Exercise decreases among people taking GLP-1 medication

Adults with obesity using GLP-1 receptor agonist medications significantly decreased their physical activity, according to a study presented Saturday at ENDO 2026. Data showed average daily steps fell from 5,047 to 4,487, suggesting that weight loss from these drugs does not naturally lead to increased exercise.

The study, presented at the Endocrine Society’s annual meeting in Chicago, Ill., focused on medications including semaglutide, liraglutide, dulaglutide and tirzepatide. These drugs reduce both fat and lean muscle mass, making physical activity critical for preserving strength, according to study lead Sajana Maharjan, M.D., of HSHS St. John’s Hospital in Springfield, Ill.

Why did physical activity decrease during GLP-1 treatment?

Researchers found that daily steps and moderate-to-vigorous physical activity (MVPA) minutes both declined after patients started treatment. MVPA minutes dropped from an average of 28 to 22 per day.

The largest declines occurred in men and individuals reporting joint or muscle pain. Other factors, including age, prior stroke or heart failure, did not change these results.

Did You Know? This is the first large study to analyze data from wearable fitness trackers specifically among adults taking GLP-1 receptor agonists.

How was the study conducted?

The retrospective pre–post cohort study used data from the National Institutes of Health’s All of Us Research Program. This program links electronic health records with Fitbit activity data.

Out of 1,950 adults with obesity who began GLP-1 medication, researchers analyzed 753 people with sufficient wearable-device data. The group was 78.6% female with a mean age of 52.7 years.

Expert Insight: Samantha Carter notes that the loss of lean muscle mass alongside fat creates a significant health trade-off. Because these medications don’t automatically trigger more movement, the risk of losing strength could outweigh the benefits of weight loss if exercise isn’t prioritized.

What may happen next for patients on these medications?

Because weight loss did not lead to increased activity, patients may require targeted interventions to encourage exercise. Maharjan stated that exercise “cannot be optional” for those using these medications.

Clinical approaches could shift toward combining GLP-1 prescriptions with structured physical activity plans to protect long-term health and muscle preservation.

Frequently Asked Questions

Which specific medications were included in the study?
The study looked at GLP-1 receptor agonists including semaglutide, liraglutide, dulaglutide and tirzepatide.

Did weight loss make patients more active?
No. The study found no evidence that weight loss from these medications led to increased physical activity.

Who experienced the most significant drop in activity?
The largest declines in physical activity were seen in men and people suffering from muscle or joint pain.

Do you think exercise should be a mandatory part of weight-loss medication prescriptions?