Define the term "muscular hypertrophy."

Muscular hypertrophy refers specifically to the increase in the size of skeletal muscle fibers as a result of resistance training and other forms of physical exercise. When muscles are subjected to stress, such as lifting weights, they undergo micro-tears and respond by repairing themselves, which leads to an increase in the size of the muscle fibers. This adaptation not only enhances the aesthetic appearance of the muscles but also contributes to greater strength and endurance capabilities.

In this context, the other options relate to different concepts or outcomes that do not accurately define muscular hypertrophy. For example, a decrease in muscle strength contradicts the general outcome of hypertrophy, which typically results in increased strength. Improvement of muscle coordination is more related to neuromuscular adaptations rather than size increases. Lastly, while fat content can affect muscle definition, it does not define the process of hypertrophy itself. Therefore, the correct definition accurately captures the essence of what muscular hypertrophy entails.