Do You Really Need Cardio If You’re Lifting?

If you lift weights and care about building muscle, you’ve probably been told one of two things: either cardio is absolutely essential, or cardio is the enemy. Some swear by fasted morning sessions. Others claim it will kill your gains. So which is it?

The truth is somewhere in between. You don’t need cardio to get lean or to grow muscle, but it can still serve a purpose - depending on how you use it. If your main goal is hypertrophy or strength, cardio should support your lifting, not compete with it. That means knowing when to include it, how to do it, and when to leave it out.

 

You Don’t Need Cardio to Lose Fat

Let’s clear this up first: cardio doesn’t burn fat directly - a calorie deficit does. That’s the only non-negotiable factor in fat loss. You must consume fewer calories than your body uses over time. Cardio can help increase your calorie burn, but it's not essential if your diet is properly controlled.

For example, if your maintenance is 2,500 kcal/day and you eat 2,200 kcal/day, you’ll lose fat - even without a single minute of cardio. On the other hand, if you’re eating 2,800 kcal/day but running every morning, you might just be maintaining your weight or even gaining fat if that cardio doesn’t fully offset your intake.

This is why many bodybuilders and strength athletes successfully cut fat without doing structured cardio. They manage everything through precise food intake. If you enjoy walking or moving more to increase your daily energy output - great. But you don’t need to punish yourself with cardio sessions to get lean.

 

Cardio Won’t Kill Gains - If Used Properly

There’s a persistent myth in the lifting world that cardio will “eat away” your muscle. And while it’s true that excessive endurance work can interfere with recovery and hypertrophy, moderate cardio won’t sabotage your progress - and can even help in some areas.

The so-called interference effect occurs when your body receives conflicting signals: strength training tells it to build muscle and become more explosive, while long-duration endurance training tells it to become more efficient and conserve energy. If both signals are strong and frequent, they can clash. That’s why doing 5-mile runs every day does pose a risk to muscle gains, especially if you're in a calorie deficit.

But light to moderate cardio, performed 2–3 times per week, done away from your lifting sessions, does not harm muscle growth. In fact, it may enhance your training by:

• Improving cardiovascular fitness, which helps you recover between sets
• Increasing nutrient delivery and blood flow to muscles
• Boosting general work capacity, so you can handle higher training demands
• Supporting fat loss if needed without drastically lowering food intake

As long as you keep cardio low-impact, short, and separate from lifting, it becomes a tool - not a threat.

 

What Kind of Cardio Is Best for Lifters?

When strength and hypertrophy are your focus, the goal of cardio is to improve health, aid fat loss, and support recovery - not to improve endurance. That means your cardio should be joint-friendly, low stress, and easy to recover from.

Here are some of the best options:

• Incline treadmill walking - Low joint impact, elevates heart rate without burnout
• Stationary cycling - Easy on the knees, smooth intensity control
• Elliptical or stairmaster (moderate pace) - Good calorie burn with minimal impact
• Outdoor walks - Great for recovery, stress relief, and increasing step count

Avoid high-intensity intervals (HIIT) if you’re already training to failure in the gym. HIT-style lifting (like Mentzer or Dorian Yates) is already neurologically and physically demanding. Adding sprint intervals or brutal circuits on top of that can over-stress your system and reduce your lifting performance.

Rule of thumb: cardio should never take away from your recovery. If your lifts start to stall or your sessions feel flat, it’s time to reduce cardio or move it further from your lifting days.

 

When Cardio Might Be Unnecessary

There are plenty of cases where skipping cardio entirely makes sense, especially during mass-gaining or high-effort training phases. You may not need structured cardio if:

• You’re eating to grow and already lean enough
• Your daily step count is high (10k+ per day) through normal activity
• Your recovery between sessions is excellent
• You’re focused on improving one-rep maxes or neural efficiency
• Your schedule is limited, and lifting + recovery are your priorities

In these scenarios, adding cardio may do more harm than good. If you’re already progressing in the gym and your body composition is on track, don’t fix what isn’t broken. Use cardio sparingly or skip it altogether until it serves a clear purpose.

 

When Cardio Becomes Helpful

Cardio becomes a valuable tool when:

• You’re trying to lose fat while preserving food intake
• You’re in a cut and want to maintain performance in the gym
• You have poor cardiovascular conditioning and fatigue quickly
• You want to improve insulin sensitivity or overall heart health
• You’re in a sedentary lifestyle outside the gym (office work, low steps)

Even in these cases, a small amount goes a long way. Two to three 20–30 minute low-moderate sessions per week is enough to support your goals without interfering with growth.

Think of cardio as a scalpel, not a sledgehammer. Use it precisely, not aggressively.

 

Use Cardio on Your Terms - Not Because You Think You “Should”

Cardio is not essential for fat loss. It’s not required for muscle gain. But it can be a helpful tool if applied with purpose.

• If you enjoy it and recover well, include it.
• If it helps your fat loss while keeping food high, include it.
• If it burns you out, hurts your lifts, or isn’t needed - skip it.

Just remember: lifting builds the muscle. Diet controls the fat. Cardio supports both when used correctly.

Train hard, recover fully, and use cardio only when it adds value - not because fitness culture says it’s mandatory.