Introduction: The use of neuromuscular electrical stimulation (NMES) in athlete training has become an increasingly common feature among competition teams. Among the main benefits of NMES are the increase in muscular strength and improvement in athletes' performance. Surveys demonstrate the benefits of basketball, volleyball, soccer, swimmers and Olympic lifters using NMES, but no studies have been conducted on runners. Objectives: To evaluate the effects of 6 weeks of training with NMES, on knee peak torque (PT), ventilatory anaerobic threshold, maximum oxygen consumption (VO2max) and running economy in recreational runners. Methods: Randomized clinical trial involving 30 long distance runners, being randomly distributed in 2 groups of 15 participants each. All individuals will perform isokinetic evaluation of the lower limbs and ergospirometry. After these evaluations, all athletes will perform the same running training (CT), in addition to the CT the intervention group will perform NMES on the knee extensors 3 times a week for 15 minutes.

Participants who meet the eligibility criteria will be invited to participate in the study and, after signing the informed consent form, will perform initial clinical evaluation and will be randomized into two groups, being: control group (CG) and intervention group (GI) - using the medium-frequency alternating current. Each group will consist of 15 subjects who will have as dependent variables, the evaluation of the following items: peak muscle torque, analysis of ventilatory anaerobic thresholds, running economy and maximal oxygen consumption.

The intervention with the NMES will be considered as an independent variable. All groups will have the dependent variables evaluated before and after the intervention, which will consist of 18 sessions (6 weeks). The NMES training will be performed 3 times a week and will never be applied for two consecutive days, as shown in the flowchart All individuals, being they of the CG or the GI will perform a running training (TC), between 15 and 40 km per week and will be guided how to perform them, and the GI patients will perform a muscle strengthening protocol with NMES, which will be carried out in a specific place and prepared for intervention, in addition to the TC.

Inclusion Criteria:

• Included will be male individuals, aged 30 to 45 years
• recreational funders, who have been performing the activity for at least 1 year.
• Totaling at least 15km and a maximum of 40km of training per week,
• Who do not use NMES for the purpose of muscle training.

Exclusion Criteria:

• Subjects who present muscle injuries and / or joint injuries in the lower limbs (LMI) in the last 6 months can't be part of the study.
• Who are unable to perform the isokinetic test
• Who are unable to do ergospirometric test,
• Who meet the contraindications criteria of NMES

Included will be male individuals, aged 30 to 45 years, recreational runners, who have been performing the activity for at least 1 year, totaling at least 15km and a maximum of 40km of training per week, who do not use NMES for the purpose of muscle training.

Subjects who suffer muscle injuries and / or joint injuries in the lower limbs (LMW) during the 6 weeks of training, Subjects who present muscle injuries and / or joint injuries in the lower limbs (LMI) in the last 6 months can't be part of the study.

Investigations of the peak muscle torque, analysis of ventilatory anaerobic thresholds, running economy and maximal oxygen consumption will be performed by a blind investigator. Data analysis will be performed by a blind investigator in the control and intervention groups.