Fitness training influences body composition through the development of muscle mass while promoting fat loss. Resistance training enhances muscle hypertrophy, increasing metabolic rate, which aids in burning calories even at rest. Regular aerobic exercise complements this effect by improving cardiovascular health and further contributing to weight management. By appropriately balancing cardio and strength training, individuals can achieve a healthier body composition over time. Moreover, understanding the importance of nutrition in supporting fitness goals is crucial to optimizing body composition and achieving desired physical outcomes.