The sample size calculation was performed in order to advance in GPower 3.1 program based on the results obtained in the study conducted neuromuscular electrical stimulation during hemodialysis in patients with chronic kidney disease. the values of peripheral muscle strength were used before and after treatment respectively 185.4 ± 53 and 222.4 ± 36.6 and the values for the assessment of pre exercise capacity (401.3 ± 55) and post (428.9 ± 69.2) waiting for electrostimulation observe a similar effect. Using an error of 5% (80% test power), it was determined the need for inclusion of 12 patients for the variable peripheral muscle strength and 34 patients for exercise capacity. Recital 10% loss would require the evaluation and treatment of 14 and 38 patients to check the effect on peripheral muscle strength and on exercise capacity respectively.