Study of Inactivity on Metabolism of Elderly Muscles

NCT01818609 | Completed Phase 1 DMC

• 1 other identifier: 267
• Study Type: interventional
• Target: 10
• Locations: 1 country
• Sites: 1

Brief Summary

Skeletal muscle mass declines with inactivity (casting is a good example) and increases with activity (such as weightlifting). Whether muscle mass increases or decreases, is determined by whether more new proteins within muscle are made than are broken down. The investigators know that feeding protein increases the synthesis of new proteins but that the response of older muscles to protein feeding is blunted compared with the young. This resistance of the elderly to muscle building stimuli may be the primary reason that muscle mass is lost in aging. The investigators also know that periods of muscle disuse such as casting result in a person's muscle shrinking due, the investigators believe, to a lower rate of synthesis of new muscle proteins. Age-related muscle loss begins around 50 years old and proceeds at approximately 1% for every year after. Elderly persons would likely fare well with advancing age if their muscle loss were simply linear; however, a rate of muscle loss of 1% annually is a 'population view' and does not represent what occurs during short periods of muscle disuse (i.e. during hospitalization or illness), which occur with increasing frequency in elderly persons. During periods of disuse, the resistance of elderly muscles to protein nutrition may be worsened. The investigators will measure how quickly new proteins are made at rest and after protein feeding in elderly men, before and after a 14 day period of reduced activity brought on by having people reduce their daily step count.

Conditions

Sarcopenia

Keywords

sarcopenia; muscle; reduced activity; insulin sensitivity; protein; step reduction; muscle protein synthesis; whey protein; leg strength; whole body protein

Outcome Measures

Primary Outcomes (1)

• Fractional synthetic rate (FSR) of myofibrillar muscle protein

  rate of making new muscle proteins

  over 5h

Secondary Outcomes (3)

• Blood amino acid concentrations

  over 5h

• Intramuscular signalling protein status

  over 5h

• Insulin sensitivity via blood sampling

  over 5h

Study Arms (1)

Step Reduction

EXPERIMENTAL

Step reduction: * Take less than 1500 steps/d * No disease

Behavioral: Step reduction

Interventions

Step reduction BEHAVIORAL

taking less than 1500 steps/d

Also known as: Sedentary behaviour

Step Reduction

Eligibility Criteria

• Age: 60 Years - 80 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Male or Female
• Aged 60 to 80 years old
• Non-smoker Generally healthy and can tolerate the resistance exercise and protein drink

You may not qualify if:

• Allergies to whey protein
• Health problems such as: heart disease, rheumatoid arthritis of the knee joint, diabetes, poor lung function, uncontrolled hypertension, or any health conditions that might put participants at risks for this study
• Failed an exercise stress test
• Taking metformin and/or other medications for the control of blood glucose even though one might not be classified as diabetic
• Taking prescribed blood thinners such as warfarin and heparin but excluding aspirin
• Taking medications for lung and kidney conditions but excluding medication for asthma that is under control

Sponsors & Collaborators

• McMaster University: lead

Study Sites (1)

McMaster University

Hamilton, Ontario, L8S 4K1, Canada

Location

MeSH Terms

Conditions

Sarcopenia; Insulin Resistance

Condition Hierarchy (Ancestors)

Muscular Atrophy; Neuromuscular Manifestations; Neurologic Manifestations; Nervous System Diseases; Atrophy; Pathological Conditions, Anatomical; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Hyperinsulinism; Glucose Metabolism Disorders; Metabolic Diseases; Nutritional and Metabolic Diseases

Study Officials

• Stuart M Phillips, PhD

  McMaster University

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: phase 1
• Allocation: NA
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: July 19, 2011
• First Posted: March 26, 2013
• Study Start: September 1, 2011
• Primary Completion: September 1, 2012
• Study Completion: December 1, 2012
• Last Updated: February 25, 2020

Record last verified: 2013-03

Locations

CA (1)