Exercise intervention modulates food reward in obesity: efficacy, mechanisms, and prospects

Aberrant food reward processing is a key contributor to the development and maintenance of obesity, and exercise intervention has been proposed as a feasible way to correct this maladaptive eating pattern. Nevertheless, inconsistent research findings mean its real efficacy and internal regulatory mechanisms remain controversial. This work adopted a systematic review design following standardized literature screening and bias evaluation procedures to sort out all qualified controlled trials focusing on exercise-induced changes in food reward among obese individuals, then synthesized existing evidence and conducted subgroup analyses to explore multiple potential moderators. Our synthesis demonstrated that exercise is effective at modulating aberrant food reward, with its outcomes jointly shaped by exercise protocols, personal traits and study design. Three interrelated regulatory axes were identified: (i) the cognitive-neural pathway that tunes mesolimbic dopamine, opioid and endocannabinoid signaling as well as prefrontal and hippocampal function; (ii) the physiological-endocrine pathway that balances gut hormones and microbiota while mitigating central insulin and leptin resistance and chronic inflammation; (iii) the psychological-behavioral pathway that strengthens inhibitory control, reduces food attentional bias and improves emotional regulation. Noticeable limitations including high outcome heterogeneity, insufficient causal evidence and the absence of personalized exercise schemes still restrict current research progress. We recommend future research to combine multi-dimensional reward measurements, multimodal omics and causal inference to unpack core mechanisms, and build phenotype-matched exercise regimens to advance obesity intervention from population-based strategies to individualized precision treatment.