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Getting the latest healthcare news for you

Patients on GLP-1 medications are moving less, not more, despite weight loss — and the data backs it up. New studies using Fitbit data show significant drops in daily steps and moderate-to-vigorous activity after starting GLP-1 therapy. Experts say exercise must be actively prescribed alongside these medications, not assumed to follow naturally from shedding pounds.
You'd think losing weight would make people want to move more — but new research says the opposite is happening with GLP-1 users. Two studies using objective Fitbit data from the NIH's All of Us Research Program found that patients with obesity significantly reduced their physical activity after starting GLP-1 therapy. Daily step counts dropped from ~5,047 to ~4,487, and moderate-to-vigorous physical activity (MVPA) fell from 27.9 to 22.2 minutes per day. A separate cross-sectional study found that over half of GLP-1 users weren't meeting the recommended 150 min/week of MVPA — and their average sedentary time clocked in at nearly 16 hours a day, far above the U.S. population average of ~9.7 hours.
Why the decline? Researchers point to several compounding factors: reduced calorie intake leaving less energy for movement, early side effects like nausea and fatigue, lean muscle loss reducing exercise capacity, and a behavioral perception that the medication is "handling" the weight loss.
Key Takeaways:
Why it matters: GLP-1s reduce both fat and lean muscle mass, making physical activity more critical — not less — during treatment. Clinicians are urged to actively prescribe structured exercise, offer resistance training guidance, and address barriers like pain and low motivation, rather than assuming weight loss will naturally drive patients to move more.