Research Studies

If you join the study, you will undergo screening evaluations to see if you are eligible to be in the study. If you are eligible to be in the study, you will be randomized to one of two study groups. Which group you are assigned to will be chosen by chance by a procedure similar to the toss of a coin. Both study groups will receive an identical aerobic exercise training program which lasts 13 months. One group will be asked to complete all exercise sessions in the morning (6-10 AM) and the other group will be asked to complete all exercise sessions in the late afternoon/evening (3-7 PM). The exercise training will progress to burning 2000 calories per week with moderate to vigorous intensity aerobic exercise. Both AM and PM exercise groups will perform 4 sessions of exercise per week during their randomized exercise time. You will wear a heart rate monitor for all exercise sessions and your exercise data will be viewed by study staff. During the first 7 months of the exercise program, three exercise sessions per week will be “supervised”, which means they will be monitored by study staff and completed at the Anschutz Health and Wellness Center (AHWC) exercise facility. During the first 7 months of the exercise program, one additional exercise session per week will be completed “on-own”, which means that you will be able to exercise at another location if you want. After you complete the first 7 months of the exercise program, you will be asked to perform 4 exercise sessions per week on your own for another 6 months. You will be asked to continue exercising during your randomized group time (AM or PM) and continue to wear the heart rate monitor during exercise. We will provide you with a membership to the AHWC exercise facility during this entire 13 month exercise program. Your participation in the study will last approximately 16 months to complete all study measures including study screening and baseline testing. During the study, you will be asked not to participate in any other weight loss, exercise, or diet programs and not to participate in any other research studies that might change your weight. During the study, you will be asked not to take any weight loss medications or weight loss supplements. If you are a female and you can become pregnant, you will be asked not to become pregnant and to use a reliable method of birth control during the study.