Exogenous Ketosis During Bed Rest in Older Adults
Condition: Muscle Protein Synthesis; Muscle Atrophy; Insulin Sensitivity; Mitochondrial Function; Physical Inactivity; Cognitive Function; Muscle Strength; Functional Capacity
MeSH terms: Muscular Atrophy; Insulin Resistance; Hypersensitivity
Study type: Interventional

Summary: 
      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.
    

Detailed description: 
      Bed rest is a common feature of many clinical environments such as hospitals and long-term
      care facilities. However, physical inactivity due to bed rest decreases muscle size, muscle
      strength, and physical performance (i.e. rising from a chair) that can lead to a reduced
      quality of life and a higher risk of disease and death. Eating protein-rich foods and
      exercising normally helps to maintain muscle size by building proteins found in muscle.
      However, during bed rest there is a reduction in the rate at which proteins found in muscle
      are made and this leads to smaller muscles. Bed rest leads to problems with blood glucose
      regulation and insulin resistance which can increase the risk for diabetes. Both the loss of
      muscle size and insulin resistance are linked to problems with parts of our cells called
      mitochondria. Mitochondria do a lot of important things including keeping our cells full of
      energy. Bed rest occurs more frequently in older adults and also negatively impacts their
      health more than in younger adults. Sadly, there are limited options to prevent the problems
      associated with bed rest. Ketone bodies are molecules that come from fat that are normally
      produced in the body in response to reduced carbohydrate intake (i.e. a ketogenic diet).
      Recently ketone supplements have become available, which increase the amount of ketone bodies
      in the body without the need to limit carbohydrate intake from food. Elevated ketone bodies
      may help protect muscle size and health during bed rest by enhancing the process of building
      muscle proteins, improving blood glucose regulation, and helping mitochondria work optimally.
    

Intervention name(s): ketone monoester (R)-3-hydroxybutyl (R)-3- hydroxybutyrate; carbohydrate-fat placebo (fructose, corn and canola oil 50:50 ratio)
Intervention type(s): Dietary Supplement; Dietary Supplement
Intervention description(s): Provided twice a day between meals.; Provided twice a day between meals.
Other intervention name(s): delta G Oxford Ketone Ester
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: Randomized, double-blind, parallel group study design.
Masking: Triple (Participant, Investigator, Outcomes Assessor)
Primary purpose: Prevention
Keywords: Bed rest; Muscle protein synthesis; Older adults; Muscle mitochondrial function; Insulin sensitivity; Ketone bodies