The Impact of Energy Intake and Short-term Disuse on Muscle Protein Synthesis Rates and Skeletal Muscle Mass in Middle-aged Adults.
- Conditions
- Muscle AtrophyAgingEnergy Malnutrition Protein
- Interventions
- Other: Energy status
- Registration Number
- NCT04900701
- Lead Sponsor
- University of Exeter
- Brief Summary
In healthy middle-aged men and women, what is the effect of dietary energy restriction and energy surplus on daily muscle protein synthesis rates and muscle morphology, compared to energy balance, during free-living and immobilisation?
- Detailed Description
Background Age related muscle tissue loss, which is associated with a number of negative health outcomes is partially caused by blunted muscle protein synthesis rates (MPS) in response to food ingestion, which is exacerbated by muscle disuse. Concomitantly, consuming an energy balanced diet appears to become more challenging with advancing age, due to a reduction in appetite. Of concern is that the impact of energy intake on muscle protein metabolism during ageing is poorly characterised.
Objective To determine daily MPS and muscle morphology in response to differing energy intakes, in free-living conditions and during immobilisation.
Methods Healthy middle-aged volunteers will consume a hypocaloric, energy-balanced, or hypercaloric diet (providing 1.4 g.kg.day protein) over a three-day free-living period, and a three day period of single leg immobilisation. Deuterium oxide and MRI scans will be used to measure daily MPS and muscle size, respectively.
Value The study will determine the effect of energy intake per se on daily muscle protein synthesis rates and muscle size, in free-living and immobilised conditions. This will inform how energy provision modulates tissue loss with ageing, and how this interacts with the catabolic stress of muscle disuse.
Recruitment & Eligibility
- Status
- ACTIVE_NOT_RECRUITING
- Sex
- All
- Target Recruitment
- 36
Age 35-65 Healthy Non-smoker Recreationally active
Any diagnosed metabolic impairment (e.g. type 1 or 2 Diabetes) Any diagnosed cardiovascular disease or hypertension Elevated blood pressure at the time of screening. (An average systolic blood pressure reading of ≥150mmHg over two or more measurements and an average diastolic blood pressure of ≥90mmHg over two or more measurements.) Chronic use of diabetic medication. A personal or family history of epilepsy, seizures or schizophrenia. Allergic to mycoprotein / Quorn, penicillin, or cow's milk. Any musculoskeletal injury that may impair their use of crutches. Any diagnosed severe digestive illness. Any diagnosed severe autoimmune disease. Any diagnosed cancer. Any metal fragments in the eyes, a pacemaker, or metal implants in the body that preclude MRI scanning.
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- PARALLEL
- Arm && Interventions
Group Intervention Description Hypercaloric Energy status Participants placed in energy surplus. Hypocaloric Energy status Participants placed in energy restriction. Energy Balance Energy status Participants placed in energy balance.
- Primary Outcome Measures
Name Time Method Muscle protein synthesis (MPS) 6 days (3 days free-living, 3 days immobilised) Daily muscle protein synthesis rates, expressed as fractional synthetic rate (FSR) (%/day)
- Secondary Outcome Measures
Name Time Method Muscle morphology. 3 day immobilisation phase. Changes in muscle size, measured via MRI scanning, during immobilisation.
Trial Locations
- Locations (2)
University of Exeter, Sports & Health Sciences, College of Life & Environmental Sciences
🇬🇧Exeter, Devon, United Kingdom
Sport & Health Sciences University of Exeter
🇬🇧Exeter, Devon, United Kingdom