Change in temporal summation in the lumbar innervated region following randomly assigned intervention. A significant group (intervention) × time (preintervention to postintervention) interaction was present for hypoalgesia to temporal summation in the lumbar innervated region (F2,33=3.41, P=.05, partial η2=0.17). Pair-wise comparison indicated significant hypoalgesia in the participants who received spinal manipulative therapy (SMT), which was not observed in the participants who rode a stationary bicycle or performed lumbar extension exercises. Positive numbers along the Y axis indicate hypoalgesia. Error bars represent one standard error of the mean. Asterisk indicates significant at P≤.05.
NRS = numeric rating scale, with anchors of 0 ("no pain at all") and 100 ("worst pain imaginable")