Whey protein supplementation and exercise in older adults: a narrative review of potential effects on muscle-brain...

Aging is associated with progressive declines in cognitive function, physical performance, and musculoskeletal integrity, increasing the risk of frailty and injury. Recent evidence highlights the importance of the muscle-brain-metabolism axis in mediating these age-related changes. Interventions targeting this axis, including whey protein supplementation combined with structured exercise, have attracted growing attention. This narrative review summarizes current evidence regarding the combined effects of whey protein and exercise on physical performance, muscle health, and selected biomarkers in older adults, while also discussing emerging findings related to cognitive function and injury risk. Mechanistically, these interventions may support muscle protein synthesis, modulate inflammatory pathways, improve metabolic regulation, and influence neurotrophic signaling. However, current evidence regarding cognitive outcomes and injury prevention remains limited and, in some cases, inconsistent, with many studies reporting these outcomes as secondary endpoints. Therefore, while combined interventions show potential for improving aspects of healthy aging, further well-designed studies are required to establish their effectiveness in these domains. Overall, targeting the muscle-brain axis through nutritional and exercise-based strategies represents a promising but still evolving approach for supporting healthy aging and functional capacity in older adults.