GLP-1 agonists demonstrate favorable outcomes in promoting weight loss, with patients experiencing a decrease in both body weight and BMI. With this success, it's also essential to prioritize key aspects of patient care by integrating cardiovascular exercise and muscle-strengthening activities as recommended interventions.
Promoting health for the long game is most effective and supportive.
"PCPs [primary care physicians] should shift the focus away from the number on the scale and toward meaningful improvements in overall health," said Catherine Varney, DO, obesity medicine director, UVA Health, Charlottesville.
That comprehensive approach includes using tools such as the "5 M's" framework (meals, movement, mind, medications, and metabolic surgery). Doing so, she said, "supports more meaningful outcomes by prioritizing metabolic health, functional capacity, and quality of life rather than weight alone."
Monitoring Patient Progression
PCPs who prescribe GLP-1 receptor agonists should closely monitor patients' rate of weight loss and remain vigilant for potential adverse effects, including nutritional deficiencies, loss of lean muscle mass (with risk for sarcopenia), and reductions in bone density, said Yuval Pinto, MD, assistant professor of medicine and part of the Healthful Eating, Activity, and Weight Program at Johns Hopkins School of Medicine in Baltimore. He said that a target weight-loss rate of approximately 0.5–1 lb/wk is generally recommended and should be considered when evaluating the need for dose escalation.
Nutritional plans should be tailored to each patient's comorbidities, weight-loss speed, and activity level. For example, sodium restriction may be appropriate in patients with hypertension, limitation of simple sugars in those with diabetes, and protein adjustment in individuals with chronic kidney disease, Pinto said.
Patients engaging in regular strength training may require higher protein intake to preserve lean body mass. Exercise plans must consider physical limitations such as age, injuries, or functional capacity as well.
"PCPs should recognize the importance of a comprehensive, multidisciplinary approach to weight management," he said, and consider referral to an obesity medicine specialist, registered dietitian, and, when appropriate, a personal trainer or physical therapist.
Creating Patient-Centric Recommendations
Tandem exercise and cardio recommendations can promote well-being and can help maintain muscle mass. Pinto laid out some guidelines:
- Begin by talking about the types of physical activity they most enjoy in order to promote something that may last and long-term sustainability.
- Explain the importance of exercise in the context of their medical conditions and weight-management goals.
- Develop a structured, progressive exercise plan with clearly defined goals (e.g., interval brisk walking to improve cardiovascular outcomes and strength training to preserve lean muscle mass).
- Encourage physical activity within the patient's functional limitations. For patients who are frail or unable to perform traditional resistance training, recommend alternative exercises such as sit-to-stand movements or resistance band training.
- Provide ongoing follow-up and troubleshoot barriers when goals are not achieved. (For example, suggest alternatives such as under-desk walking devices during periods of inclement weather or home-based resistance equipment for patients unable to access a gym.)
- Refer patients to physical therapy when appropriate, providing specific and goal-oriented instructions to guide therapy.
Additionally, Varney emphasized the importance of understanding each patient's individual situation.
"Many face limitations due to medical conditions or physical disabilities, so an effective plan incorporates activities that are both safe and achievable for them," she said. "I really reiterate to my patients that physical activity plays a critical role in cardiovascular health, mental well-being, and long-term weight maintenance."
There are effective indoor exercise options, including body weight routines, resistance bands, fitness apps, and online videos. Plus, home-centered mechanisms such as treadmill walking, chair exercises, stair climbing, dance, yoga, stretching, and balance movements with light weights can help improve strength and stability while staying at home.
Benchmarks to Chart Progress for Muscle Mass Concerns
During major weight loss, especially with GLP-1 receptor agonist therapy, PCPs can track muscle mass loss using clinical performance tests and simple body composition measurements. Pinto has outlined the following assessment tools:
- Handgrip strength: A simple, validated tool to screen for sarcopenia. Declining grip strength is an early indicator of reduced muscle function.
- Chair stand test (CST): Used to assess lower body strength and endurance; inability to perform this test or a significant increase in time required to complete it can indicate muscle atrophy. CST is recommended for older populations and for patients with a history of falls.
Also consider using these tools:
- DEXA, bone composition: Gold standard; provides a comprehensive analysis of body composition, including visceral fat and muscle mass.
- Bioelectrical impedance analysis: Recommended as a practical, first-line method for clinical practice due to its accessibility, low cost, and ease of use compared to more specialized equipment.
Nonphysical Modalities to Build Muscle
Building and sustaining lean muscle involves an evidence-based plan: adequate protein, proper recovery with restful sleep, and progressive strength training to stimulate muscle growth, according to Pinto. "It should be noted that the precise requirements for these variables — such as daily protein intake and sleep duration — are individualized and contingent upon a variety of patient-specific physiological factors," he said.