Factors that influence muscle growth include resistance training intensity, nutrition, and recovery time. Progressive overload, which involves gradually increasing resistance or weight in exercises, is essential for stimulating muscle fibers. Adequate protein intake plays a crucial role in muscle repair and growth, making nutrition fundamental for anyone striving for hypertrophy. Hormonal levels, particularly testosterone and growth hormone, also contribute to muscle development. Additionally, recovery periods allow muscles to heal and adapt, underscoring the importance of rest days and sleep in any effective muscle-building regimen.