based on the pros and cons inherent in different typologies. Exercise performed during dialysis allows for structured, supervised activities, providing a safe environment with real-time feedback from medical staff. This organized setting can greatly support patient adherence, integrating exercise into the routine treatment schedule. On the other hand, exercising at home is more convenient and adaptable. Patients can engage in activities such as walking, stretching, or using resistance bands within their daily routine. This autonomy enables individuals to exercise at their preferred pace and comfort level, encouraging self-reliance and consistent engagement. Maintaining an active lifestyle at home supports long-term continuity in physical activity, which is vital for sustained health improvements.

A combination of intra-dialytic and home-based exercise may be a possible compromise to maximize the benefits and reduce the disadvantages of the two methods. By blending these modalities, healthcare professionals can develop a well-rounded and personalized exercise strategy that improves compliance, supports patient autonomy, and maximizes the physical and psychological benefits for those undergoing dialysis.

Although current evidence has not identified any safety concerns and has demonstrated the beneficial effects of physical exercise programs on physical performance, further long-term studies are needed. These trials should evaluate the safety, adherence, long-term feasibility, and impact of both intra-dialytic and home-based exercise programs on quality of life, major clinical outcomes, mortality, and the risk of cardiovascular events in dialysis patients.

4. Notes on Pathophysiological Mechanisms

Exercise training is known to induce adaptive responses able to mitigate the pathophysiological complications of CKD. These adaptations are particularly significant in addressing cardiovascular dysfunction, chronic inflammation, and musculoskeletal deterioration, which are hallmarks of morbidity in this population.

In dialysis patients, the bioavailability of nitric oxide (NO), the most powerful endogenous vasodilating agent, is reduced because of oxidative stress and uremic toxins, and this impairs vasodilation and promotes arterial stiffness [33]. Exercise training has a positive impact on the pathophysiological processes leading to endothelial dysfunction due to its ability to enhance endothelial NO production through increased shear stress, reducing vascular resistance and improving arterial compliance. This compensatory mechanism prevents blood pressure dysregulation, a key contributor to cardiovascular morbidity [34]. In addition, regular physical activity promotes vascular remodeling, reduces intimal thickening, and enhances elastin integrity, thus lowering pulse wave velocity and reducing left ventricular afterload [35].

The combination of volume overload, hypertension, and vascular resistance contributes to Left Ventricular Hypertrophy (LVH) [36], a comorbidity affecting more than 80% of dialysis patients and associated with an increased risk of cardiovascular mortality [37]. Exercise reduces preload and afterload pressures, thereby alleviating myocardial strain. It also enhances myocardial perfusion, improving the oxygenation of cardiac tissues and mitigating ischemic risk [38].

Chronic inflammation is a systemic feature of CKD, exacerbated by uremic toxins, oxidative stress, and dialysis-related factors [39]. Exercise training exerts anti-inflammatory effects, which are critical for reducing the burden of inflammation-related complications.

For example, exercise increases the expression of IL-6, a pro-inflammatory cytokine also known for its anti-inflammatory effects, and enhances the release of anti-inflammatory mediators such as interleukin-10 (IL-10) and interleukin-1 receptor antagonist. This shift in the inflammatory milieu reduces systemic damage and supports tissue repair [40]. Another beneficial effect of exercise training is its ability to enhance the expression of antioxidant enzymes, reducing the accumulation of the reactive oxygen species (ROS) responsible for cellular damage in CKD. Thus, by mitigating oxidative stress, exercise not only reduces inflammation, but also preserves endothelial and muscular integrity [40].

In advanced CKD, and particularly in dialysis patients, systemic inflammation and impaired insulin signaling potentiate the catabolic pathways at the expense of the anabolic ones, leading to muscle protein degradation [41]. Resistance training stimulates anabolic pathways by activating the mechanistic target of rapamycin (mTOR), enhancing muscle protein synthesis, and reducing proteolysis, thus counteracting uremic myopathy and promoting hypertrophy [42].

Renal osteodystrophy, characterized by impaired bone turnover and mineralization, increases fracture risk in dialysis patients [43]. Weight-bearing exercises promote osteoblast activity and mechanical, loading-induced bone remodeling, supporting skeletal strength and reducing fracture incidence [44]. Moreover, exercise training increases capillary density in skeletal muscles, improving oxygen and nutrient delivery while reducing lactate accumulation [45]. This enhances endurance and reduces the risk of fatigue-related immobility, thereby maintaining functional independence [46].

From a pathophysiological perspective, physical activity addresses the intricate complications of dialysis by promoting adaptive changes in the cardiovascular system, reducing chronic inflammation, and restoring musculoskeletal function. These mechanisms are integral to mitigating the systemic burden of comorbidities in CKD and dialysis. With all these considerations in mind, tailored exercise regimens, designed in agreement with patients’ preferences and with the resources available in dialysis units, should be considered an essential component of therapeutic strategies and, thus, are proposed to improve outcomes in clinical practice and enhance the quality of life in this vulnerable population. The question still lingering in the scientific community is the modality of exercise training that should be prescribed and ultimately delivered.

5. Nephrologists’ Attitudes Toward Prescribing Exercise Training for Dialysis Patients

Current international guidelines strongly recommend that clinicians prescribe physical exercise to a wide range of patient populations, including individuals with oncological conditions and heart failure. Furthermore, specific guidelines have been developed for patients with CKD. Despite these recommendations, the prescription of exercise training to CKD patients remains uncommon, and this critical aspect of patient care is frequently neglected. In other words, inertia in prescribing physical exercise is a prevalent issue among nephrologists in their daily clinical practice. Analyzing the reasons behind this behavior is crucial before trying to implement exercise programs in daily routine.

A critical issue that warrants attention is the significant barriers dialysis patients face when engaging in exercise training [47]. According to the authors, fatigue on dialysis and non-dialysis days, lack of motivation, and shortness of breath are the most reported barriers. More recently, Battaglia and colleagues [48] developed a 14-item electronic survey comprising multiple-choice questions that address various topics, including exercise training programs, physical assessments, barriers preventing exercise participation and implementation, counselling practices for exercise and physical activity, perceived benefits of exercise, existing evidence in the literature, and research priorities. Additionally, data on the characteristics of the participating centers were collected. The survey was conducted nationwide in Italy, and 93% of the respondents were aware of the scientific evidence supporting the benefits of regular exercise programs for patients with CKD. Moreover, 75% of the respondents believed that nephrologists should be responsible for providing physical activity counselling. However, only 26% of the centers offered exercise programs primarily for dialysis patients, and 63% rarely or never assessed physical activity as part of patient management. In total, 99% of the respondents identified barriers to implementing exercise programs, including a lack of funding, institutional disinterest, patient refusal, and negative attitudes from healthcare staff. A total of 46 research priorities concerning exercise in CKD patients were proposed, most of them focusing on the effects of exercise and physical activity on cardiovascular, nutritional, and psychosocial outcomes.

These findings suggest that, while nephrologists acknowledge the importance of exercise, there may be practical barriers or a lack of infrastructure to integrate exercise into routine care.

The fact that 75% of the surveyed nephrologists believe they should be responsible for exercise and physical activity counseling indicates recognition of their key role in patient management. However, the barriers identified by 89% of the respondents—such as funding issues, a lack of institutional support, patient reluctance, and negative attitudes among healthcare personnel—highlight significant challenges in implementing exercise programs effectively. This survey, while highlighting the limited availability of exercise programs and physical activity evaluation in clinical practice, discloses a remarkably high level of interest towards recommending physical activity and prescribing aerobic exercise programs for CKD patients, along with many logistic barriers [48].

These findings underscore the critical importance of addressing barriers to physical activity in dialysis patients and promoting exercise as an integral component of their care.

A new approach that is potentially useful in reducing barriers preventing the application of physical training programs has recently been proposed [49]. This approach is mainly based on the identification of patient-specific barriers and obstacles stemming from healthcare staff; based on this information, it is possible to develop a targeted strategy to overcome these challenges.

To evaluate patient-related barriers, the questionnaire developed by Delgado & Johansen [47] can be a valuable resource. This tool explores multiple types of patient-specific and disease-related hindrances to physical activity, including psychological, physical, financial, and time-related factors, as well as the presence of comorbidities. In addition, brief, validated screening tools for detecting symptoms such as depressive mood, recent falls, or functional limitations are readily accessible and can be seamlessly integrated into standard clinical workflows.

The perspectives and practices of healthcare providers regarding physical activity counseling can be assessed using the Fiaccadori questionnaire [50], which is a revised version of Johansen’s original instrument. It contains 17 items, with 13 questions specifically tailored to nurses, focusing on their views and involvement in promoting physical activity among dialysis patients.

While nephrologists typically acknowledge the importance of increasing activity levels, they rarely provide direct encouragement [30]. This hesitation often stems from both time constraints and a lack of training in effective counseling techniques [51,52]. To bolster physician confidence in this area, clinical guidelines should clearly outline recommended counseling strategies [53]. Additionally, better utilization of existing resources—such as exercise programs tailored for dialysis patients—could support nephrologists in prescribing suitable physical activities.

6. Conclusions and Perspectives

In the current medical era, the management of chronic diseases remains largely dominated by a pharmacological approach, with insufficient emphasis placed on lifestyle interventions. Exercise training has been shown to provide numerous benefits, including reductions in inflammation, improvements in body weight and fasting glucose levels, enhanced functional capacity, better quality of life, and positive effects on major clinical outcomes such as hospitalization rates and cardiovascular events in patients with kidney disease.

Given the organizational and financial challenges associated with intra-dialytic exercise modalities, there is a pressing need to gradually incorporate home-based exercise into the training programs of dialysis centers to enhance patient adherence and the practicality of these interventions. While home-based training shows promise, the existing literature on its effectiveness in managing health-related outcomes for dialysis patients is still not fully established. To date, only a limited number of RCTs have specifically targeted walking exercise programs and used walking capacity as the primary outcome measure. Home-based exercise programs for dialysis patients are still scanty, with the EXCITE trial still being the only one with a consistent number of dialysis patients enrolled. Nevertheless, the potential of physical exercise in managing dialysis patients—a particularly high-risk population—deserves greater recognition. In addition, in spite of the growing interest in the effects of medicine on different genders, the different impacts of exercise training on mortality in males and females have scarcely been explored. Recently, a paper based on the NANHES cohort showed that, differently from male CKD participants, in whom any amount of physical activity reduced all-cause mortality, only extreme training was effective in females patients [54]. Therefore, new studies are also needed to explore the specific impact of exercise training on female dialysis patients, who may face unique challenges and responses to exercise interventions.

Although narrative, this review has some limitations. First, due to the scarcity of studies performed on PD patients, our work mainly focuses on the effects of exercise training in HD patients, thus inherently limiting the scope of the review. Secondly, the cited studies exhibit heterogeneity in their design (RCTs, cross-over studies, feasibility trials), sample sizes (ranging from very small to relatively large), follow-up durations (mostly short-term), and outcome measures. This variability makes it challenging to synthesize the findings and draw robust conclusions about the overall impact of exercise.

In conclusion, there is a pressing need for comprehensive, long-term trials with large sample sizes to rigorously evaluate the safety, adherence, feasibility, and overall impact of physical exercise on quality of life and critical outcomes such as mortality in this vulnerable population. Future research should investigate factors that may influence individual responses to exercise, including patient characteristics (age, comorbidities, functional status, gender), dialysis modality, and personal preferences. This will pave the way for more tailored and effective exercise programs.