GLP-1 medications, when used appropriately, have the power to reshape metabolic health, helping to regulate several key bodily functions and often leading to meaningful weight loss. Yet true transformation requires more than a prescription, according to experts well-versed in the treatment.
To build a resilient, lasting foundation of health, it’s crucial to pair GLP-1 usage with intentional lifestyle practices, including consistent resistance training to protect and even increase the lean muscle mass that is essential for longevity.
“GLP-1s are probably the next great evolution of what pharmaceutical research can actually contribute to the wellness of individuals,” says Jim LaValle, RPh, CCN, chief science officer for Life Time. “GLP-1s can help us regulate glucose, insulin, and glucagon to provide a bridge to getting metabolism back in individuals who are struggling or stuck. However, I’ve seen a lot of people overdoing them or not understanding how to effectively use the drug. The more you can adopt a supportive lifestyle around that GLP-1, the healthier you’ll be — and strength training is key to that to help keep and build your muscle mass.” (Learn more: “GLP-1s and Lasting Health.”)
For many who go on a GLP-1, weight loss is one of the main goals. But losing weight too fast and in the absence of supportive exercise can further damage your metabolism, according to Michael Czerniakowski, Dynamic Personal Trainer and metabolic lead at Life Time in Frisco, Texas.
“Rapid weight loss without a strength stimulus is one of the most efficient ways to wreck your metabolism,” explains Czerniakowski, a metabolic specialist who works extensively with GLP-1 patients. “Your body doesn’t care how it’s losing weight. The medication suppresses your appetite, your body sees calories dropping, and it reads the situation as a famine. And in that state, muscle is a liability.
“Muscle is expensive to maintain as it requires fuel,” he continues. “If you’re not using it, your body will gladly break it down for energy and dial your resting metabolic rate down to match, meaning you’re burning fewer calories at rest. That means your metabolism can end up worse than when you started the medication.”
Why Muscle Mass Is Important for Health
While many people think of muscle as aesthetic or purely for strength, it’s one of the most important indicators of health, longevity, and quality of life. Everything we do requires muscle. It also supports many functions in the body, including managing blood sugar, supporting joints, controlling body fat, contributing to bone health, and more. (Learn more: “What Is Skeletal Muscle— and How Does It Affect Overall Health?”)
“When we lose muscle, we’re shrinking the system that protects us from metabolic disease,” says Czerniakowski. “A person with more muscle has more mitochondrial density, better insulin signaling, and a more resilient metabolism as it preserves your resting energy expenditure. If you lose muscle, you’re not just losing tone; you’re shrinking the system that protects you from metabolic disease.”
Muscle is also one of the most significant influences in how our bodies age.
“Strength, balance, bone density, the ability to get off the floor, the ability to recover from a fall, and the ability to live independently well into your later years — all of it traces back to lean mass,” says Czerniakowski. “GLP-1 medication is a short-to-medium-term intervention. Muscle is what you carry with you for the next 40 years. If you spend a year on a GLP-1 and come out the other side with less muscle than you started with, you didn’t get healthier. Your body became smaller at the cost of your future self.”
3 Tips for Exercising and Building Muscle on a GLP-1
Exercise is critical for health, especially for those on a GLP-1, with weightlifting being a pivotal part of that plan. But for many, using GLP-1 drugs may be the first tool for prioritizing foundational healthy habits. If you’re just starting, Czerniakowski and LaValle offer their guidance.
1. Prioritize strength training.
Strength training acts as a signal to your body to hold onto muscle. When paired with adequate protein intake, it helps ensure the weight you’re losing is fat, not muscle.
“A lot of people think cardio is enough and don’t prioritize strength training,” says Czerniakowski. “While cardio is essential for cardiovascular and mitochondrial health, it does not send the signal to the body to preserve muscle the way loaded resistance training does. You need both. And if I had to pick just one for someone on a GLP-1, it would be strength training.”
2. Don’t wait to get started.
When you’re starting a new medication, you might feel tempted to wait to add in exercise until you feel more comfortable with the dosage, but Czerniakowski stresses the importance of starting to strength train as soon as possible.
“Start now,” he urges. “Not when you’ve lost some weight first. Not when you feel more confident. Not when you’ve researched the perfect program. Start showing up consistently now to build a habit that can carry you toward better health. You want to look back a year later and realize the medication wasn’t the thing that changed your life. The training habit you built during the medication use was the thing that changed your life. The medication was just what made it possible to start.”
3. Partner with a fitness professional.
Working with a fitness professional to develop a personalized workout plan can be a great way to receive guidance and hold yourself accountable.
“I would encourage anyone on a GLP-1 to work with a Dynamic Personal Trainer to develop a plan,” says LaValle. “Formally working with a professional takes the guesswork out of what you’re doing during your workouts and can ensure you’re on a path to building and maintaining muscle.”
Czerniakowski also recommends finding a trainer or coach who is experienced in working with those on a GLP-1. “When on a GLP-1, your appetite and energy can fluctuate based on how the drug is interacting with your metabolism, gut, and brain,” he explains. “An experienced trainer can change how your workout sessions are programmed based on your individual needs so you can keep training consistently.”
Setting Up for Success Post GLP-1
Many people who are prescribed a GLP-1 aren’t thinking about what will happen when they come off the medication — they’re more focused on their weight loss in the present moment. But instead of looking at it as a “quick fix,” experts stress the importance of viewing the medication as just one shorter-term tool in the bigger picture of your health.
“Many are focused on the weight loss that’s happening right now, but the key is to use the medication as a tool to improve your body composition,” says Czerniakowski.
“When you taper or stop the medication, your appetite returns, often more aggressively than before, and you are stepping back into the real world with whatever body composition you built during the medication window,” he says. “If your weight loss was mostly fat and you preserved or added muscle, your metabolism is likely intact, your strength is built, your habits are in place, and you can manage your weight with foundational habits like prioritizing protein, movement, and sleep. If your body is just a smaller version of your old body with less muscle and you haven’t formed the necessary lifestyle habits, you have no infrastructure to hold the results.”
