Written by: MATT WEIK, BS, CSCS, CPT, CSN
Certified Strength & Conditioning Specialist • Sports Nutritionist

As a certified strength coach and sports nutritionist, I work with a bunch of different clients. More and more, I’m being contacted by people taking GLP-1 medications who are looking to transform their health and longevity.

We already know that GLP-1 medications work for weight loss. The results truly speak for themselves. But some of the potential side effects are something that many GLP-1 users are looking to minimize, and that’s where strategic nutrition, supplementation, and exercise plans come into play.

Millions of people are losing weight with these injections. Blood sugar stabilizes. Appetite drops. The scale moves down.

But there’s something happening that not many people know about or have seen in the latest research. As the pounds come off, so does muscle. Bone density drops. Metabolism slows down.

According to a 2025 study published by the American Diabetes Association, up to 40% of weight loss with GLP-1 drugs may come from muscle rather than fat. That’s not a minor detail. It’s the difference between sustainable results and a frustrating rebound.

Why the rebound? It makes perfect sense when you think about it. If you lose any bit of muscle to reach your ideal weight, your metabolism can take a dive. The drop in metabolic rate, combined with the fact that when you stop GLP-1 medications, you no longer have the appetite-suppressing effects, can cause you to eat more and not burn enough calories to maintain your weight loss.

The latest research shows exactly how to protect what matters: your muscles, your bones, and your long-term metabolic health. The solution isn’t complicated, but it is specific.

In this article, we are going to dive deeper into how to mitigate some of the potential side effects from taking GLP-1 medications to help not only improve your results but also your overall health.

Disclaimer: This article is for informational purposes only and should not be used to treat or diagnose any condition. It is recommended that you speak with your doctor before starting any exercise program, making changes to your nutrition plan, or adding any new supplements into your current regimen.

• GLP-1 medications like semaglutide help people lose an average of 9.4% of their body weight and lower heart risk by up to 20%, according to the SURPASS-CVOT trial led by Lincoff and colleagues in 2023.
• Recent 2024 clinical data shows that lean mass loss accounts for 25% to 40% of total weight lost on GLP-1 drugs, which is several times faster than age-related muscle decline.
• A 2025 observational study of over 461,000 adults found that 22.4% of GLP-1 users developed nutritional deficiencies within 12 months, with vitamin D deficiency being most common at 13.6%.
• Eating at least 1.0 to 1.2 grams of protein per kilogram daily, combined with creatine supplementation, helps protect muscle and bone while taking GLP-1 medications, according to multiple clinical reviews.
• Strength training two to four times weekly helps maintain lean tissue and supports long-term metabolic health for adults using GLP-1-based treatments.

There has been a surge of new research involving GLP-1 medications over the last few years. While some of it is very impressive in terms of weight loss, some of it is concerning (especially regarding muscle mass, bone density, and metabolism).

The clinical data on GLP-1 weight loss is impressive. Weight loss with GLP-1 medications ranges from 5% to 18% in major trials.

But the scale isn’t telling the whole story. Major trials like SURPASS-CVOT and the 2023 Lincoff study showed a reduction in cardiovascular risk of up to 20%.

Here’s the part that gets less attention and is the most concerning. Muscle loss with GLP-1 medications ranges from around 25% to 39% of total weight lost. That’s not age-related decline, such as sarcopenia. That’s accelerated loss happening over months, not decades. It’s important that you focus on muscle preservation while using any sort of GLP-1 therapy.

When you lose lean muscle mass, not only does that negatively affect your strength, but it also slows your metabolism, since your muscles burn calories (even at rest) and less muscle means less energy being produced. Additionally, muscle loss can lead to mobility issues, which is a real concern as you get older.

Rapid weight loss like this is mainly due to:
1. Delayed gastric emptying
2. Dramatically reduced appetite
3. Lower caloric intake

The above is supported by detailed GLP-1 research.

A June 2025 study from the American Diabetes Association conference presented data showing that as much as 40% of the weight lost using these drugs comes from muscle mass rather than fat.

Additional research published in 2025 confirmed that rapid weight loss with GLP-1 receptor agonists can come at the cost of skeletal muscle, potentially undermining metabolic outcomes.

The good news is that the same research tells us exactly how to prevent it. For instance, diets high in dietary protein, high-quality whey protein, and supplements, combined with smart training, protect both muscles and bones during your GLP-1 journey. The use of PERFECT Sports supplements, such as DIESEL and Ultra Mag-Z, would be an ideal complement to help fast-track your results.

One thing we know is that GLP-1 medications suppress appetite.

You eat less. Calories drop. Weight comes off. But your body doesn’t distinguish between “good” and “bad” weight loss on its own.

When food intake declines, protein intake often follows suit. Your muscles need protein to maintain themselves. Without enough, they break down. At the same time, you might train less because lower calorie intake means lower energy. Reduced training accelerates muscle breakdown.

Essentially, this is a snowball effect that negatively affects many aspects of your health and life.

Then there’s what happens to your bones. As body weight decreases, mechanical loading on your skeleton decreases too. When this happens, you can experience a loss in bone mineral density. This can lead to osteoporosis. When you lose your bone mineral density, you are at a higher risk of breaks and fractures.

A 2024 study found that semaglutide increased bone resorption markers, likely due to the mechanostat theory: your skeleton adapts to reduced strain by increasing bone breakdown. Similar to the way that astronauts lose significant amounts of bone mass with only a short time spent in a zero gravity environment.

Gastrointestinal side effects make this worse. Nausea, vomiting, and digestive issues can prevent you from absorbing key nutrients, such as zinc and magnesium. These minerals are critical for both bone and muscle health.

A 2025 retrospective study of 461,382 adults found that 22.4% of GLP-1 users developed nutritional deficiencies within 12 months. Vitamin D deficiency was most common, affecting 13.6% of patients.

No matter how you look at the issues above, the solution is the same. You need to actively protect your lean muscle mass and bone density by implementing a solid nutrition and training plan. Waiting to see what happens after you start using GLP-1 medications isn’t a good strategy.

Simply taking GLP-1 medications won’t magically solve all of your weight loss issues. In fact, it can even cause some unpleasant side effects that you hadn’t planned for.

While taking GLP-1 drugs, you may experience:

• The ability to only consume smaller meals
• Faster weight loss (mainly from muscle loss)
• Slower weight loss (as your metabolism slows down due to muscle loss)
• GI changes (nausea and constipation)
• Loss of strength
• Decreased bone density
• Possible fatigue

Let’s dive a little deeper into all of this.

When it comes to your food intake, your appetite will more than likely drop extremely fast after starting GLP-1 medications. You’ll feel full sooner. Meals will end up getting smaller.

That’s the intended effect for weight management. But it brings changes you need to prepare for.

Nausea is common, especially in the first few weeks. Constipation, vomiting, or diarrhea can follow. These side effects affect not only your digestion, but also your daily comfort. For many people, these side effects will fade as the body adjusts. Unfortunately for others, they stick around.

Personally, I’ve had clients who suffered from digestive issues and discomfort for months before they finally subsided or they decided to stop using the GLP-1 drugs altogether.

While weight loss is the goal, if your metabolism slows too much due to muscle loss, you’re going to plateau. A 2024 study showed that patients using GLP-1 drugs without exercise regained an average of 6.0 kg after stopping, compared to only 2.5 kg for those who included supervised exercise.

Now, for a reality that you’ve probably seen with many of your favorite celebrities. You might notice your muscles look less defined, and overall “thinness” starts to change your appearance and body structure. Some people call this “Ozempic face.” Without enough protein or exercise, muscle mass and strength decline. Fatigue sets in. And before you know it, you’re limiting your lifestyle because you can no longer maintain it.

A 2025 study from the Journal of Clinical Endocrinology & Metabolism found that GLP-1 drugs improve certain heart function measures but don’t increase cardiorespiratory fitness.

It should also be noted that GLP-1 users who have surgery (such as bariatric surgery) tend to show better results than those who solely rely on GLP-1 medications.

Taking control of your health while using GLP-1 medications is essential for overall wellness and longevity.

Below, we’ll discuss some of the things you can do to help preserve your lean muscle mass and bone density.

1. Increase Daily Protein Intake

Higher protein intake is the single most effective way to protect muscle when using GLP-1 medications.

Research has shown that consuming twice the recommended dietary allowance (RDA) of protein during calorie restriction reduces fat-free mass loss. Protein intakes of 0.7 to 1.0 grams per pound of body weight preserved muscle better than lower intakes.

I tend to have my GLP-1 clients on the higher end of the spectrum, and recommend that they consume 1 gram of protein per pound of body weight. The added protein in their diet not only helps preserve their lean muscle but also improves their recovery from workouts and satiety throughout the day.

1. Aim for 0.7 to 1.0 grams per pound of body weight each day. For a 150-pound person, that’s between 105 and 150 grams daily. This target helps prevent sarcopenia.
2. Eat meals with at least 30 grams of high-quality protein. Eggs with Greek yogurt or chicken breast with beans make it easier to reach your intake.
3. Focus on leucine-rich foods in every meal. Dairy, fish, poultry, or PERFECT Sports DIESEL New Zealand Whey Isolate triggers the muscle growth signals your body needs while losing weight.
4. Try a protein pre-load strategy. A study published in The American Journal of Clinical Nutrition found that consuming 20 to 30 grams of protein 20 to 30 minutes before your largest meal can naturally boost GLP-1 production, decrease appetite, and increase PYY. This helps reduce total calorie intake while filling nutrient gaps from reduced food consumption.
5. Spread your protein evenly throughout the day. Dividing protein intake across breakfast, lunch, dinner, and snacks increases lean body mass retention compared to eating it all at once.
6. If you’re following a low-fat diet or dealing with nutrient deficiencies common in GLP-1 users, make sure your meals include healthy fats so your body can better absorb fat-soluble vitamins.
7. Pairing higher daily protein intake with light strength training supports metabolism and keeps bones dense during rapid fat-loss phases.

It’s important to note that not all protein supplements are created equal. On the label, they may have similar grams per serving, but that doesn’t tell the whole story of the quality.

For instance, whey protein is uniquely suited to be highly effective for those using GLP-1 medications. Incomplete proteins, like collagen protein, lack the type and level of key amino acids that can improve your results.

DIESEL New Zealand Whey Isolate contains 27 grams of pure protein in a tiny half cup (125 ml) drink that goes down smooth.

2. Creatine for Muscle & Bone Retention

Creatine is one of the most researched supplements available. Whether you’re taking GLP-1 medications or not, every single person can benefit from using creatine monohydrate. When I’m working with new clients as a certified sports nutritionist, creatine and protein powder are two supplements I often discuss that can fast-track results.

Most studies show that creatine increases muscle mass and strength, especially when combined with resistance training. For older adults, research shows lower risks of falls and fractures thanks to better bone density and stronger muscles.

The use of Essential Creatine supports muscle protein synthesis while reducing muscle tissue breakdown during weight loss. This nutrient also activates osteoblasts, the cells that help build bone.

1. Take 5 grams of creatine every day (this is considered a maintenance dose).
2. While the timing of your creatine dose isn’t as important as daily consistency, I have found you can achieve better results if you take it post-workout (such as mixing it into your post-workout protein shake).
3. To help fully saturate your muscles, start with a loading phase of 15 to 20 grams for a total of 5 to 7 days.
4. After the loading phase, a daily 5-gram maintenance dose will ensure your muscles stay saturated.
5. There is no need to cycle creatine usage.
6. Creatine monohydrate can help muscle preservation and bone mineral density, even during a caloric deficit.
7. Daily consumption can help counteract metabolic slowdown.

No negative effects on kidney or liver function have been found in healthy people using creatine. That makes it a safe choice if you want specific supplements to support your metabolism, prevent bone loss, and help with muscle preservation.

3. Electrolytes & Minerals (Zinc, Magnesium, Vitamin B6)

GLP-1 medications help reduce appetite, which aids in achieving your weight loss goals and preventing you from shifting into a caloric surplus.

Unfortunately, these GLP-1 drugs can also upset your stomach. This combination of a reduced appetite and GI issues makes it easier for you to miss out on essential minerals and vitamins that your body needs.

1. Zinc helps keep your immune system strong. A 2025 study found that GLP-1 therapy can lower zinc levels.
2. Magnesium keeps muscles working properly and supports bone density. Missing too much can lead to cramps or tiredness, which is common with reduced food intake during treatment. Additionally, magnesium helps maintain GI regularity and provides better insulin sensitivity.
3. Vitamin B6 is essential for protein metabolism and energy production. Taking a supplement may help support your metabolism while losing weight on GLP-1 drugs.
4. Diarrhea or vomiting from GLP-1 therapy puts you at risk of losing extra electrolytes like magnesium and sodium. Talk to your doctor about bloodwork to catch deficiencies early.
5. When it comes to making sure you’re getting enough zinc, magnesium, and vitamin B6, having one product that combines all three makes a huge difference. That’s why I recommend a ZMA supplement, like Ultra Mag-Z, to all my athletes and clients. Taken before bed, on an empty stomach, for the best results possible.
6. Hydrate often, especially if you’re experiencing GI side effects. Water, along with an electrolyte mix containing added magnesium, may help protect muscle function.
7. Taking digestive enzymes or prebiotic blends alongside PERFECT Sports products can boost nutrient absorption while supporting gut health.
8. Zinc and magnesium can help support mood, sleep, and muscle recovery.

Get ahead of your nutritional needs by keeping up with key vitamins and minerals. Choose high-quality supplements before problems can arise.

4. Glutamine for Gut Health & Recovery

As mentioned earlier, GLP-1 medications are tough on the digestive system. Nausea, bloating, reflux, constipation, and delayed gastric emptying are all common side effects that may either come and go or can linger for quite some time.

That matters because poor gut health directly impacts your nutrient absorption, recovery, muscle retention, and metabolism.

Glutamine is one of the most effective amino acids for protecting the gut lining and supporting immune and muscle recovery. It plays a critical role in maintaining the integrity of the intestinal barrier, which is often compromised when your calorie intake drops or digestion slows.

Research shows that glutamine helps reduce intestinal permeability, supports healthy gut bacteria, and provides better nutrient absorption. This makes it especially valuable for people using GLP-1 medications who are eating less and struggling with GI discomfort.

PERFECT Sports Essential Glutamine is a clean, pharmaceutical-grade option that helps protect the gut while supporting recovery and lean tissue.

1. Take 5 grams of glutamine once or twice daily. Many people benefit most from using it first thing in the morning and post-workout.
2. Use glutamine consistently if you experience nausea, reflux, constipation, or bloating while using GLP-1 drugs.
3. Glutamine fuels the cells that line your intestinal wall, helping repair damage and improve nutrient absorption.
4. Better nutrient absorption protects your muscle and bone density by ensuring protein, minerals, and vitamins are actually being used by the body.
5. Glutamine supports immune function, which can become compromised during aggressive calorie restriction.
6. If your workouts feel harder or recovery feels slower, glutamine can reduce muscle soreness and help preserve lean tissue during fat loss.
7. Stack glutamine with digestive enzymes or prebiotic fiber to further support gut health and minimize common GLP-1 digestive side effects.
8. If you’re dealing with chronic reflux or GERD while on GLP-1 therapy, glutamine may help calm irritation and support faster healing of the gut lining.

Protecting your gut protects everything else, including your metabolism, muscles, bones, and long-term results.

5. Strength Training Plan

Strength training is non-negotiable for patients taking GLP-1 medications. Having a solid workout plan supports muscle preservation, bone strength, and metabolism.

Interestingly enough, I’ve found that my clients who got busy and didn’t make their workouts a priority actually lost muscle during their time away from the gym.

1. Aim for 2 to 4 strength training sessions per week. This range supports muscle preservation and helps prevent bone loss during weight loss.
2. Focus on compound movements like squats, bench press (or pushups), and overhead military presses. These exercises work many muscles at once and give the best results for preserving lean mass.
3. Use light or moderate weights if you’re new or have joint issues. Steady progress counts more than heavy loads.
4. Each session should include upper- and lower-body exercises targeting major muscle groups, such as legs, back, chest, shoulders, and arms.
5. Keep each set in the 8 to 15 repetition range with good form. Push for one or two sets per exercise if you’re starting out or short on time.
6. Rest one to two minutes between sets, so you recover enough but still challenge your muscles.
7. Pair resistance workouts with some aerobic activity to support blood sugar control and improve cardiovascular health.
8. If possible, I highly recommend that you speak with a nutritionist/dietician or trainer who understands how GLP-1 works. They can make sure your routine matches your individual needs.
9. Get enough protein each day to feed growing muscle tissue. PERFECT Sports supplements can help ensure you get all the nutrients you need.
10. Stay consistent even when busy. Regular effort helps maintain metabolic rate and supports long-term weight management success for those with conditions like type 2 diabetes.
11. Track your progress every few weeks using simple home tests. Measure your waist, chest, arms, or legs with a tape measure, or see how much more you can lift over time. You can also watch the scale, but be aware that if you don’t see the number change, it could mean you’re burning fat and replacing it with lean muscle.

You now have an actionable model that you can use to help support bone density and lean mass. Just because you’re using GLP-1 therapy doesn’t mean you can skip working out.

We have been working very closely with a doctor who has many GLP-1 patients. After speaking at length, we decided to put together a PERFECT Sports GLP-1 Support Stack.

Our stack of individual products includes:

• DIESEL New Zealand Whey Protein
• Essential Creatine
• Ultra Mag-Z
• Essential Glutamine

The totality of this stack helps address all of the concerns mentioned throughout this article from the use of GLP-1 drugs and potential side effects.

To get a better understanding of how these products can help you while using GLP-1 medications, let’s unpack each product individually below and showcase some of the benefits you can experience.

1. DIESEL New Zealand Whey Protein

• Fast digestion makes it ideal for the Protein Pre-Load Strategy we mentioned earlier
• Supports muscle retention during caloric deficits
• Clean label, grass-fed, naturally high in leucine
• 1 scoop pre-meal is perfect for appetite regulation (you only need 125 ml of water)
• Only need 1 or 2 scoops per day to help reach your daily recommended protein intake
• Easy to drink, delicious, mixes perfectly, and is easy on your digestion
• 18+ flavors to satisfy your cravings

2. Essential Creatine

• Help preserve lean muscle mass
• Support muscle recovery
• Boost muscle strength
• Improve bone mineral density
• Compliments GLP-1 users on a reduced caloric intake
• 5 grams per day (any time of day) is all you need
• Unflavored creatine means you can mix it in your favorite beverage of choice
• Mixes perfectly with DIESEL or water

3. Ultra Mag-Z

• Magnesium and zinc help maintain sleep (GABA support), metabolic rate, and mood
• Magnesium citrate/bisglycinate/chelate helps counter constipation
• Zinc supports immune function and appetite regulation
• Vitamin B6 (P-5-P) supports neurotransmitters and energy stability
• Vitamins D3 and K2 help support bone density
• 3 capsules daily (preferably before bed for additional sleep benefits) is all you need

4. Essential Glutamine

• Helps maintain gut integrity during low calorie intake
• Supports recovery and immune function
• May help reduce GI discomfort
• 5 grams daily is all you need
• Unflavored glutamine means you can mix it in your favorite beverage of choice
• Mixes perfectly with DIESEL or water

GLP-1 medications can provide you with some amazing weight loss results. However, you need to be mindful and take decisive action to preserve your lean muscle mass.

The number on the scale only tells part of the story. The last thing you want is a significant portion of your weight loss to come from muscle wasting. If that happens, you’re looking at an uphill battle, as you may then begin your fight with a slow metabolism, weak muscles, and weak bones.

With the right nutrition, targeted supplements like what is offered at PERFECT Sports, and a smart training plan, you can support muscle preservation, maintain bone density, and keep your metabolism active.

PERFECT Sports offers clear guidance that uses real science to help you make safe and effective choices every step of your GLP-1 journey.

BE GREAT. EVERY DAY.

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