Despite the tremendous advances in dialysis technology, hemodialysis (HD) is a significant challenge for dialysis patients and quality of their lives[2]. Research has shown for years that dialysate fluid temperature and especially the typical dialysis (TD) temperature at (37°C) are complicated by hemodynamic instability which leading to an increased risk of heat-induced hypotension causing patient discomfort and increased mortality.

Cold dialysis (CD) is defined as the reduction of dialysis fluid temperature to 35-36°C, approximately 1°C below the typical dialysate temperature which ranges between 37-38°C. A number of studies have reported beneficial effects of CD on maintaining hemodynamic stability, minimizes hypotension and exerts a protective effect over major organs including the heart and brain. In addition, current evidence showed the protective effect of CD in cardiac performance during the dialysis session. As the investigators know until today cardiovascular mortality is an important issue for nephrologists that care for ESRD patients, however, many other benefits have been observed on patients' overall health and quality of life levels by used of CD.

The above-mentioned benefits of CD in the hemodynamic stability and the general quality of life of the patients are highlighted even further due to the ever-increasing adoption of intradialytic exercise programs. It has been well established that intradialytic exercise leads to benefits of physiological, functional, and psychological deterioration, which commonly accrues as a consequence of biological aging, catabolic illness, and a sedentary lifestyle, factors that may all contribute to the progressive decline of vitality and quality of life commonly observed in ESRD patients.

However, despite a strong rationale for the implementation of intradialytic exercise programs and the aforementioned benefits of CD, the separate and combined effects of these protocols in aspects related to quality of life and health in ESRD patients have not been investigated to date.

The aim of the current clinical study was to assess the effect of exercise rehabilitation regimes in combination with changes in dialysate temperature in aspects related to quality of life and health in end-stage renal disease patients receiving hemodialysis.

The primary aim of the clinical study was to investigate the combined effect of cold dialysis and aerobic exercise in aspects related to health. More specific:

1. To investigate the thermoregulatory responses of hemodialysis patients under four different hemodialysis protocols.
2. To assess the changes in muscular architecture and functional capacity in dialysis patients after 7 months of intradialytic exercise training.
3. To assess the impact on insulin sensitivity and glucose disposal.

Inclusion Criteria:

• Clinically stable ESRD patients receiving regular hemodialysis treatment for at least 3 months,
• adequate dialysis delivery Kt/V >1.1
• good compliance of dialysis treatment
• serum albumin >2.5 g/dL
• hemoglobin ≥11g/dL.

Exclusion Criteria:

• Patients with a reason to be in a catabolic state,
• hyperthyroidism,
• active vasculitis,
• malignancies,
• pregnancy
• HIV,
• opportunistic infections,
• musculoskeletal contraindication to exercise,
• requirement for systemic anticoagulation,
• participant or participated in an investigational drug or medical device study within 30 days,
• active inflammations, that required intravenous antibiotics within 3 months prior to enrollment,
• diabetics receiving insulin therapy,
• New York Heart Association grade IV heart failure,
• mental incapacity to consent.