Exercise Training and Metabolic Flexibility in Prediabetes

The Effect of an Exercise Training Program on Metabolic Flexibility in Older Adults With Prediabetes

The purpose of the study is to determine if a 6-week exercise training program promotes exercise-induced metabolic flexibility, that is, the ability to switch fuel sources for energy, in older prediabetic adults.

This is an investigator initiated single group intervention trial. All participants will receive a 6-week exercise training program with testing occurring before and following the training program. Participants will be provided with 3 days of a high fat diet prior to each of the three testing sessions at the Clinical Research Unit. All who agree to participate will undergo the same intervention.

The goal of this proposal is to study the impact of a 6-week moderate intensity walking training program on exercise induced lipid metabolic flexibility in older adults with prediabetes. Study Investigators will seek to determine if exercise induced lipid oxidation following a high fat diet is increased in trained individuals relative to their baseline.

Inclusion Criteria:

• ≥60 years of age
• Sedentary prior to the start of the training program (self-reported: less than 30 minutes of exercise for no more than 1 day a week)
• Prediabetes (measured at first screening: HbA1c = 5.7-6.5%)
• Must be able to pick-up and consume study provided foods
• Willingness to provide informed consent and participate in the intervention
• Must obtain transportation to visits and intervention training sessions
• No contraindications for involvement in a moderate exercise training program or exercise testing procedures by self-report

Exclusion Criteria:

• Self-reported diagnosis of a metabolic or chronic disease such as cardiovascular disease, diabetes, Chronic Obstructive Pulmonary Disease, or movement disorders such as Parkinson's disease, Ataxia, Huntington's Disease
• Current or recent (<12 months) treatment for cancer
• Body Mass Index <18.5 or >/30.0 kg/m2
• Tobacco users
• Febrile or chronic infection within study period
• Aversion to testing procedures
• Hypertension, hyperthyroidism, hypothyroidism
• Unwilling to abstain from ingesting caffeine during study testing periods
• Unwilling to withhold medications that affect metabolic rate during testing periods
• Physically active (>30 minutes per day on more than 1 day per week)
• ECGs that indicate cardiac injury or contraindications to treadmill testing
• Allergic or intolerant to any study-provided foods