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Updated: May 22, 2026
A Novel Digital Platform for a Monitored Home-based Cardiac Rehabilitation Program
Published on: April 19, 2019
Body Composition Changes in Patients on GLP-1 Receptor Agonists Undergoing an Intensive Cardiac Rehabilitation
Ian Jennings1, Kristine Ly1, Mariam Marooki1
1UC San Diego School of Medicine, La Jolla, CA, United States, 9300 Campus Point Drive #7414, La Jolla, California 92093.
Background:
Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) are widely used for type 2 diabetes and obesity and produce significant weight loss. However, concerns have emerged about potential loss of skeletal muscle mass (SMM) with pharmacologic weight reduction, particularly in older adults at risk for sarcopenia. The effects of GLP-1 RA therapy on SMM among patients participating in Intensive Cardiac Rehabilitation (ICR) remain incompletely characterized.
Methods:
We performed a retrospective cohort study of 468 patients enrolled in a structured Pritikin ICR program at UC San Diego Health between 2017 and 2024. At program initiation, 67 patients were taking GLP-1 RAs with a median duration of 231 days (IQR 144-400). Body composition was assessed using bioelectrical impedance analysis (BIA) at baseline and program completion. Outcomes included SMM and fat mass (FM). Multivariable regression models adjusted for age, sex, baseline body mass index, diabetes status, and baseline fitness (measured in METs).
Results:
Both groups improved in metabolic equivalents of task (METs) with ICR (p < 0.001). At baseline, patients on GLP-1 RAs had higher BMI and percent body fat compared with non-users, but no differences in SMM. In adjusted analyses, GLP-1 RA use was not associated with significantly different percent change in SMM from baseline to ICR program completion compared with no GLP-1 RA use (β = 0.62%, 95% CI -0.62 to 1.86; p = 0.326). Similarly, there was no significant between-group difference in percent change in fat mass (β = 3.01%, 95% CI -1.64 to 7.66; p = 0.204).
Conclusions:
GLP-1 receptor agonist use during intensive cardiac rehabilitation was not associated with significantly different skeletal muscles mass changes after adjustment for measured covariates. These findings support the integration of GLP-1 based pharmacotherapy with structured exercise programs.
Insights
Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) did not significantly alter skeletal muscle mass (SMM) in patients undergoing intensive cardiac rehabilitation. This suggests GLP-1 RA therapy can be safely combined with structured exercise programs.
Area of Science:
- Cardiology
- Endocrinology
- Metabolic Health
Background:
- Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) are effective for type 2 diabetes and obesity, promoting weight loss.
- Concerns exist regarding potential skeletal muscle mass (SMM) loss with pharmacologic weight reduction, especially in older adults at risk for sarcopenia.
- The impact of GLP-1 RA therapy on SMM within Intensive Cardiac Rehabilitation (ICR) programs is not fully understood.
Purpose of the Study:
- To investigate the association between GLP-1 RA use and changes in SMM and fat mass (FM) in patients undergoing ICR.
- To determine if GLP-1 RA therapy affects SMM preservation during a structured cardiac rehabilitation program.
Main Methods:
- Retrospective cohort study of 468 patients in a Pritikin ICR program (2017-2024).
- Compared 67 patients on GLP-1 RAs with non-users, assessing body composition (SMM, FM) via bioelectrical impedance analysis (BIA) at baseline and program completion.
- Utilized multivariable regression models adjusted for age, sex, BMI, diabetes status, and baseline fitness (METs).
Main Results:
- Both groups showed improved cardiorespiratory fitness (METs) with ICR (p < 0.001).
- Patients on GLP-1 RAs had higher baseline BMI and body fat but similar SMM compared to non-users.
- Adjusted analyses revealed no significant difference in percent change of SMM (β = 0.62%, p = 0.326) or FM (β = 3.01%, p = 0.204) between GLP-1 RA users and non-users.
Conclusions:
- GLP-1 RA use during ICR was not associated with significantly different skeletal muscle mass changes.
- Findings support the safe integration of GLP-1 based pharmacotherapy with structured exercise programs like ICR.
- This suggests GLP-1 RAs can be used alongside cardiac rehabilitation without compromising muscle mass.
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