Investigation of the effect of exercise on appetite and appetite hormones: A PubMed based systematic review

Appetite controls energy balance by affecting food intake. The appetite mechanism can be regulated by hormones secreted from various tissues. Hormones such as peptide YY, glucagon-like peptide 1, cholecystokinin, pancreatic polypeptide, oxyntomodulin, amylin, leptin are stimulated with food intake, and suppress appetite; while hormones such as ghrelin and glucagon are inhibited by food intake and increase appetite in case of hunger. Exercise can play a role in the appetite mechanism with its effect on appetite hormones. Exercise facilitates weight control through its effects on appetite regulation. Compared to one-off acute exercise studies, chronic exercise studies lasting more than 12 weeks may allow us to observe the possible effects of exercise on appetite hormones more clearly. However, there is large variability between individuals' responses. This article reviews the evidence for how BMI, gender, exercise intensity-type, pre-exercise food intake, and habitual physical activity alter exercise-related appetite and appetite-related hormone responses. Keywords "exercise and appetite", "exercise and appetite hormones", "physical activity and appetite" were used in the PubMed search engine for data search concerning human studies conducted in the last five years, using the PRISMA method. Research results reveal that BMI, habitual physical activity and exercise intensity do not significantly alter the appetite to acute or chronic exercise interventions. However, it has been shown that exercise type, pre-exercise food intake, and individuals in different gender groups provide different responses to exercise. The effect of these individual characteristics and behaviors, and exercise on appetite-related hormone responses remains unclear. Future well-controlled studies are needed to determine the possible effects of exercise on appetite and appetite hormones.