Short Term Effects of Semaglutide on Body Composition and Performance

What Was Tested

The trial (not phased) is built around Semaglutide.

This randomized placebo-controlled parallel intervention study aims to investigate the short-term effects of semaglutide on body composition, muscle mass, volume and function, running economy, and performance in well-trained male and female runners.

It had two arms (groups): Semaglutide (experimental) and Placebo (placebo comparator).

Participants will receive semaglutide treatment for 4 weeks.

Participants will receive placebo treatment for 4 weeks.

The registry classes the interventions as drug.

More on the Plan

Before and after the intervention period, participants will complete 2 experimental days (4 experimental days in total).

On experimental days, change in body composition, with a particular focus on muscle mass, will be assessed using DXA scans and ultrasound imaging of v. lateralis.

Furthermore, specific performance tests (200-m, 3-km, 10-km) as well as running economy will be measured.

Who Took Part

41 planned participants were the target.

It was open to people of any sex aged from 18 years up to 45 years.

Healthy volunteers could join, not only people with the condition.

Examples of who could join: Healthy experienced triathletes or distance runners (training history +5 years and weekly training volume \>10 h/week). Aged 18 to 45 years. Body mass index (BMI) between 21.0-26.0 kg/m2.

The full record lists 3 inclusion and 6 exclusion criteria; among the exclusions: chronic use of medication (except for occasional use of analgesics or antihistamines); chronic disease (e.g. diabetes, disordered eating behavior (ede-q \>2.5 for females and 1.7 for males)); abnormal kidney function, or ecg abnormalities.

How the Study Was Run

It was run as a randomized, parallel-group and triple-blind study.

The participants were allocated by chance, so the Semaglutide group and the comparison group should start out alike.

Groups ran in parallel: each of the participants stayed in one arm throughout.

Blinding on both sides kept the participants and researchers unaware of who received Semaglutide.

Those kept unaware of assignments: participant, care provider and investigator.

It started in 2026-10-14 with completion listed for 2027-12-31.

It ran at 1 site in Denmark.

Its stated primary purpose is basic science.

What Was Measured

Primary outcome: Change in total lean mass measured by dual-energy X-ray absorptiometry (DXA) (time frame: Baseline (week 0) and immediately after the 4-week intervention period (week 4)).

It also tracked 4 secondary outcomes, for example Change in muscle thickness measured by ultrasonography, Change in running performance, Change in maximal voluntary isometric quadriceps contraction torque and Change in one-repetition maximum (1RM) leg press strength.

What This Means in Plain Language

Put simply, this is a not phased, randomized trial of Semaglutide in 41 people.

Its status is not yet recruiting; no results are posted to the registry yet, so nothing here describes outcomes.

More context: the Semaglutide compound page, all human trials.