1. Introduction
cancer [Behaviors, Dietary behaviors, food-seeking behaviors, pancreatic and gastrointestinal hormones, satiety, dietary behaviors
SECONDARY, TYPE 2 DIABETES MELLITUS, CHRONIC DISEASES, HEART DISEASE
Hunger and satiety are controlled by several physiological mechanisms, including pancreatic and gastrointestinal hormones. While the influence of exercise and fasting have been described individually, in relation to these hormones, there is a paucity of work showing the effects of the two modalities (fasting and exercise) combined. Twenty healthy adults (11 males, 9 females) completed both conditions of this study, each consisting of a 36-h water-only fast. One of the fasts began with treadmill exercise, and the differences between the conditions on various appetite hormones were measured every 12 h. The difference in the area under the curve between conditions for ghrelin was 211.8 ± 73.1 pg/mL (F = 8.40, Dietary behaviors are linked to metabolic health and have been shown to predict non-communicable chronic diseases such as type 2 diabetes mellitus, heart disease, and cancer [Behaviors surrounding food consumption are influenced by a number of environmental, social, psychological, and physiological factors. This interplay between drivers of food consumption makes the control of dietary behaviors very complex and creates a challenge when attempting to regulate food intake. Physiologically, the drive to consume food is largely regulated by a balance of hormones that signal both satiety and hunger [During a period of fasting, circulating levels of GLP-1, PYY, PP, GIP, leptin, and insulin are reduced, and levels of antagonistic hormones such as ghrelin and glucagon increase. These changes in hormones drive food-seeking behaviors [While previous works have assessed the independent effects of fasting and exercise on hunger, to date there are only a few that have evaluated the two in combination [We previously published the primary outcomes of this study. These results show that initiating a fast with a bout of exercise accelerated some of the metabolic changes that occur during fasting [The aim of this study was to evaluate the impact of initiating a 36-h fast with or without a bout of exercise on plasma concentrations of ghrelin, GLP-1, GIP, PYY, PP, leptin, and insulin. We also describe the overall change in hormone concentrations over the course of a 36-h fast. These results represent secondary outcomes to data that has been previously reported [