Are the New GLP-1 Medications Impacting Overall Muscle?
Is this statement overblown or is it warranted? As a fitness professional I attempt to continue to educate myself so that I can provide evidence-backed advice, not only when it comes to exercise that optimizes hypertrophy, but when it comes to new tools to implement body composition changes.
What we currently know from data and evidence on other types of diets, gastric bypass, GLP's, caloric consumption restriction is that each of these will cause loss of "Lean Mass" often referred to as "Fat Free Mass". Any time you restrict calories you will have some form of FFM loss. The biggest changes that occur are total body water and muscle mass as our body and muscle are both made up of a lot of water (78%+), however that isn't where the real concern potentially lies.
The real concern is that most diets that have any form of caloric restrictions, let's take bariatric protocols for example, have structured targets of protein intake and resistance exercise training (RET) to assist on preserving your "Skeletal Muscle Mass".
Skeletal Muscle Mass and Lean Mass/FFM are different. Skeletal Muscular Mass is the only muscle type that you can actively grow through exercise and nutrition. When people talk about gaining more muscle during workouts, they are simply referring to gaining Skeletal Muscle Mass by the intake of protein and resistance exercise training.
What about GLP's? Do they have protocols in place to maintain Skeletal Muscle Mass.? If so, I haven't heard of this being part of the mitigation plan as GLP-1's have been just a marketing dispensary reminding you of pain medication clinics in Florida in the early 2000's with Oxycodone. I by all means, am not saying that the same addiction, deaths, and havoc are going to occur with taking a GLP-1 Medications, but in my personal opinion, and based upon the studies that I have read, havoc to body composition is very plausible and concerning.
Some of the concerning evidence that is being reported in GLP-1's studies is weekly rapid weight loss. The weekly rapid weight loss that is occurring with the intake of these medications is sometimes 2-3x's or 5%-10% of an individual's body weight. For sustainability and preservation of Skeletal Muscle Mass, weekly gradual weight loss of 0.5%-1% of overall body weight has shown long-term success and adherence.
Some of the weight loss questions that arise from GLP-1 usage are:
1-Does this type of weight loss amplify protein and micronutrient losses?
2-What if you ever decide to stop taking the GLP's, do you regain the weight, and the medical conditions that you were attempting to prevent?
3-The other question that is arising is, what is it doing to body composition, if you go on and off GLP-1's, due to possibly adherence issues or side effects?
As I took a deeper dive into these questions, this is what I found based upon a few three evidence-based studies, including abstracts, that are available and attached to this article.
The first study is a Danish abstract that compared 77,000 individuals who discontinued GLP-1 Medications. The second is a meta-analysis study showing clinical evidence of weight gain after GLP stoppage. A third, an Oxford abstract, that summarizes the discontinuation of GLP usage versus gradual weight loss. Below is a summary of the data, the findings, and potential drawbacks.
WHAT DOES THE DATA IMPLY:
For starters, Rapid Weight Gain: Stopping the GLP medication often returned the individual to rapid weight gain due to numerous reasons:
1- Loss of Lean Mass
2- No Current RET (Resistance Exercise Program) to maintain Skeletal Muscle Mass
3- Body Composition Changes
4- Slower Basal Metabolic Rate (anytime Lean Mass or Skeletal Muscle is lost)
Secondly, Reversal of Health Benefits: those initial health benefits of cardiometabolic markers and weight loss reverted back within 1.4-1.7 years.
1- Blood pressure
2- Cholesterol
3- Fasting Glucose/Insulin
4- Triglycerides/Fat
Thirdly, no clinical oversight or behavioral support. The majority of the individuals purchasing or taking GLP-1's are private and not under oversight of a clinician.
1- The drugs are not "quick fixes", but rather long-term management tools.
2- Lack of exercise adherence. Exercise needs to be included and recommended.
3- Protein consumption and micronutrient intake also needs addressed due to Skeletal Muscle Mass changes. GLP-1's don't just quell addiction cravings, they stop them from forming in the first place. If this is the case, how to you properly maintain muscle protein synthesis without support?
4-Additional support is needed and suggested. Behavior therapy should be considered to maintain weight loss along with #3.
FINAL THOUGHTS:
IMHO (In My Humbled Opinion), I have a few questions. Would a structured Resistance Exercise Program change anything for adherence to GLP's? How about structured Protein and Micronutrient consumption? Are these not being done due to affordability and guidance that would cost extra? Would the inclusion and guidance help change the loss of Skeletal Muscle Mass and Lean Mass?
Despite these questions that I have, the studies are quite clear that without resistance exercise training, protein consumption Skeletal Muscle Mass will be lost, how much is the question and if you discontinue the GLP, what is the price you will ultimately pay to recoup what you never really lost?
When overall body composition changes in short periods of time, muscle is lost. How much is "to be determined". As we quite don't know yet, and it could vary from individual to individual based upon what I concluded in the summary.
What I do know, is that if you are reading this because you are a fitness professional working with this population of individuals, it is important that you know how to serve them.
I also know that if you are reading this because you are considering GLP-1's, medicine does not replace coaching and prescriptions does not replace community.
In the GLP era, fitness will not lose its relevance it will become indispensable.
Disclaimer: Sharing a study in NOT an endorsement. You should read the orginal research yourself and be critical.
