Effects of Lumbar Transcutaneous Electrical Nerve Stimulation on Exercise Performance in Patients With Chronic Obstructive Pulmonary Disease

"4 self adhesive surface electrodes are positioned by pair at the L3-L4 level, laterally.~Stimulation is setted at rest, 10min before constant workload testing. During this period, intensity is increased every 3minutes to the maximum tolerated by the patient (pain threshold). Thereafter, intensity is not increased anymore during the test.~It is explained to the patient that he might or no experience the electrical stimulation sensation.~Current characteristics : 100Hertz, 100ms, bidirectional. Constant workload testing : 60-70rpm ; 75% Wpic ; up to exhaustion or rpm \< 60 during more than 10s."

"4 self adhesive surface electrodes are positioned by pair at the L3-L4 level, laterally.~Stimulation is setted at rest, 10min before constant workload testing. During this period, intensity is increased every 3minutes to the maximum tolerated by the patient (pain threshold). Thereafter, intensity is not increased anymore during the test.~It is explained to the patient that he might or no experience the electrical stimulation sensation.~Current characteristics : 4Hertz, 100ms, bidirectional. Constant workload testing : 60-70rpm ; 75% Wpic ; up to exhaustion or rpm \< 60 during more than 10s."

The procedure is the same as high-frequency transcutaneous electrical stimulation but intensity is progressively setted back to 1mA (over a 45sec period) after every increment so that constant workload testing is performed with 1mA.