Electromyographic (EMG) normalization method for cycle fatigue protocols.

PURPOSE To determine the most effective electromyographic (EMG) normalization method for cycling fatigue protocols. METHODS Ten healthy subjects performed two 5-s isometric knee extension maximal voluntary contractions (MVC) at a knee joint angle of 60 degrees, two fixed cycle pedal contraction at knee joint angles of 60 degrees (60 degrees A) and 108 degrees (108 degrees A), and a dynamic single maximal revolution of a cycle pedal (1REV). Integrated EMG (IEMG) data were recorded for all contractions and power output recorded during MVC and 1REV. RESULTS Mean IEMG for MVC was significantly (P < 0.01) greater than 60 degrees C, 108 degrees C, and 1REV. There were no significant differences between MVC and 1REV power output/EMG relationship. CONCLUSIONS MVC will record a higher IEMG than 60 degrees A, 108 degrees A, and 1REV. As IEMG was greatest during MVC, and the relationship between IEMG and power output was not different between MVC and 1REV, normalization against maximal possible recruitment potential is most likely during MVC.