Many different factors affect running performance, transcranial direct current stimulation (tDCS) is a widely used and available neuromodulation tool and could hypothetically facilitate the supraspinal drive and thereby act upstream of the motor cortex to prolong the muscles work in time to exhaustion trials. While it appears to decrease the rating of perceived exertion (RPE) during cycling, little is known about the effects of tDCS on physiological performance parameters such as maximal oxygen consumption (VO2max), maximal aerobic speed (MAS) and lactate thresholds in runners. The aim of this prospective randomized sham-controlled clinical trial is to investigate the physiological effects of tDCS applied over the motor cortex on perceived exertion and performance-related parameters measured by an incremental treadmill test to exhaustion. This research thus aims at answering the following questions: 1. Is active tDCS applied bilaterally over the motor cortex significantly more efficient than sham tDCS to improve the TTE? 2. Does active tDCS decreases the RPE, as compared to sham? 3. Is there any significant difference between active and sham tDCS on the physiological parameters measured during an incremental test to exhaustion, namely: VO2max, MAS, respiratory exchange ratio, blood lactate levels, maximal heart rate? 4. Does the baseline level of physical fitness influences response to tDCS? The investigators hypothesize that 1) performance as measured by time to exertion will be increased following active and not sham tDCS due to a decreased perceived rate of exertion without significantly altering the other physiological parameters; and 2) performance as measured by incremental treadmill test to exhaustion will be more improved in recreational as compared to trained runners.
Inclusion Criteria: * Healthy subject * Regular running activity above 2 hours/week * VO2max above 30 mL/min/kg Exclusion Criteria: * Pacemaker * Intracerebral metallic implant * Smoking * Using dietary supplementation or medication potentially affecting the CNS * Musculoskeletal injury within the past 6 weeks