Moderate-intensity muscle pain can be produced and sustained during cycle ergometry

The aim of this experiment was to determine whether moderate-intensity quadriceps muscle pain could be produced and sustained during cycle ergometry. 12 women volunteers completed a peak cycle ergometry test during which quadriceps muscle pain-intensity ratings were obtained using a 0-10 scale. On a subsequent day, participants cycled for 20 min beginning at the power output associated with quadriceps muscle pain threshold during the peak test. Participants manipulated power output during the first 10 s of each minute to produce and sustain moderate-intensity quadriceps muscle pain. During the last 20 s of each minute, VO2, ratings of quadriceps muscle pain intensity, and ratings of perceived exertion (Borg 6-20) were obtained. Moderate-intensity quadriceps pain ratings were achieved within 4 min, during which time the average power output was increased from 124 to 138 W. Pain-intensity ratings were unchanged from minutes 4 to 20 (F = 0.94; df = 16, 176; P = 0.52; eta2 = 0.079). Quadriceps RPE responses mimicked the pain responses. To sustain a moderate-intensity quadriceps pain participants reduced power output significantly (F = 7.75; df = 16, 176; P < 0.001; eta2 = 0.413) and in a linear fashion by 21.7 W (15.7%). The changes in % VO2peak were similar in pattern to the changes in power output but smaller in magnitude. 1) College women can produce and sustain a moderate-intensity quadriceps muscle pain during cycle ergometry, 2) moderate-intensity quadriceps muscle pain is sustained by reducing power output, and 3) sustaining moderate-intensity quadriceps muscle pain during short duration cycling is associated with a "hard" perceptual effort and 69-74% VO2peak.