What would cause a beginning exerciser to experience weight gain without an accompanied increase in storage fat?

Question

Quizplus · Accepted Answer

An increase in muscle tissue can lead to weight gain without an increase in storage fat because muscle is denser than fat. As a person begins exercising, especially with strength training, they may build muscle mass which can cause the scale to go up even as their body becomes leaner and healthier.

What Would Cause a Beginning Exerciser to Experience Weight Gain