Mens Health

GLP-1 and Athletic Performance in Men: What You Need to Know

If you're a man considering GLP-1 medication or already using it, you might be wondering how it affects your workouts, strength, and overall athletic performance. It's a question we hear often at Ozari Health, and it's an important one—especially if staying active is a priority in your life.

The good news? With the right approach, GLP-1 medications like semaglutide and tirzepatide can support your health goals without compromising your fitness. Let's explore what the research tells us and how to optimize your athletic performance while using these medications.

Understanding GLP-1 Medications and How They Work

GLP-1 receptor agonists work by mimicking a natural hormone in your body that regulates blood sugar and appetite. These medications slow gastric emptying, reduce hunger signals, and help you feel satisfied with smaller portions.

For men, this can mean significant weight loss—but that weight loss needs to be managed carefully to preserve muscle mass and maintain the strength and endurance you've worked hard to build.

The Impact on Muscle Mass: What Men Need to Know

One of the most common concerns among active men is muscle loss. When you lose weight rapidly, your body doesn't just burn fat—it can also break down muscle tissue for energy.

Research shows that people using GLP-1 medications typically lose about 25-40% of their total weight from lean body mass, which includes muscle. For men, who naturally carry more muscle mass than women, this can feel particularly concerning.

Why Muscle Preservation Matters

Muscle isn't just about appearance or strength. It's metabolically active tissue that helps you:

The key is being proactive about protecting your muscle while you lose fat.

Strategies to Maintain Athletic Performance on GLP-1s

Prioritize Protein Intake

This is non-negotiable for men who want to preserve muscle mass. While GLP-1 medications reduce your appetite, you need to make sure you're getting adequate protein.

Aim for at least 0.7 to 1 gram of protein per pound of your goal body weight. For a man targeting 180 pounds, that's 125-180 grams daily. Spread this across your meals, and consider timing protein intake around your workouts for optimal muscle protein synthesis.

Incorporate Resistance Training

Cardiovascular exercise is great for heart health, but resistance training is essential for maintaining muscle mass during weight loss. Studies consistently show that strength training signals your body to preserve muscle even in a caloric deficit.

Focus on compound movements like squats, deadlifts, presses, and rows. Train each major muscle group at least twice per week with progressive overload—gradually increasing weight, reps, or sets over time.

Don't Cut Calories Too Aggressively

GLP-1 medications naturally reduce your appetite, which is helpful—but eating too little can backfire. Extremely low calorie intake signals your body to conserve energy by breaking down muscle tissue.

Work with your healthcare provider to find a caloric intake that supports steady, sustainable weight loss of 1-2 pounds per week while providing enough fuel for your workouts.

Energy Levels and Exercise Performance

Some men report feeling less energetic during the first few weeks of GLP-1 therapy, especially during workouts. This is typically temporary as your body adjusts to the medication and new eating patterns.

Tips for Maintaining Workout Energy

Testosterone and Metabolic Benefits

Here's some encouraging news specifically for men: losing excess body fat through GLP-1 therapy can actually improve testosterone levels. Excess adipose tissue, especially visceral fat around the abdomen, increases aromatase activity—an enzyme that converts testosterone to estrogen.

As you lose weight, many men experience improved testosterone-to-estrogen ratios, which can enhance energy, muscle building capacity, libido, and overall vitality. This is one area where metabolic health and athletic performance intersect beautifully.

Real-World Athletic Performance: What to Expect

Most men find that after an initial adjustment period of 4-6 weeks, their athletic performance stabilizes or even improves—particularly in activities where carrying less body weight is advantageous, like running, cycling, or basketball.

Absolute strength in heavy lifts might plateau temporarily, but this is often a worthwhile trade-off for improved overall health, better endurance, and reduced joint stress. Many men report feeling more athletic and capable in their bodies as they shed excess weight.

Gender Differences Worth Noting

While this article focuses on men, it's worth noting that women typically experience different body composition changes on GLP-1s. Women naturally have higher essential body fat percentages and may preserve muscle mass more effectively during weight loss. However, the core strategies—adequate protein, resistance training, and proper fueling—benefit everyone regardless of gender.

From the Ozari Care Team

Our physicians recommend tracking your body composition, not just your weight, especially if you're athletically active. Consider getting a DEXA scan or using bioelectrical impedance measurements every 8-12 weeks to ensure you're losing fat while maintaining lean mass. If you notice significant muscle loss, we can adjust your treatment plan and nutrition strategy accordingly.

At Ozari Health we offer compounded Semaglutide and Tirzepatide as low as $99/month prescribed by licensed physicians and shipped to your door. Learn more at ozarihealth.com.

Medically reviewed by the Ozari Clinical Care Team licensed physicians specializing in metabolic health and GLP-1 therapy. Last reviewed: April 25, 2026