Does Running Kill Muscle Gains? Here’s How You Can Run and Build a Bikini or Fit Model Physique.
6 minute read
If you’ve ever wondered, “Does running kill muscle gains?” you’re not alone!
Aspiring and seasoned competitors worry that running will ruin all the hard work they put in at the gym. The good news? You can run and still build the muscle needed to improve your physique.
In this article, I will break down some of the common worries people have about combining cardio and lifting, the benefits of endurance training, and the ‘how to’ of combining running and bodybuilding to thrive as a hybrid athlete.
How Cardio Could Potentially Affect Your Gains
So, why do so many people still ask, “Does running kill muscle gains?” Much of it comes from uncertainty about how cardio and weight training interact. Let’s look at the main reasons people fear cardio will negatively affect their muscle-building progress and see how you can avoid these mistakes with a smart approach.
Time Constraints
Most people have a limited amount of time they can dedicate to working out. Adding in running or any form of cardio training takes time. If adding in cardio workouts means eliminating a significant number of lifting sessions over an extended time, this could impact long-term muscle building. Making time to fit both running into your schedule without sacrificing your lifting sessions is key!
Key Takeaway: Balancing cardio and strength sessions within your schedule ensures you don’t compromise the essential lifting volume needed for continued muscle growth.
The Interference Effect
One of the biggest worries behind the question, “Will running kill my gains?” is rooted in the concept of the interference effect. This idea comes from the fact that endurance and hypertrophy training activate different cellular pathways: lifting triggers the mTOR pathway, while endurance training activates the AMPK pathway.
Many people mistakenly believe the mTOR pathway is “turned off” when cardio “turns on” the AMPK pathway. Instead, think of them both as sliders, not on-off switches.
Research shows that while the interference effect can exist in theory, it doesn’t cause meaningful issues in practice. Unless you’re training at extreme levels with inadequate recovery, you’re unlikely to see real-life drawbacks from hybrid training when following a smart program.
Key Takeaway: When programmed intelligently—and with proper recovery—combining endurance and hypertrophy training rarely causes the theoretical “interference” many fear.
Increased Energy and Recovery Demands
Combining lifting and running means more total training volume – and more training volume means increased energy and recovery needs. If an athlete doesn’t eat to support their activity level, they WILL eventually see a decline in both their endurance and muscle gains. Eating enough calories and recovery strategies, like sleep and rest days, are crucial for success!
Key Takeaway: More training requires more fuel and rest—proper nutrition and recovery practices help you crush your cardio and lifts without sacrificing muscle building or endurance improvements.
The Benefits of Cardio for Muscle Building
Pursuing running or other endurance-based goals simply because you want to improve in those particular areas of fitness is an awesome and noble goal!
Personally, I hope that is one of the biggest reasons you’re here reading this article — because you want to be an all-around athlete and fit human. However, if you need some extra encouragement or confirmation you’re making the right choice, let’s dive into some ways endurance training can help you in your hypertrophy pursuits.
Endurance Training Improves VO2 Max
Having a higher VO2 Max means you can push harder and longer before fatigue sets in — whether you’re doing hill sprints or heavy hip thrusts. By improving your cardiovascular capacity, you can maintain a higher level of intensity during tough lifts (like leg day!), ultimately supporting greater overall training performance.
Key Takeaway: Increasing your VO₂ Max helps you sustain higher-intensity workouts, allowing you to push your limits in both endurance and strength sessions.
Endurance Training Enhances Blood Flow
Cardio encourages the formation of additional capillaries. Why is this important? Because more capillaries mean more oxygen and nutrients are delivered to your muscles, while waste products are removed more efficiently. This enhanced circulation can improve both performance and recovery, benefiting strength and endurance pursuits alike.
Key Takeaway: Better blood flow speeds up nutrient delivery and waste removal, leading to stronger workouts and faster recovery for both lifting and cardio.
Endurance Training Boosts Energy Production
Cardio increases the number of mitochondria (a.k.a. the powerhouse of the cell) within your muscles. More mitochondria means more ATP (energy) available for powering through mile repeats, Bulgarian split squats, or anything in between. This increase in cellular energy production makes it easier to sustain higher-intensity workloads for longer periods.
Key Takeaway: More mitochondria equals more energy, helping you maintain intense training efforts and potentially boosting your overall workout capacity.
Endurance Training Elevates Overall Fitness and Health
Improving endurance benefits cardiovascular, cardiorespiratory, and metabolic health. A fitter, healthier body helps you handle greater training volumes. A fitter body can recover more quickly between workouts—and even between sets! Plus, being a well-rounded athlete contributes to greater longevity in the sport, allowing you to keep chasing new goals for years to come.
Key Takeaway: A strong cardiovascular base supports higher training volumes, better recovery, and long-term athletic success—both in and out of the gym.
Rocking the Hybrid Lifestyle
Okay, it’s time to get down to how you can actually rock a hybrid athlete lifestyle.
It comes down to three main things —
Smart Programming
Fueling Properly
Prioritizing Recovery
Run Smart 🏃♀️
Choosing your runs strategically is essential! Getting the biggest bang for your buck regarding weekly miles can help ensure you see your endurance improve without burning out.
High-Intensity Runs: Include 1-2 sessions per week (such as tempo runs or 800-meter repeats) to boost speed and VO2 max.
Easy Zone 2 Runs: Slow, steady runs build your aerobic base without excessive stress.
Progress Gradually: Increase volume and intensity slowly to prevent injury and burnout.
New to Running?
Start Small: 1–2 short, easy runs or run/walks per week. These could be as short as 3-5 minutes of running.
Build Over Time: Increase running time based on recovery. Don’t feel pressure to increase every single week.
If you’re new to cardio—or returning after a long break—it’s normal to experience a short-term dip in your lifts as your body adapts to the extra volume. Don’t panic if your legs feel more dead than usual on leg day or if you temporarily can’t push the same weight. This will subside as your body adapts.
Fueling Is Everything! 🥑
Running plus lifting equals higher energy demands. Adequate nutrition is non-negotiable:
Carbohydrates: Power your runs. Up carb intake on higher output days, like long run or high-intensity workout days.
Protein: Support muscle repair and growth after lifting and cardio sessions. Generally speaking .8-1g of protein per pound of body weight is a great target to shoot for.
Healthy Fats: Sustain overall energy and hormone function.
Without proper fuel, muscle recovery slows down, and the risk of overtraining rises. Don’t shortchange your body—eat enough to meet your increased energy needs.
Prioritize Recovery 💤
Aim for 7-9 hours of quality sleep each night. Adequate rest enhances muscle repair, mental sharpness, and waste removal from the body—key factors in handling increased training stress.
Why Sleep Matters: It’s as crucial as proper nutrition for recovery. Well-rested athletes adapt better to hybrid training, making it easier to blend running and lifting without losing gains.
Bringing It All Together
By running smart, fueling adequately, and prioritizing recovery, you can enjoy the best of both worlds – building muscle and endurance! Remember, consistency is key. Your body will adapt over time, and soon, you’ll be crushing PRs in the weight room and logging new personal bests on your runs.
Embrace Being an Athlete
The bottom line? You don’t have to choose between running and being a Bikini or Fit Model competitor. Embrace your athleticism and enjoy your fitness!
When you strike the right balance, the answer to ‘Does running kill muscle gains?’ is a big NOPE! In reality, with smart planning and by eating enough, running (or any cardio) can make you a stronger, fitter, more badass athlete — both on the bodybuilding stage and off.
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