Tesamorelin increases muscle area and density, especially in core muscles like abs and spinal extensors, while reducing fat infiltration inside the muscle, which is important for metabolic health.

Tesamorelin increases cross-sectional area and density of trunk skeletal muscles while reducing intramyocellular lipid infiltration.

Tesamorelin independently increases fat density in visceral and subcutaneous adipose tissue, indicating improved fat quality with smaller adipocytes, better vascularization, reduced hypoxia, and decreased inflammation, independent of fat quantity changes.

Tesamorelin increased rectus and psoas muscle size by 0.44 and 0.46 cm² in people with HIV and belly fat, and this effect remained even after accounting for belly fat loss.

For people with HIV and belly fat who responded to tesamorelin, the drug helped increase muscle density in their trunk muscles by 1.56 to 4.86 units compared to those who didn't take it.