null RI-MUHC research team to study the health impact of inactivity

José Morais, MD,is  a member of the Metabolic Disorders and Complications Program at the Research Institute of the McGill University Health Centre A CIHR-funded project led by Dr. José Morais will investigate inactivity-induced muscle loss and the protective effects of exercise

April 11, 2019

(Source: RI-MUHC) Thanks to new funding from the Canadian Institutes of Health Research (CIHR), a team led by José Morais, MD, a member of the Metabolic Disorders and Complications Program (MeDiC) at the Research Institute of the McGill University Health Centre (RI-MUHC), will investigate the metabolic and molecular mechanisms underpinning inactivity-induced muscle loss and the underlying protective effects of an exercise countermeasure. 

Between 15 and 30 percent of the older population suffers from frail aging, a condition of decreased physiological reserves below the level normally expected with aging. This condition puts older adults at risk for adverse events, morbidity and mortality. Multiple trajectories can be associated with the development of frailty, including one, potentially, of intermittent bed-rest periods that are associated with acute diseases and hospitalizations leading to muscle loss. 

“Inactivity due to bed rest is particularly problematic for older adults, since they are already at an increased risk for reduced muscle and bone mass— in other words, sarcopenia or osteoporosis,” says Dr. Morais. “Exercise is a powerful countermeasure against the deleterious effects of inactivity on skeletal muscle protein metabolism, insulin sensitivity, and muscle loss. However, the underlying mechanisms have not been clearly defined,” he adds. In a randomized clinical trial of bed rest with and without exercise, the team will use state-of-the-art stable isotope methods combined with muscle biopsies to measure rates of muscle protein synthesis and breakdown to define the time course of muscle protein turnover changes. 

Sponsored by three CIHR Institutes – the Institute of Aging (IA), Institute of Circulatory and Respiratory Health (ICRH), Institute of Musculoskeletal Health and Arthritis (IMHA) – and in partnership with the Canadian Frailty Network (CFN) and Canadian Space Agency (CSA), the project will run in parallel and integrated into an overall coordinated protocol with seven other newly funded research projects.

The CSA will cover all basic infrastructure costs, including standardized measurements on participants, a medical team, and surveillance on site at a specific bed rest facility. The teams are allotted 18 months to prepare their study and coordinate with the bed-rest facility experts, to initiate and terminate their data collection during the bed-rest paradigm, and to analyze their data and prepare reports.

“Although it represents a challenge, we have gathered a robust and complementary team of investigators to execute such complex and demanding protocol. Indeed, clinical expertise in geriatrics, exercise physiology, metabolism and nutrition meet with core basic expertise in proteolysis, autophagy, mitochondrial function and bone homeostasis in our team,” says Dr. Morais. 

“Ultimately, this research will contribute to our knowledge of etiology of sarcopenia and frailty, and identify potential targets for future drug development. It will also provide evidence to improve clinical practice in hospitalized older adults and for programs in long-term care institutions,” he concludes.


CIHR Operating Grant: Priority Announcement Understanding the Health Impact of Inactivity
Proposal title: Unraveling the mechanisms underlying of bed rest-induced muscle atrophy and of an exercise countermeasure
Randomized controlled trial (RCT), $141,085 for 18 months

Research Team
Principal investigator: José Morais, MeDiC Program, RI-MUHC

Research Funding Announcement
Geriatric medicine: Responding to the health care needs of Canada's aging population
For more information please contact Guy Boutros (