Chronic kidney disease (CKD) consists of kidney damage, with a consequent progressive and irreversible loss of kidney function. In the early stages of the disease, there is already a reduction in circulating levels of α-klotho protein, which is related to worsening renal function. Therapeutic strategies that increase serum α-klotho levels can be of great value in the treatment of CKD. Electrical stimulation contributes to the reduction of reactive oxygen species, DNA damage and improves the efficiency rate of dialysis, suggesting a systemic effect in patients with end-stage CKD. The aim of this study is to evaluate the effects of bioelectric stimulation on renal function and physical capacity in patients with CKD. For this, patients will be randomized into bioelectric stimulation or a control group. Bioelectric stimulation will be performed three times a week for eight weeks. The control group will only be evaluated and re-evaluated. The following pre-and post-intervention assessments will be performed: analysis of the plasma content of α-Klotho and soluble creatinine to assess renal function, six-minute walk test to assess functional capacity; dosage of interleukins and tumor necrosis factor to analyze the inflammatory profile; sit and stand test with 10 repetitions and load cell dynamometry to assess lower limb muscle strength and application of the EuroQoL-5D questionnaire for quality of life. Biochemical analyzes for renal function and inflammatory profile will also be performed after four weeks of follow-up.

Inclusion Criteria:

• Age 18-80 years of age;
• CKD with glomerular filtration rate (GFR) between 15-59 ml/min (III and IV stage of CKD) for more than 3 months;
• To be able to ambulate > 300 meters in 6 minutes walk test.

Exclusion Criteria:

• Cognitive dysfunction that prevents the performance of evaluations, as well as an inability to understand and sign the informed consent form;
• Intolerance to the electrostimulator and/or alteration of skin sensitivity;
• Skin lesions/burns at the electrode placement site;
• Patients with stroke in past 6 months with residual limitation to ambulation;
• Disabling musculoskeletal disease;
• Uncontrolled hypertension (systolic blood pressure > 230 mmHg and diastolic blood pressure > 120 mmHg);
• Grade III or IV heart failure (NYHA);
• Patient with a pacemaker;
• Uncontrolled diabetes (fasting blood glucose > 250 mg/dL);
• Unstable angina;
• Coronary stent placement in past 3 months;
• Recent acute myocardial infarction (two months);
• Fever and/or infectious disease;
• Peripheral vascular disease in the lower limbs that limits ambulation or deep vein thrombosis;
• Chronic obstructive lung disease that limits ambulation or need for oxygen therapy;
• Obesity (Body Mass Index≥35);
• Patient with active cancer.