An individual experiencing muscle dysmorphia is primarily concerned with:

Muscle dysmorphia is a condition often observed in individuals, particularly among those who engage in bodybuilding and fitness-related activities. It is characterized by an intense preoccupation with perceived deficiencies in muscle size or definition, leading to an exaggerated pursuit of muscle gain. People with muscle dysmorphia typically see themselves as smaller or weaker than they actually are, which drives them to engage in extreme behaviors aimed at increasing their muscle mass.

The focus on extreme muscle gain manifests in various ways, including rigorous exercise regimens and the use of supplements or anabolic steroids, aimed at achieving an idealized physique that they believe they lack. This condition differs significantly from simply wanting to lose weight or improve cardiovascular fitness; rather, it revolves around an obsessive desire to bulk up and enhance muscularity.

Thus, the correct choice reflects the primary concern for individuals dealing with muscle dysmorphia, as it encapsulates their psychological battle with body image and the resulting behaviors aimed at achieving greater muscle mass.