A caloric surplus occurs when an individual consumes more calories than their body expends, leading to weight gain. This surplus is necessary for muscle building, especially in strength training. However, excess calories can also lead to fat accumulation if not monitored. Maintaining a stable caloric surplus promotes healthy weight gain in athletes or individuals looking to bulk up, but if not managed properly, it can contribute to obesity and associated health issues. Thus, understanding and controlling caloric intake is essential for achieving fitness and health goals.