Nutrition and physical activity countermeasures for sarcopenia: Time to get personal?

Population ageing is a global phenomenon. It is regarded as a major cause of upward pressure on healthcare costs. One of the greatest threats to healthy, independent ageing is sarcopenia, the progressive loss of skeletal muscle mass and function with age. Physical inactivity and poor nutrition represent crucial and imminently modifiable risk factors for sarcopenia. Resistance exercise training is the most effective method for improving muscle mass and function in older adults. Evidence indicates that resistance training-induced improvements in muscle mass, strength and function may be further augmented by certain nutrients and nutritional strategies. Ageing is associated with a reduction in the anabolic sensitivity of skeletal muscle to dietary protein ingestion and accumulating evidence indicates that older adults require protein intakes 50%-100% higher than the recommended daily allowance (0.8 g/kg/day) to preserve muscle mass and function. Protein quality, the pattern of protein intake over the day (i.e. per-meal protein), specific amino acids (i.e. leucine) and other nutrients (i.e. vitamin D, long-chain n-3 polyunsaturated fatty acids) are also key considerations. From the personalised nutrition perspective, it is now acknowledged that individual responses to nutrition/exercise interventions are highly variable, despite equivalent compliance, thus highlighting the inadequacy of a 'one-size-fits-all' approach. The application of personalised medicine to sarcopenia represents an exciting emerging field of research with the potential to dramatically improve patient outcomes. This approach makes use of recent developments in 'omics' technologies and aims to identify the factors (i.e. genes, key biomarkers, medical history, environment, lifestyle) that determine whether an individual is a higher or a lower responder to a particular intervention. This narrative review discusses current evidence regarding nutrition and exercise countermeasures for sarcopenia, with a specific emphasis on recent developments in personalised approaches.