Genetics play a crucial role in fitness performance by influencing factors such as muscle fiber composition, metabolism, and overall physical capability. Some individuals may naturally possess a higher percentage of fast-twitch fibers, which are advantageous for strength and power sports, while others may have more slow-twitch fibers that benefit endurance activities. Genetic predispositions determine not only athletic talent but also recovery rates and susceptibility to injuries. Understanding these factors can help tailor training regimens to maximize each person's potential in fitness.