Greg Grosicki Study Links 12-Week GLP-1 Use to 3.2 bpm Heart-Rate Rise

2 articles · Updated · Men's Health · Jul 9

A 12-week study of 66 active adults found GLP-1 users lost body mass while resting heart rate rose 3.2 beats per minute and heart-rate variability fell 6.2 milliseconds.
HRV declines were statistically significant by week 4, suggesting recovery stayed impaired even as weight dropped—a pattern that can translate into worse endurance and higher effort at slower paces.
Sports dietitians said athlete responses vary, but growing use is outpacing guidance; one Division I program has already added GLP-1 screening to intake forms.
Low energy availability is a key concern because appetite suppression can leave training output ahead of calorie intake, raising risks of RED-S, poor recovery, mood changes and performance drag.
Grosicki said GLP-1s are not a shortcut for athletes: preserving muscle, fueling on schedule and monitoring metrics matter, while effects beyond 12 weeks remain unclear.

Sources

Men's Health18h ago

Greg Grosicki Study: GLP-1 Medications Negatively Impact Athlete Performance Metrics

AOL18h ago

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GLP-1 Agonists Raise Resting Heart Rate Despite Weight Loss: New 12-Week Study and What It Means for Patients and Athletes

Overview

The Grosicki study tracked 66 people starting GLP-1 receptor agonist medication and found that after 12 weeks, participants lost an average of 10% of their body weight and had a significant increase in resting heart rate by about 3 beats per minute. This heart rate rise was linked to a drop in heart rate variability, showing that GLP-1 RAs affect the autonomic nervous system and how the heart responds to daily life. Interestingly, people who increased their physical activity tended to have less of a heart rate increase, suggesting that exercise may help offset some cardiovascular effects of these medications.

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