What was investigated?
An additional STEP UP analysis used MRI to assess thigh muscles. The group receiving semaglutide included 49 participants. Follow-up lasted 72 weeks. Body composition and the number of chair rises in 30 seconds were assessed. [64]
What do the measurements show?
The semaglutide group had less body fat and less fat within thigh muscles. However, no clear difference in change in thigh-muscle volume was demonstrated between those receiving semaglutide and those not receiving it. In the semaglutide group, the mean chair-rise test result increased from 13 to 15 repetitions. That measurement alone does not prove the medicine caused the functional improvement. [64]
What does this not establish?
The very small comparison group limits certainty about treatment effects on muscles across a broad patient population. Two semaglutide doses were also combined. No clear difference does not prove muscles always remain unchanged. One test does not describe all physical functioning. [64]
The study was funded by Novo Nordisk. The abstract was read through the PubMed index, not the full article. [64]
Where does this information come from?
Show sources and how they were checked
- Effect of Semaglutide on Thigh Skeletal Muscle Volume, Fat Infiltration and Physical Function in People With Obesity: Secondary Analysis of STEP UP
Study publication · online 20 September 2026 · PubMed abstract accessed through a search index; full text not reviewed · DOI: 10.1111/dom.71323. Accessed: 3 November 2026.