Effects of Positive Energy Balance and Exercise on Appetite Hormones in Sedentary Men and Women

Inclusion Criteria: * Healthy body mass index (BMI) = 19 \< 25 kg/m2 * Obese BMI = 30 \< 35 kg/m2 * Activity level = sedentary: Total energy expenditure/resting metabolic rate \< 1.6 (average US adult level) Exclusion Criteria: * Tobacco use * Regular exercise or physical activity, defined as \> 2h/week of moderate to vigorous activity; * Individuals who do not eat breakfast * Weight loss of \> 3% of body weight over the previous six months * Eating a special diet (e.g., vegetarian or low-carbohydrate) * Current diagnosis of, or using prescription medications for, thyroid dysfunction, type I or type II diabetes, hypertension, cardiovascular, kidney, or liver disease; * Taking other prescription medications or over-the-country products that alter energy metabolism (other than birth control pills) * Allergies to any of the foods used in the study * Individuals who donated blood within 8 weeks prior to enrollment or who plan to give blood during the course of the study * Claustrophobia * History of exercise intolerance, including diagnosed exercise induced asthma or any physical limitations to seated cycling aerobic exercise * Blood chemistries in excess of 130% of the upper normal level and/or hemoglobin or hematocrit below the normal range. * Females that are pregnant (pregnancy status to be tested at the beginning of each 6-day metabolic chamber stay), lactating, or have irregular menses