Exogenous Ketosis During Bed Rest in Older Adults

The goal of this randomized, double-blind, parallel group interventional study is to evaluate the effect of ketone bodies on healthy older adults (65-85 y) during 5 days of bed rest. The main questions it aims to answer are:Does supplementation of ketone bodies prevent the typical decline in muscle protein synthesis, muscle size, muscle function, insulin sensitivity, and muscle mitochondrial function that occurs in response to bed rest?Researchers will compare ketone supplements (KET) to an energy matched control beverage (carbohydrates and fats) to see if the ketones can rescue the decline in muscle protein synthesis rates, muscle loss, muscle function, insulin sensitivity, and mitochondrial function due to 5 days of bed rest.This may positively impact the heath of older adults subjected to bed rest.

Inclusion Criteria:Healthy, male, and female, older adults.Healthy will be defined as screen by the 2020 PAR-Q+, medical screening questionnaire, GAQ, and COVID-19 symptom questionnaire patient screening.'Older' will be defined as being 65-85 years of age.Participants are required to not engage in structured resistance training for at least 6 months prior to participation in the study.Participants are willing to abide by the compliance rules of this study.Exclusion Criteria:Pre-menopausal females: Women must be postmenopausal having not menstruated for at least 1 year prior to study participation. Hormonal fluctuations associated with the menstrual cycle have been reported to alter protein metabolism and may influence indices of muscle protein synthesis and breakdown (69-71).BMI <18.5 or > 30 kg ∙ m-2.Self-reported regular tobacco use and vaping products.Self-reported illicit drug use (e.g., growth hormone, testosterone, etc.)Individuals who have participated in studies within the past year involving a stable isotope of 2H.A history of thrombosis, diagnosed with type 2 diabetes mellitus by physician or HbA1c values of > 7.0%, dementia, coronary artery disease, musculoskeletal/orthopedic disorders, and severe allergies.The use of medications known to modulate skeletal muscle metabolism (e.g., corticosteroids, hormone replacement therapy, non-steroidal anti-inflammatory drugs, metformin).The use of over-the-counter supplements (protein supplements, creatine, fish oil).Inability to adhere to any of the compliance rules judged by the principal investigator or medical doctor.