Are Canadian protein and physical activity guidelines optimal for sarcopenia prevention in older adults?

Abstract

Aging is characterized by physiological and morphological changes that affect body composition, strength, and function, ultimately leading to sarcopenia. This condition results in physical disability, falls, fractures, poor quality of life, and increased health care costs. Evidence suggests that increased consumption of dietary protein and physical activity levels, especially resistance exercise, can counteract the trajectory of sarcopenia. Canadian guidelines for protein intake and physical activity were last updated in 2005 and 2011, respectively, and new evidence on sarcopenia diagnosis, prevention, and treatment is rapidly evolving. Protein recommendations are set as "one-size-fits-all" for both young and older adults. Recent evidence demonstrates that current recommendations are insufficient to meet the minimum protein requirement to counteract muscle loss and to stimulate hypertrophy in healthy older adults. Beyond quantity, protein quality is also essential to benefit muscle anabolism in older adults. In terms of physical activity, resistance exercise training is a potential strategy to counteract age-related effects, as it can elicit muscle hypertrophic response in addition to increases in muscle strength and function in older adults. Canadian physical activity guidelines lack details on how this modality of training should be performed. Current guidelines for protein intake and physical activity do not reflect recent knowledge on sarcopenia prevention. The gap between guidelines and the latest evidence on the maintenance and promotion of older adult's health highlight the need for updated protein and physical activity recommendations.