This comprehensive network meta-analysis examined 235 randomized controlled trials involving over 20,000 older adults to determine the most effective combinations of protein supplementation and exercise for preventing sarcopenia. Whey protein combined with resistance training emerged as the superior intervention, producing large effect sizes for muscle mass (SMD 1.29) and leg strength (SMD 1.16). When paired with multicomponent exercise, whey protein also delivered the strongest improvements in functional mobility measures including chair rise performance and timed up-and-go tests. This finding carries substantial implications for aging populations, as sarcopenia affects up to 50% of adults over 80 and significantly increases fall risk, hospitalization rates, and mortality. The research landscape has long debated optimal protein types, with whey's rapid absorption and complete amino acid profile now validated against alternatives like soy and casein across diverse exercise modalities. However, the analysis reveals treatment efficacy varies significantly based on individual factors including baseline fitness, protein dosing, and participant characteristics. While this represents the most comprehensive evidence synthesis to date, the heterogeneity across studies and potential publication bias toward positive whey protein results warrant cautious interpretation of these promising findings.