Strength Training While on GLP-1’s (Part I): Protecting Your Muscle While Losing the Weight

Medications like Ozempic, Wegovy, and Mounjaro have changed the weight-loss landscape. For many people, they finally provide the appetite relief needed to make significant weight loss possible. 

That’s a big deal, especially for people who have been “following the plan” and doing what they’ve been told will work for years, with no success. But here’s what I wish was explained more clearly:

There’s a very good chance that a significant portion of your GLP-1 weight loss is muscle, along with fat, especially if you’re not consistently doing some moderate to heavy strength training. This has major impacts on your long-term results, which are even more pronounced if you’re in the 40-70 year old group.

Here’s why.

1) Weight Loss Is “Weight.” Some of That Is Muscle.

In the STEP 1 trial of semaglutide (published in the New England Journal of Medicine in 2021), participants lost about 15% of their body weight over the course of about 16 months. When researchers looked at body composition, roughly 39% of the weight lost was fat-free mass, which includes…muscle.

Sarcopenia is a loose term for the gradual muscle loss that happens with aging.  Over 40, strength training is essential for the preservation and development of muscle tissue.

Strength training helps shift the fat-to-muscle loss ratio so that:

More of the weight lost is fat

Less of the weight lost is muscle

You get those peak physiological outcomes you’re going for!

BioFit Philly offers individualized strength training that works

2) Muscle Protects Your Metabolic Rate

Lean mass is a strong component of resting metabolic rate. When you lose muscle:

• Your resting energy expenditure drops (less calories burned at rest!)
  
  

• Metabolic slow-down (Adaptive thermogenesis) can kick in as a survival mechanism to maintain energy if it’s all loss and no gain. Don’t let your body panic.
  
  As the metabolism slows, you risk re-gaining the weight when/if your course of medication stops and your appetite is no longer externally suppressed
  
  Resistance training during caloric restriction has been shown to mitigate declines in resting metabolic rate.

  Muscle is your metabolic insurance policy, and you can test your resting metabolic rate at BioFit Philly.

*It’s important to note here what I mean by “strength training.” Strength training can be a LOT of different things, but it HAS to push your muscles to the point which requires them to adapt and grow to handle the consistent, intentional stress.  It’s not little 3-5lbs weights for 15 reps once a week. It’s lifting heavy things for 5-10 reps, 2-5 times a week. It’s the same for everyone, regardless of age, gender, or previous experience.

3) Muscle Is Your Biggest Glucose Storage Tank

GLP-1 medications were developed to improve blood sugar regulation.

But did you know that about 70–80% of insulin-stimulated glucose uptake occurs in skeletal muscle?? That’s why exercise works so well for diabetics to reduce blood sugar.  As you deplete the sugars in your muscle, your muscles draw in blood sugar, reducing the amount in the bloodstream.  The more available muscle stores you have to receive those sugars, the quicker it can level out.

Less muscle = less capacity to dispose of glucose.

Building muscle through resistance training:

• Increases GLUT4 expression - more glucose transporters and better glucose storage in the muscle
  
  

• Improves insulin sensitivity - a multitude of benefits, including decreased diabetes risk, better weight management, and better liver, brain, and heart health
  
  

• You can lower your HbA1c (2-3 month blood sugar average) simply by building muscle, even if you don’t lose overall weight
  
  

GLP-1 medications help regulate appetite and improve blood sugar.

Strength training improves what your tissues do with that fuel.

Those two things work best together.

The Takeaway

If you’re using a GLP-1 and not pairing it with strength training, you’re leaving a major piece of the health equation on the table. Not to mention your enhanced outcome potentials!

If you want to make sure the weight you’re losing is mostly fat — not muscle — we should talk.

→ Schedule a strength-focused consultation below and we’ll build a plan that protects your muscle while you lose weight.