Are GLP-1s Sabotaging Your Strength? What This MD Wants You To Know
GLP-1 medications like Ozempic and Wegovy dominate headlines and social media feeds, celebrated for dramatic weight loss results. But here's what most people don't realize: losing weight on these drugs without the right strategy could actually harm your metabolic health.
The real measure of success isn't the number dropping on your scale. It's whether you're protecting your muscle mass.
Rocío Salas-Whalen, M.D., a board-certified endocrinologist and obesity medicine specialist, has spent over 15 years at the forefront of GLP-1 therapy. As one of the earliest adopters of these medications in the United States, she's witnessed both the transformative potential and the common pitfalls firsthand. She's also the author of the upcoming book Weightless, a comprehensive guide to navigating the new era of GLP-1 medications.
On the mindbodygreen podcast, Salas-Whalen shared her proven framework for achieving lasting metabolic health with GLP-1s, and it goes far beyond simply taking a medication.
Body composition matters more than weight
Ask Salas-Whalen to define real metabolic health, and she’ll give you three markers: high skeletal muscle mass, low body fat percentage, and low visceral fat. Notice what’s not on the list? Weight.
After years of analyzing body composition on every patient, she’s made one thing abundantly clear: “It is more dangerous to your health not to have muscle mass than to have excess body fat.” This reframes the entire weight-loss narrative.
She also describes two distinct body composition profiles she sees in her practice. The "C-shape" profile shows high weight, low muscle mass, and high body fat. The "D-shape" profile, by contrast, shows muscle mass exceeding both body weight and body fat measurements. The latter represents optimal metabolic health, even if the scale reads higher than you'd expect.
This is why the "skinny fat" phenomenon is so concerning. Someone might appear slim on the outside while carrying dangerous levels of visceral fat and critically low muscle mass. Meanwhile, someone with more visible body fat but substantial muscle underneath is actually in better metabolic shape.
"Whenever someone is starting on a weight loss journey, either GLP-1 or not, they need to know their body composition to follow muscle mass," Salas-Whalen advises.
It is more dangerous to your health not to have muscle mass than to have excess body fat.
The GPS framework
If your doctor prescribes a GLP-1 medication but doesn't discuss muscle preservation, protein intake, or strength training, Salas-Whalen considers that a red flag. She's developed what she calls the GPS framework: GLP-1, protein, and strength training. All three components are non-negotiable.
"The safety and efficacy of a GLP-1 is going to be directly proportional to the expertise of who's giving you this medication," she notes. This isn't a supplement you can pick up and figure out on your own.
Here's what the framework looks like in practice:
Protein intake:
Salas-Whalen recommends one gram of protein per pound of ideal body weight. For most women in midlife, that translates to around 100 grams daily to maintain muscle, or 120 grams to build it. Men typically need 140 grams for maintenance and 160 grams for muscle growth.
Strength training:
Start with two days per week, splitting between upper and lower body. As you build strength, gradually increase frequency and intensity. Salas-Whalen strongly recommends working with an in-person trainer initially to prevent injury, which can derail progress significantly.
The beauty of this approach? Salas-Whalen has seen patients actually gain muscle while losing body fat on GLP-1s when they follow the GPS framework. "It's like the holy grail," she says.
The mindset shift for success
Most patients come to Salas-Whalen focused on external goals: fitting into a certain dress size, reaching a specific number on the scale, or looking a particular way.
Halfway through treatment, something shifts. "It flips. It becomes an internal gain, not an external gain," she explains. Once patients start feeling strong, seeing their muscle mass increase, and accomplishing physical feats they couldn't before, the external goals fade into the background.
One elderly patient told her about nearly falling but catching herself because her core held strong. These moments of functional strength become far more meaningful than any clothing size.
This shift happens because GLP-1s remove the constant pressure of weight loss from exercise. "If you start exercising for health, for muscle, it becomes easier," Salas-Whalen notes. You're no longer dragging yourself to the gym to burn calories. You're going to build strength, and the medication handles the weight management.
But there’s a critical nuance
GLP-1s can’t compensate for poor lifestyle habits. When someone takes these medications while eating mostly processed foods, getting too little protein, or avoiding exercise (especially strength training), the body doesn’t just lose fat; it accelerates muscle loss.
That combination increases the risk of sarcopenic obesity, a state marked by low muscle mass, impaired metabolic function, and a slower resting metabolism. And without supportive habits, side effects like nausea, constipation, and fatigue often become more pronounced.
The takeaway
GLP-1 medications represent a genuine breakthrough in metabolic medicine, but only when used correctly. Salas-Whalen believes these drugs will add years to our lives and dramatically reduce chronic diseases like type 2 diabetes and obesity-related cancers in future generations. "Thanks to GLP-1s, people can reach optimal health in ways that were never possible before," she says.
But the key to unlocking that potential isn't just taking the medication. It's understanding that true metabolic health lives in your muscle mass, not on your bathroom scale. It's committing to adequate protein intake and consistent strength training from day one. And it's working with a knowledgeable provider who understands that GLP-1 therapy is a medical intervention requiring proper supervision and comprehensive lifestyle support.