First published March 7, 2018
There are things I’m objectively right about:
- U2 is and always has been a terrible band
- Kale is the beef jerky of leafy greens (and it’s awful)
- Forrest Gump will always be a delightful movie
But I’ll admit that over the years I’ve been wrong about some things, specifically when it comes to fitness. This industry grows and evolves, and I grow and evolve my opinions with it.
Now, I’m not taking a 180° turn on my viewpoints. Instead, it’s more like a pendulum that swings from one extreme to another and is now settling towards the middle near a more correct truth.
I talked shit about Cardio, and I was wrong.
My introduction to cardio came with organized sports by running laps around tracks or up and down fields to improve my cardiovascular fitness for sport.
Sidebar: from here on out I consider cardio any repetitive aerobic activity, like running, cycling, swimming, etc. in which the heart rate remains elevated and relatively stable for a period of time (3 or more minutes, although more commonly about 10-60 minutes)
By my early twenties, and for reasons I don’t recall, I would run ostensibly for fun, although I was never a great runner. Most of my runs were somewhere between 3-4 miles, or whatever I could cover in about 30 minutes, and I averaged maybe 6-10 miles a week.
In graduate school, I studied how much cardio reduces the risk for cardiovascular disease, diabetes, dyslipidemia, obesity, hypertension, and certain cancers. It turns out that with about 30 minutes of moderate intensity exercise per day (or 150 minutes per week), one can reduce those health risks by up to 40%.
Since cardiovascular disease and comorbidities cost roughly $400 billion a year, getting more people walking is massively important.
But as a meathead, I just wanted to learn more about strength training. Predictably short-sighted, I thought strength training was head and shoulders far better than cardio for any goal: wanna lose fat? Barbells. Chisel muscle? Weights. Develop Achilles-like strength, become a Super Saiyan, and fast-track your Hogwarts graduation? MOAR BARBELLS AND BUMPER PLATES.
“Cardio shmardio. I’ll show them! Strength training is vastly superior!”
“I’m pretty tired. Think I’ll go home now. “
Cardio wasn’t cutting it for me: I didn’t enjoy it; it didn’t put slabs of muscle on my frame, and it wasn’t giving me washboard abs. Cardio had become my sworn enemy: Hansel to my Zoolander.
I abandoned running like I abandoned Blink 182 when Tom, Mark, and Travis split up; cast it aside like I did my Pogs and Pokemon Cards. For the next 5+ years, I only lifted weights and did nothing more than walk my dog for cardio.
Since this is about how I was wrong, you might be on the edge of your toilet seat wondering, “What changed your mind, Andy?”
Unlike Doc Brown hitting his head on his sink and coming up with the flux capacitor, my “cardio is actually pretty great” moment was less “ah-ha” than one might hope.
Instead, it came with time.
In the fitness industry, it’s unfortunately common and super lame to jump on the cardio-bashing bandwagon, and I was no different: You kill your muscle gains with cardio, bro. Cardio is for sissies! Look at this picture of a marathon runner…would you wanna look like that?!
Then I started reading and listening to others in the industry that knew better. Coaches who train athletes and everyday people like me to be both ridiculously strong and cardiovascularly fit. They can, and should, complement each other, was the takeaway.
In my own strength training workouts, I had noticed how out-of-breath I’d become. After a set of high-rep squats, I’d be sucking wind and looking for the nearest available oxygen mask.
My workouts are typically book-ended by clients, so I have at most 60 minutes to work out, and often less. Between training and begging for air between sets, my volume of work had gone down. I was getting half of my intended workouts done in a timely manner.
The latest science was saying that low-intensity cardio was good for my muscle gains, recovery, and for my heart health.
Finally, I started listening.
After years of ignoring cardio, I went for a run one day. This was a disaster as my lungs burned and my joints figuratively exploded. I was uncoordinated and off-balance, like a baby deer learning to walk.
I lasted 20 minutes before I had to stop with aching joints and tucked tail.
Convinced however that this hell on earth would be good for me, I did it again the next week. And because the human body is incredibly adaptive, the second run sucked much less. After about 15 minutes of agony, everything suddenly felt great – my body was a well-oiled machine, striding with grace. Nothing hurt and I felt that with my current stride, I could go forever. Running bliss.
I think they call that runner’s high (lol). If I can get that feeling after 20 minutes of slow running then hell, I could do this again.
Don’t get me wrong: I still don’t enjoy running. However…
Running has vastly improved my strength training workouts.
I have no objective data: no heart rate monitors showing decreased resting heart rate. I don’t have data showing how much faster my strength training workouts are going now that I’m not sucking wind. I only have a gut feeling.
Anecdotally, my workouts are going much faster and my recovery has been roughly halved. This reduction in rest periods allows me to increase volume – more exercises, more sets, and/or more reps – while maintaining high-intensity effort.
Additionally, my recovery between workouts is better: soreness is less noticeable, allowing me to train with higher intensity frequently.
Why could this be?
I would do my Master’s in Exercise Physiology a disservice if I didn’t explain why doing some low-intensity cardio is good for strength training.
Cardio improves overall health in a variety of ways:
- It improves heart health by increasing its size, vascular perfusion, and controlling heart rate, allowing more oxygenated blood to flow more forcefully and with more volume per beat.
- Cardio increases mitochondrial density, which produces greater amounts of ATP – the fuel source muscles use to contract.
- Cardio improves vascularity, allowing for greater offloading of oxygen at the tissue level while improving metabolic waste removal.
- It improves substrate utilization: preferentially using fats during endurance events of low-to-moderate intensity.
- It aids in rest and recovery.
In essence, improved cardiovascular fitness improves general work capacity, as defined as how much “stuff” we can do in a given workout.
Dosed and scaled appropriately, steady-state cardio is relatively unobtrusive to your body, meaning that you can invest time and effort without high injury risk and aid recovery between strength training sessions.
How much and how often
I’m searching for minimum effective dose: what’s the least possible cardio training can I do to gain some benefit? The answer seems to be about 30 minutes a week of slow running. Would more confer more benefit?
Maybe, but the addition of another 30-minute run each week would be difficult to manage with my schedule. So for now, no – I don’t think additional cardio would vastly improve my strength workouts.
For you, the answer depends on your goals. If you’re searching for a minimum effective dose (which is, admittedly, a moving goalpost) then I would start with what your schedule allows: 20-60 minutes of moderate-to-vigorous (100-150 bpm) cardiovascular training per week would benefit cardiovascular health and strength training volume/recovery.
If you’re competing in an endurance event like a marathon, obviously much more: your training should revolve around aerobic exercise, with strength training being reduced to 2-4 lifts per week, depending on your endurance training schedule and recoverability.
As much as needed, and no more.
That’s a pretty good way to say it.
Maybe you’re like me and you’ve discarded cardio along your fitness journey. And maybe, like me, you’ve noticed things aren’t as easy as they once were.
Or maybe you’ve over-invested in your cardio at the expense of gaining some much-needed strength and muscle mass.
In the former case, look to add 20-60 minutes a week of cardio – something that will get your heart and breathing rate elevated.
In the latter case, cut your volume back and add more strength training. Unless you’re actively training for an endurance event, your investment in cardio is probably too high, and you could stand to devote more of your time to weight training.
In either case, you’ll likely find that you’ll not only keep getting stronger, but your weight training volume, intensity, and recovery will be vastly improved with some cardio.
CAUTION: strength training and cardiovascular training can have interfering effects, but only when one is performed excessively in favor of the other. Training your face off in both arenas is a sure-fire way to be great in neither. Carefully monitor your strength and cardio volume to optimize performance.
Wrap this up already
With cardio back in the mix, my workouts have improved. I can’t say that I love cardio, but I’ve a newfound appreciation for it. At the very least, I’ve rediscovered what it feels like to be physically challenged by something new, and how I like to push my body to embrace that challenge.
I’ll continue to court this new relationship with cardio, if not for improved performance, for my heart, which I hope will last me a long time.