The objectives of this study are to demonstrate that real time physiological status monitoring and the use of optimization techniques during exercise can have a positive impact on physiological status, and to collect metabolic flexibility profiles of young fit adults during rest and exercise.

This experiment aims to accomplish two goals: collect additional metabolic flexibility data with young fit adults in response to exercise; and demonstrate that automated pace guidance generated from real-time thermal-work strain monitoring and an optimized pacing policy will allow less stressful completion of a timed (60 minute) treadmill exercise of 5 miles. Each participant will undergo two treatments of first UNGUIDED followed by GUIDED exercise. The two exercise sessions will be conducted as part of a ~24 hour stay in an indirect calorimetry chamber.

Inclusion Criteria:

• Male and Female
• Ages 18 to 29 at the beginning of the study
• Relatively fit can run 2 miles in under 16 minutes

Exclusion Criteria:

• History of Skin Sensitivity to Nickel
• Hypertension
• Alcoholism
• Diabetes
• Pregnant
• Age >29
• Cannot run 2 miles in less than 16 minutes
• No regular weekly exercise
• Difficulty Swallowing Food or Large Pills
• Diverticulitis
• Inflammatory Bowel Disease
• Peptic Ulcer Disease
• Crohn's Disease
• Ulcerative Colitis
• Previous Gastrointestinal Surgery
• Possible Nuclear Magnetic Resonance Scan
• Women who have given birth during the previous 12 months
• Pregnant women or women who plan to become pregnant or become pregnant during the study
• Lactating women
• History or presence of kidney disease, liver disease, certain cancers, gastrointestinal, pancreatic, other metabolic diseases, or malabsorption syndromes
• History of bariatric or certain other surgeries related to weight control
• Smokers or other tobacco users (for at least 6 months prior to the start of the study)
• History of eating disorders or other dietary patterns which are not consistent with the dietary intervention (e.g., vegetarians, very low fat diets, high protein diets)
• Volunteers who have lost 10% of body weight within the last 12 months or who plan to initiate a weight loss program during the next 10 months
• Unable or unwilling to give informed consent or communicate with study staff.
• Self-report of alcohol or substance abuse within the past 12 months and/or current acute treatment or rehabilitation program for these problems (long-term participation in Alcoholics Anonymous is not an exclusion)
• Other medical, psychiatric, or behavioral factors that in the judgment of the Principal Investigator may interfere with study participation or the ability to follow the intervention protocol
• Blood donation within the previous month