Volume 2, Issue 6, Pages 334-344 (December 2001) The effect of maximal exercise on temporal summation of second pain (windup) in patients with fibromyalgia syndrome  Charles J. Vierck, Roland Staud, Donald D. Price, Richard L. Cannon, Andre P. Mauderli, A.Daniel Martin  The Journal of Pain  Volume 2, Issue 6, Pages 334-344 (December 2001) DOI: 10.1054/jpai.2001.25533 Copyright © 2001 American Pain Society Terms and Conditions

Fig. 1 Temporal summation of late thermal sensations is shown for baseline series not preceded by exercise (open diamonds) and after 15 minutes of mild exercise (closed squares) or exercise to exhaustion (closed circles). Ratings for left- and right-hand stimulation are averaged for each condition across subjects. Data from testing sessions that began 1.5 minutes (A) or 10 minutes (B) after completion of exercise are compared separately with the control condition of no exercise. All testing sessions began with a series of 20 thermal stimuli, followed by a 30-second interval and then a series of 40 stimuli to the thenar eminence of the hand. The horizontal dotted line identifies the threshold level for pain (a rating of 20). Exercise reliably decreased the temporal summation of late pain sensation intensities for pain-free subjects. The Journal of Pain 2001 2, 334-344DOI: (10.1054/jpai.2001.25533) Copyright © 2001 American Pain Society Terms and Conditions

Fig. 2 Baseline sensitivity to repetitive thermal stimulation for pain-free subjects and subjects with FMS in sessions not preceded by exercise. (A) Verbal ratings of the magnitude of thermal sensations elicited by the initial stimulus in series presented at ISIs of 2 to 5 seconds. These ratings did not differ significantly between groups. (B) Ratings of the maximal sensation intensities produced by series of stimuli at ISIs of 2 to 5 seconds. These ratings were significantly higher across ISIs for subjects with FMS. (C) Percent increase in sensory magnitude from the first to the last stimulus (or maximal sensation) in series of stimuli at ISIs of 2 to 5 seconds. These values were derived from averaged data in (A) and (B) and were not tested statistically. (D) Magnitude of aftersensations produced 15 and 120 seconds after the last series of stimuli in baseline sessions. Comparisons at each time period revealed significant differences between groups. The Journal of Pain 2001 2, 334-344DOI: (10.1054/jpai.2001.25533) Copyright © 2001 American Pain Society Terms and Conditions

Fig. 3 Ratings of late sensation magnitude in baseline testing sessions and 10 minutes after strenuous exercise, averaged across all series presented to control subjects (left panel) and subjects with FMS (right panel). Average ratings are shown for the initial stimulus in each series, the maximal sensation magnitude during series of contacts (Max), and aftersensations at 15 seconds (AEff1) and 120 seconds (AEff2) after completion of the last series. Statistical tests revealing significant differences in exercise effects for control subjects and subjects with FMS used data from series presented at each ISI (not shown) and included all measures. The Journal of Pain 2001 2, 334-344DOI: (10.1054/jpai.2001.25533) Copyright © 2001 American Pain Society Terms and Conditions

Fig. 4 VAS ratings of clinical pain before exercise, 10 minutes after exercise, and 24 hours after exercise by 10 subjects with FMS. The Journal of Pain 2001 2, 334-344DOI: (10.1054/jpai.2001.25533) Copyright © 2001 American Pain Society Terms and Conditions

Fig. 5 Mean daily VAS ratings of pain intensity and unpleasantness during 8 days after maximal exercise by 7 subjects with FMS. Only pain intensity ratings were obtained before exercise (Pre.). The Journal of Pain 2001 2, 334-344DOI: (10.1054/jpai.2001.25533) Copyright © 2001 American Pain Society Terms and Conditions