Exercise Impact on Dietary Protein Efficiency in Older Adults With Type 2 Diabetes
In this randomized controlled trial, 30 older adults (aged\> 65 years; 15 with T2D, 15 controls) will participate in a 12-week progressive exercise training program. They will undergo pre- and post-testing that includes body composition measures; oral glucose tolerance testing; cardiovascular fitness and muscle performance testing; dietary protein efficiency assessed using the indicator amino acid oxidation (IAAO) method; and a gut microbiota trial. The dietary protein efficiency trial will include repeated ingestion of crystallized amino acids (drink) containing stable isotopes, urine samples, and breath samples. The gut microbiome trial will consist of a single ingestion of a Mediterranean-based modeled meal enriched with 13C-phenylalanine (in the drink) and repeated blood draws. Participants will also be asked to give a fecal sample after the gut microbiome trial.
⁃ At least 65 years old
⁃ Body mass index: 25-40 kg/m\^2
⁃ Female: Waist to hip ratio \>0.8
⁃ Male: Waist to hip ratio \>1.0
⁃ Free from structured exercise during the prior 6 months (mo) weight stable for the prior 6 months
‣ T2D group:
• Diagnosed by a physician with elevated glycosylated hemoglobin (HbA1c) \>6.5%
‣ Control group:
• Normoglycemic with HbA1c levels not exceeding 5.6% and fasting blood glucose levels below or equal to 99 mg/dL (5.5mmol)