DISCUSSION
HED, adiposity, emotions and external stimulus‐orientated
RECRUITMENT, ADIPOSITY, CORTEX
The main findings from this study are that overall between‐trial differences in grey matter and regional CBF were apparent but the time‐course of CBF was not influenced directly by exercise in healthy young men. A single bout of running suppressed subjective appetite ratings and increased food cue reactivity in brain regions linked to attention, anticipation and encoding of reward, and episodic memory retrieval. However, the sensitivity of the exercise‐induced BOLD signal changes during a food cue reactivity task was not altered substantially after accounting for the underlying CBF.The main effect of trial analysis revealed that CBF was higher in grey matter, the posterior insula and in the region of the amygdala/hippocampus, and lower in the medial OFC and dorsal striatum in the exercise versus control trial. This extends previous findings demonstrating pre‐to‐post exercise alterations in ASL derived CBF quantified globally and in regions linked to cognitive processing (MacIntosh et al., Despite identifying overall between‐trial differences in CBF, we did not detect any temporal patterns in grey matter or regional CBF when tracked ~8–28 min after exercise/rest supported by the absence of any trial‐by‐time interactions. This appears to contrast previous findings that have reported pre‐to‐post exercise changes in CBF when assessed at multiple time‐points after exercise. Specifically, greater hippocampus CBF has been reported 15‐, 40‐ and 60‐min after a moderate‐intensity exercise bout (Steventon et al., Analysis of the BOLD data identified greater exercise‐induced food cue reactivity in the medial frontal pole, whereas reactivity to HED versus non‐food cues was lower in the middle frontal gyrus after exercise. Although knowledge of the precise function of these frontal cortical regions in human behaviour is still evolving, the medial frontal pole appears to hold distinct functions in self‐monitoring of emotions and external stimulus‐orientated thought (Bludau et al., The CBF‐adjusted primary model identified greater food cue reactivity in the paracingulate gyrus and posterior cingulate gyrus, located on the superior aspect and in the caudal region of the cingulate cortex, respectively, in addition to the precuneous cortex located adjacent to the posterior cingulate gyrus. Previous work has reported lower food cue reactivity in the posterior cingulate and cingulate gyrus after exercise (Crabtree et al., Alongside the elevated hippocampus CBF in the exercise trial, exercise evoked greater food cue responsiveness in this region of the temporal lobe which persisted after adjustment for CBF. This supports previous findings in children (Masterson et al., Our BOLD analysis also revealed lower reactivity to HED versus LED and greater reactivity to LED versus HED food images in response to exercise in the precentral gyrus. This region is primarily involved in motor responses but appears sensitive to food cue exposure (Huerta et al., Previous literature has demonstrated consistent but transient suppressions of appetite during and immediately after acute exercise bouts (Dorling et al., Key strengths of this study include the acquisition of adjacent pCASL and BOLD data and the food cue stimuli comprised distinct low and high hedonic value categories of known energy density which were confirmed to activate reward‐related brain regions. Furthermore, the pre‐intervention fMRI scan and the rest control trial allowed variability at baseline and without an exercise stimulus, respectively, to be captured appropriately in the analysis. A notable limitation is the recruitment of a small sample of healthy, lean young men and, therefore, future extension of this work to larger, more diverse and clinical populations is encouraged including women and in individuals with excess adiposity who typically display heightened food cue reactivity (Meng et al., 