Cardio vs Resistance Training

Hi friends!


Back on the blog today to talk about a heavily debated topic that makes some people uncomfortable.  Should you run more or lift weights more?  Is one better than the other?  Are they both helpful?  What’s right for you?  I’ll answer all these questions for you in today’s post.


But first, story time…

Flash back to about 6 years ago.  I got married in July of 2011, and along with the happiness and bliss that came along with that, came the ‘love pounds’.  Those lovely extra pounds that come from eating out more, baking more, and working out less.  By Christmas, I was up 10 pounds and knew I had to change something.  One of my best friends was (and still is) an amazing runner.  Did all the races, and I was constantly inspired by her.  I started asking her questions about running and why she loved it and how to get started.  I dove in headfirst and signed up for a marathon.  Let me be clear, I was NOT a runner.  But I am a little crazy and when I do something, I go all in and do it big….hello marathon.  I found a simple training plan online and started following it.  I wanted to reach my goal and run the marathon but also wanted to lose some weight along the way.  And it worked.  I lost a bunch of weight and ended up loving running long distances.

Leanest I’ve ever been (or will ever be) but felt worn down, sick, and had no fat but also no muscle!

What I didn’t know, was that I was slowly destroying my metabolism and harming my hormones. I was diagnosed with hypothyroidism in 2013.  I actually went in because I thought I might be pregnant (despite many negative home tests).  I hadn’t had a period in about 6 months and was feeling EXHAUSTED all.the.time.  When I say exhausted, I mean, worn down, tired, napping every day before dinner, barely able to make it to lunch without 4 cups of coffee (and I normally didn’t ever drink more than 1!).  Running had slowly worn my body down so far that my endocrine system was having to work overtime (and coming up short, hence the hypoT) to compensate for the adrenal fatigue.



As seen from just my example, constant cardio (and doing only cardio) can really mess with your hormones, but let’s look at some of the science behind it.  Cortisol is the stress hormone that your body releases naturally.  Normally, your body’s cortisol hormones break down about 1% of muscle proteins per day.  However, when working out, it breaks down 3-5% of muscle proteins per day (source).  You can see, that over training and constant, steady cardio, will wear down your muscle proteins causing sleeplessness, elevated resting heart rate, burnout, and fatigue, which can lead to adrenal fatigue.  This is where things get a little tricky.  Your adrenal gland produces cortisol (the stress hormone that also helps regulate your metabolism) and aldosterone (which helps control blood pressure).  When you do constant, long, steady-state cardio, you cause more stress on your body, which in turn, releases more cortisol.  The constant release of cortisol can not only slow down your metabolism but also put you into adrenal fatigue, which can then affect more of your endocrine system.  You can see how it’s all connected.  When cardio, especially steady-state cardio, is the only form of working out that we do, our bodies slowly adapt and become efficient at burning calories.  You would think you would want your body to be efficient right?  Actually, the opposite is true.  We want our bodies to be inefficient at burning calories.  When you run 3 miles for the first time your body will work really hard and burn a lot of calories.  However, the more you run those 3 miles again and again, your body will adapt (because that’s what it’s built to do) and slowly, over time, burn less calories and become more efficient at keeping stored fat.  When your body is ‘efficient’ it doesn’t burn as much fat because it’s gotten used to the steady cardio and your metabolism slows down.  You want to keep your body ‘inefficient’, meaning challenging it with different workouts and building lean muscle mass.   It is crucial to find the right balance of enough cardio to strengthen our cardiovascular system but not wear down our bodies.



Resistance training is training that forces your body to work against gravity (i.e. lifting weights).  Building lean muscles mass through resistance training increases our metabolism.  Muscle burns more calories than fat.  Therefore, the more muscle you build, the more calories you will burn…and to me that means more food haha!  Resistance training will also challenge your body every time.  Meaning, you will stay ‘inefficient’ and therefore, increase your metabolism.  Building lean muscle mass also helps protect against bone health.  Women are at risk for osteoporosis because our bodies naturally start to lose bone density as we age.  One way to fight this is to be sure you’re getting enough calcium in your diet, but another great way is to lift weights!  Lifting weights provides weight-bearing stimulus to the bone, making it stronger.  “High-intensity resistance training, in contrast to traditional pharmacological and nutritional approaches for improving bone health in older adults, has the added benefit of influencing multiple risk factors for osteoporosis including improved strength and balance and increased muscle mass” (source).

More muscle definition than I’ve had before.

I personally started lifting weights more after I gave birth to my daughter.  I couldn’t run as much as I used to because my body wasn’t quite ready for that, but lifting weights didn’t put the impact on my joints that running did.  Through weight training my body composition changed and so did my strength and confidence.  I’m not as lean as I used to be while running, but I am much stronger and more confident because of it.


So does that mean, we should only do resistance training and never do cardio??  NO!  Cardiovascular exercise improves lung capacity, heart function, fat burning potential, and can even help with mental clarity.  It’s great to incorporate cardio into your routine, but make it the right kind of cardio.  Instead of running for 2 hours just because it ‘burns more calories’ focus on a HIIT (High Intensity Interval Training) workout.  It involves short periods of high intensity followed by a little rest that’s usually over in 20-30 minutes.  Great way to work cardio while still building lean muscle mass.  In fact, if you’re interested in incorporating HIIT workouts into your current routine, head over here to get my HIIT Training Program!


I hope this post gave you some insight into why we need to focus on resistance training more than cardio.  If you’ve been spinning your wheels (maybe literally in constant spin classes) doing hours upon hours of cardio and are failing to see results, let’s talk!  I’d love to help you transition into weight training more!  Please don’t hesitate to email me at


Happy Thursday!



1 Comment

  1. […] one goes right along with another blog post I did about resistance training vs cardio.  Many people (mainly women, but some men as well) think training for a marathon or running miles […]

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