Purpose: The cold pain sensitivity in fighter pilots was studied by using a cold pressor test.
Methods: The pilots were divided into two groups: one group consisting of eight pilots (N = 8) who had experienced several acute in-flight neck pain attacks, and the control group (N = 8) who had not experienced these pain conditions under similar work and environment conditions. In each pilot cold pain thresholds and pain and unpleasantness responses to suprathreshold cold stimulations were recorded during repeated tests. The ratings of pain and unpleasantness responses to cold stimulations were evaluated by visual analog scales (VAS). The effect of exercise on cold pain sensitivity was tested in a separate experiment. Exercise was performed on a cycle ergometer at different workload levels (50-200 W).
Results: In the control conditions (resting measures) of this study during repeated cold pressor tests, the average pain thresholds and pain or unpleasantness responses to suprathreshold cold stimulation were not different between groups. Physical exercise increased pain thresholds (P < 0.001) in pilots with a history of neck pain attacks but not in control group. Exercise induced a significant decrease in pain responses and unpleasantness responses to suprathreshold stimulation in both groups. This exercise effect was more marked both in pain intensity (P < 0.05) and unpleasantness responses (P < 0.01) in pilots with a history of neck pain attacks. Moreover, exercise more markedly (P < 0.05) decreased unpleasantness than pain intensity responses in both groups of pilots.
Conclusions: The results suggest that exercise stress-related analgesia mechanisms may be enhanced in pilots with a history of acute in-flight neck pain attacks. Moreover, sensory and nonsensory aspects of pain experience may be differentially influenced by exercise stress.