GLP-1 agonists are touted as a miracle drug of our generation, and approximately 12 percent of American adults have used them thus far. As beneficial as they may be to aid weight loss, manage diabetes, and even curb certain addictions, they’re not without undesired side effects. One inconvenient truth that doesn’t get a ton of airtime is the fact that muscle loss is highly likely while taking these medications… which could have some unfortunate consequences.
That said, is muscle loss inevitable while taking GLP-1 meds, and what can you do to combat it? We asked a weight loss physician and a certified personal trainer for the scoop.
Do GLP-1 Medications Cause Muscle Loss?
First things first, it’s worth noting that GLP-1 agonists don’t directly cause muscle loss. “Instead, muscle loss can occur indirectly due to decreased protein intake, overall calorie restriction resulting from appetite suppression, and lack of weight-bearing exercises,” says Elizabeth Sharp, MD, DABOM, IFMCP, a board-certified internal medicine and obesity medicine physician and the founder and medical director at Health Meets Wellness in NYC. “Muscle loss typically occurs during any significant weight loss, with or without GLP-1 medications.”
However, muscle loss is highly common in people on GLP-1s—and research shows that it may actually be more pronounced in people taking GLP-1 meds versus other methods for weight loss.
Per a 2024 article in The Lancet Diabetes & Endocrinology, studies suggest that muscle loss on GLP-1s ranges from 25 to 39 percent of total weight loss over 36 to 72 weeks. In contrast, non-Rx caloric restriction studies have shown only a 10 to 30 percent reduction in fat-free mass. The authors also add that the decline in muscle mass on GLP-1s is several times greater than what’s expected from natural age-related muscle loss.
Why Muscle Mass Is So Important
Maintaining or increasing muscle mass is crucial—especially as we grow older, as well as to promote optimal weight loss outcomes (whether or not you’re on GLP-1 meds). “Preserving muscle mass is vital for overall strength, mobility, and longevity,” says Dr. Sharp. “Additionally, adequate muscle mass helps maintain bone density, reducing the risk of osteoporosis, which is particularly important for aging women.” She adds that rebuilding lost skeletal muscle becomes more challenging over time, which underscores the importance of building and preserving your muscle mass as early as possible.
According to a 2024 issue of JAMA, excessive muscle loss while losing weight—which GLP-1s appear to instigate—is also associated with an increased risk of disability, hip fracture, and mortality in older populations.
How to Preserve Muscle Mass When Taking GLP-1 Medications
Although some muscle loss is expected when taking GLP-1s, it’s possible to keep it to a minimum—namely by heeding the expert-approved tips below.
1. Amp Up Your Protein Intake
Protein is the name of the game not only to build and maintain muscle but also to support weight loss, body composition, and greater health. In her practice, Dr. Sharp and her team of dietitians typically advise aiming for 35 percent of daily macronutrient intake to come from protein, which can help maintain skeletal muscle mass while losing weight. Some experts also cite 60 grams of protein daily as the minimum you need to preserve muscle, yet the exact number will depend on a range of personalized factors.
To reach and track your protein goals, it can help to use a food diary or app to help you calculate your macros. Moreover, if you find it difficult to chow down on lots of protein daily, a protein powder like HUM’s Core Strength is an easy and convenient way to supplement your diet.
2. Keep Cardio to a Minimum
While cardio is great for cardiovascular health and a popular form of exercise to burn calories, too much of it—especially without resistance training—could actually backfire, says
Marshall Weber, CPT, owner of Jack City Fitness in Boise, Idaho. “Doing too much cardio can leave you with muscle loss, and that is without the GLP-1 even present,” he warns. As such, he recommends that people on GLP-1 meds limit cardio to only 2 to 3 sessions per week.
3. Strength Train
To prevent muscle loss while on GLP-1 medications, consuming enough protein and dialing up your strength training makes for a perfect match. “I recommend weight-bearing or resistance exercises at least 3 to 4 times per week to maintain muscle mass and preserve strength, which is key for longevity,” says Dr. Sharp.
Weber agrees, saying 3 to 4 strength training sessions a week is key to minimizing muscle loss—and perhaps even building muscle while taking GLP-1 meds. “To train your body more effectively and allow it to develop helpful muscles, try using more compound movements in your strength training,” he advises. (Compound exercises involve using several muscle groups at once, and include the likes of push-ups, squats, chin-ups, and dips.)
4. Rest Well
As important as it is to do weight-bearing exercises to combat muscle loss, on the other side of the coin, rest is equally as crucial. “Long gone are the days where getting your 5 [strength] sessions in a week is ethical or helpful,” Weber shares. “The body does some of its most important work while we rest, and even while we sleep. So keep hitting the weights hard, but don’t forget to hit the pillow even harder.”
In case you have trouble falling or staying asleep, sleep supplements like HUM’s Beauty zzZz and Mighty Night can help promote a better night’s rest.
5. Enlist Professional Help
As simple as it may be to take your GLP-1 meds each week, navigating the full process can be challenging. Whether you’re concerned about muscle loss, creating a meal plan or a workout plan, or combating other GLP-1 side effects like nausea, having a professional team to lead the way can ensure that you healthily and sustainably succeed with your GLP-1 journey.
For instance, Dr. Sharp’s team tracks important metrics like body composition—aiming for only about 10 percent of weight loss to be from skeletal muscle mass—and adjusts personalized protocols based on this goal and patient input. “Our dietitians create personalized meal plans that ensure adequate protein intake in a way that’s sustainable based on our patients’ preferences and lifestyle,” she shares. “I also provide exercise programs for all my patients through our practice app.” With expert-led guidance and interventions, those on GLP-1 medications can help ensure lower rates of muscle loss and ensure they’re getting the nutrients and movement they need.
The Takeaway
In an ideal world, weight loss would come straight from fat… but that isn’t the case. Muscle loss doesn’t get enough attention in the GLP-1 conversation, but it should be considered and addressed for anyone taking these new weight-loss drugs.
Although some muscle loss is expected no matter if you’re taking GLP-1 meds or losing significant amounts of weight with other methods, it’s within your power to keep it to a minimum. The secret? “You really have to be mindful of your protein intake, along with balancing a consistent weight training regimen to encourage the body to stay developing in the ways that are healthy,” says Weber.
Dr. Sharp is also optimistic about preserving skeletal muscle when taking GLP-1 medications, though it’ll take a concerted effort to follow the tips above. “It’s definitely possible to maintain more muscle mass while losing weight with GLP-1 medications,” she says, with the caveat that your best chances of doing so will be when you work with a healthcare team that specializes in GLP-1s and weight loss.
GLP-1 and Muscle Loss FAQs
Does GLP-1 make you lose muscle?
GLP-1 medications don’t directly cause muscle loss. However, they can indirectly lead to muscle loss due to lower protein intake, caloric restriction due to a low appetite, and not strength training enough. “Generally, about 25 percent of the total weight lost [on GLP-1s] is from skeletal muscle,” says Dr. Sharp.
Can you gain muscle while on GLP-1?
Preserving muscle on GLP-1s can be challenging, and building muscle will be even more so—though not entirely impossible. According to Weber, muscle gains are typically stunted due to a lack of dietary protein. “While it is possible to gain muscle while you are taking a GLP-1 medication, it is going to be even harder due to appetite suppression that comes with taking these kinds of medications,” he explains. “Hitting the caloric surplus may feel like an uphill battle, and can even leave you feeling really uncomfortable being that full on the medication.”
How do you prevent muscle loss on semaglutide?
Getting enough protein daily and strength training 3 to 4 times a week can help keep muscle loss at bay when taking semaglutide and other GLP-1 medications.
Should I lift weights on Ozempic?
Yes, weightlifting 3 to 4 times per week is a good target to preserve muscle mass (not to mention healthy aging benchmarks) while on Ozempic and other GLP-1 drugs.
