Grant: Operating Grant: Understanding the Health Impact of Inactivity

As evidenced in astronauts returning from a space camp mission, muscle disuse occurs in elderly and frail individuals through the same mechanisms. As the actual scientific research era hinges on patient-centered outcomes, it is equally important to develop tools that are scientifically reliable and of interest and at the patient's benefit. As muscle disuse leads to deleterious and unwanted consequences, there is a momentum to develop countermeasures to initiate prevention. As such, although exercise was proposed as a very efficient strategy to offset the impact of inactivity in those patients, reliable tools to manage its regimen and to evaluate its efficiency are still expected. The SAFE trial focuses on important surrogate outcomes of muscle wasting and loss of function. Eligible healthy participants, aged 55-65 years old, will randomly be allocated to the control (physiotherapy + psychological support) or intervention (physiotherapy + psychological support + 60 min of exercise/day) arms of the study. Trial will be conducted in the context of a bed rest laboratory, where participants will be lying down in bed on a 24/7 regimen during 14 days. Using pragmatic samples (blood and muscle biopsies), to facilitate the future implementation in the clinic, inflammation markers and neuromuscular activity and function will be assessed. Participants will be assessed at 7 days, 4 weeks and 4 months post-intervention. Conclusive evidence that the proposed markers and sophisticated measures accurately monitor neuromuscular changes would certainly change the management of these patients by physicians and therapists during space flight or in context of frailty. The success of the SAFE trial will be secured through the collaboration of a multidisciplary team composed of trainees, young, mid-career and senior researchers with expertise in aging, exercise and muscle function and biostatistics.