Caution needed when interpreting muscle activity patterns during extremely low pedaling cadence

摘要

Dear editor,We noticed recent research that has just been published in Journal of Sport and Health Science(JSHS),comparing the muscular activity patterns in 1-and 2-legged cycling by Park and Caldwell.1 The authors reported that changes in muscle activities with 1-legged pedaling are due to a variety of changes in mechanical aspects of the pedaling motion,including altered crank torque patterns within the crank cycle,decreased pelvis stability,and the need for increased knee and ankle stiffness during the upstroke.The experiment was welldesigned and the discussion was fascinating.However,the testing protocol does not support the significance of the project,as stated in the first sentence of the abstract,“One-legged pedaling is of interest to elite cyclists and clinicians.”Their testing was conducted at 30 revolutions per min(rpm)and 30 watts(W),and both are too low for any kind of mechanical demand for cycling,either competitive sports or rehabilitation.The preferred cadences of experienced cyclists are approximately 85-95 rpm,whereas the most economic cadences are approximately 55-60 rpm.