Buzz
Both cardiovascular exercise and strength training are essential for your fitness, a truth I’ve always been aware of but can’t seem to stop emphasizing. As someone primarily focused on strength training (specifically, a weightlifter), I once believed that heavy lifting alone was sufficient. However, incorporating more cardio into my regimen significantly enhanced my lifting performance. Who would have thought cardio could be so beneficial?
However, a common misconception exists about merging these two fitness disciplines. The so-called cardio “interference effect,” often cited by gym enthusiasts, is mistakenly believed to be scientific evidence that cardio undermines muscle growth. The logic follows that less cardio equals more muscle.
This belief is unfounded, though it stems from a few kernels of truth. Let’s explore these points and understand their actual relevance.
Effective time management is crucial
Every moment spent on cardio is a moment not spent lifting weights, such as squatting under a barbell. In this way, increasing your cardio time reduces the time available for strength training.
Runners often avoid strength training for similar reasons: they prefer spending an hour outdoors rather than in a confined gym. However, this doesn’t negate the fact that runners genuinely need to incorporate strength training, just as weightlifters must allow their cardiovascular systems to function optimally.
The solution lies in better planning. If your gym days are Monday, Wednesday, and Friday, you likely have some time on Tuesday and Thursday to dedicate to activities like cycling, cardio dance videos, or hiking. (If walking is intense enough, it qualifies.)
Even if a full cardio session isn’t feasible, you can likely carve out a few minutes daily for a brief workout or a quick HIIT session (preferably authentic HIIT, not the diluted versions, though any effort is better than none).
Adequate nutrition is essential for both goals
When building muscle, many aim to support the process by consuming enough calories to gain weight. Some weightlifters avoid cardio out of fear that it burns too many calories, potentially hindering weight gain.
The solution is straightforward: Ensure you consume sufficient calories. Your total caloric intake should balance the calories burned through daily activities and structured workouts. If your weight isn’t moving as desired, tweak your diet or exercise routine to stay on course.
Cardio might hinder muscle growth, but only in extreme cases
The kernel of truth in this myth lies in studies showing that individuals training for both strength and cardio experience slower strength gains compared to those focusing solely on strength training. You can explore a summary of some of these studies here.
However, the discussion doesn’t end there. Research also indicates that beginners can enhance their strength despite incorporating cardio, and that cycling might have less interference compared to running, if any. For those not deeply specialized in a single sport, the interference effect may be negligible.
Even where the effect exists, it’s minimal: Cardio doesn’t prevent muscle growth but may introduce a slight tradeoff. So, even if the interference effect is real and relevant to you, it’s not destroying your progress—just potentially slowing it marginally.
A practical perspective also supports this. While no one has simultaneously been a top marathoner and an elite powerlifter, achieving both would require entirely different physiques and training regimens.
Conversely, many athletes excel in both strength and endurance. Tune into the Crossfit Games for proof. It’s possible that top Crossfitters could be slightly stronger without bike sprints or faster without lifting, but their training has clearly enabled them to master both disciplines.
In fact, cardio can enhance your lifting performance
Whether the interference effect is minimal or nonexistent, avoiding cardio entirely to focus solely on weightlifting isn’t without consequences. Let’s explore what you miss out on by neglecting cardio: improved work capacity.
Engaging in cardio (or “conditioning,” a term more appealing to lifters) strengthens your heart, enlarges blood vessels, and enhances your body’s ability to deliver oxygen and nutrients to muscles while removing waste. These benefits speed up recovery between sets.
Since incorporating more cardio into my routine, I’ve noticed a significant boost in my gym performance. Previously, I needed long breaks between heavy squat sets or deadlifts, and high-rep clean and jerks left me gasping for air. This makes sense, as intense lifts demand a lot from your entire body.
Now, with regular runs and minimal rest during accessory exercises like curls, along with conditioning moves such as sandbag carries and kettlebell swings, my cardiovascular system gets a workout akin to interval training.
As a result, my workouts are more efficient. I recover faster between squat sets, breeze through circuits of presses and rows with little rest, and find high-rep sets challenging but doable. My training sessions are shorter, and I’m better prepared for back-to-back lifts in competitions. Most importantly, I’m building strength and muscle more effectively than before. Try adding some cardio—it might work wonders for you too.
