Muscle strength and mass are among the strongest predictors of longevity and healthspan, with grip strength showing a 16% increase in mortality risk per 5kg reduction. This comprehensive AMA distills 30+ hours of expert discussions into practical strategies for building and maintaining muscle safely across all ages, covering progressive overload, nutrition, power training, and recovery—essential knowledge for anyone seeking to live longer and better. Grip strength predicts all-cause mortality more reliably than many established health markers; every 5kg reduction in grip strength correlates with a 16% increase in mortality risk across 140,000 people in 17 countries.