INTRODUCTION
high‐intensity, pain
SECONDARY, SYNDROMES
Exercise has been identified as an effective intervention for managing patients with pain syndromes. Previous studies have demonstrated that global aerobic exercises (Vaegter et al., The analgesic effect following exercise in asymptomatic individuals tends to be correlated with exercise intensities (Baiamonte et al., The EIH effects following exercises of different intensities might be attributed to the mechanisms of endogenous pain modulation (Koltyn et al., Given that the threshold of descending facilitation is lower than that of inhibition (You et al., However, moderate‐ or low‐intensity stimuli may activate the cannabinoid (Crombie et al., Considering the potential modulation of EIH effects by exercises of different intensities, we aimed to compare the primary and secondary changes in PPT and PPTol in asymptomatic individuals following running exercises of various intensities. We also measured changes in CPM responses before and 24 h after the running sessions to preliminarily reveal the role of endogenous pain modulation in EIH effects.We hypothesized that (1) low‐, moderate‐, and high‐intensity running exercise might elicit EIH responses and increase the PPT and PPTol, (2) the analgesic effects of moderate‐ or low‐intensity exercise may persist at the 24‐h follow‐up, while high‐intensity exercise may decrease the pain threshold the next day, and (3) the CPM responses at 24 h following high‐intensity running might be attenuated compared with those following low‐ and moderate‐intensity running.