Fitness Myth #7: “Cardio Kills Your Gains”

🏃‍♂️ Fitness Myth #7: “Cardio Kills Your Gains”

📖 Article (~370 words)

Some gym bros treat cardio like it’s the boogeyman hiding behind the treadmill. They’ll tell you: “Bro, if you jog, your muscles will pack their bags and leave.” Relax. Your biceps aren’t calling an Uber because you went for a 20-minute run.

Here’s the truth: cardio does not destroy muscle. In fact, smart cardio can make your lifting better. The problem comes when people overdo it — running marathons while eating like a bird. That’s not cardio killing your gains, that’s poor programming and a calorie deficit that’s too big.

Let’s break it down. Cardio improves endurance and strengthens your heart and lungs. This helps you recover faster between sets and train harder overall. If your heart can’t keep up, good luck surviving high-rep squats. On the flip side, excessive cardio without enough nutrition can interfere with recovery. But that’s about balance, not doom.

Research shows that mixing strength training with moderate cardio leads to the best overall fitness. It keeps your body healthy, your joints moving well, and your body fat in check. The myth started because elite marathoners are often thin, while elite bodybuilders are massive. But those are extremes — not the average person.

If cardio killed gains, every basketball player would look like a string bean. LeBron does cardio every night — and that man is built like a tank.

So here’s the deal: cardio won’t erase your muscles. What erases your muscles is never lifting, under-eating, and spending all your time on the StairMaster while ignoring weights. Cardio + lifting + eating enough = strong, fit, and healthy.

Takeaway: Cardio doesn’t kill gains. Poor balance does.

🗂 Vocabulary

Cardio – exercise that raises your heart rate, like running or biking.
Example: He does cardio three times a week.
Student example: ____________

Muscle – tissue in your body that makes you strong.
Example: Training builds muscle.
Student example: ____________

Programming – the way workouts are planned.
Example: Good programming mixes lifting and cardio.
Student example: ____________

Calorie deficit – eating fewer calories than you burn.
Example: A big calorie deficit can reduce muscle.
Student example: ____________

Endurance – the ability to keep going for a long time.
Example: Running improves endurance.
Student example: ____________

Heart – organ that pumps blood.
Example: Cardio makes your heart stronger.
Student example: ____________

Lungs – organs that help you breathe.
Example: Cardio strengthens the lungs.
Student example: ____________

Nutrition – the food your body needs for health.
Example: Good nutrition supports recovery.
Student example: ____________

Recovery – how the body heals after training.
Example: Sleep is key for recovery.
Student example: ____________

Balance – the right mix of things.
Example: Balance between lifting and cardio gives best results.
Student example: ____________

📝 Exercises

Comprehension

Why do some people think cardio kills gains?
What really causes muscle loss in this context?
How does cardio help lifting performance?
What myth comes from comparing marathoners and bodybuilders?
What is the main takeaway of this article?

Multiple Choice

What does cardio improve?

a) Endurance b) Shoe size c) Hair growth d) Netflix skills

What causes muscle loss?

a) Overeating b) Big calorie deficit c) Drinking water d) Stretching only

Which organ does cardio strengthen?

a) Heart b) Stomach c) Kidneys d) Skin

Why do marathoners look different from bodybuilders?

a) Different sports b) Same training c) No nutrition d) Balance issues

What keeps both lifting and cardio effective?

a) Balance b) Avoidance c) Luck d) Guesswork

Fill in the Blank

Cardio raises your ______ rate.
Lifting builds ______ tissue.
Good workout ______ mixes strength and cardio.
Running improves ______.
Proper ______ keeps you healthy and strong.

True/False

Cardio automatically destroys muscle.
Endurance helps you recover faster between sets.
Too much cardio without enough food can hurt recovery.
Balance is key to fitness.
Basketball players prove cardio and strength can mix.

Discussion

Do you prefer cardio, lifting, or both? Why?
How much cardio do you think is enough each week?
Can you give an example of balance in your own training?
Why do you think people are afraid of cardio?
How could cardio help someone who only lifts?