treadmill workout

Hey Alfonso,

I’m trying to build more muscle and get in better shape using free weights, but I also enjoy running. I’ve heard that too much cardio will impair your ability to build muscle. Is this true?

I lift weights for 20-30 minutes and then run at 8mph for another 30 minutes. I try to go 4-5 days a week.

Am I doing too much on the treadmill?

Thanks, Pete.

Hey Pete! You’ve asked a great question and one that I think many people are also confused about.

As most people know, I’m not a fan of extreme running or distance type training. One reason is for the reasons that you state – loss of muscle mass. In fact just the other day, I posted a picture of a sprinter and a marathoner on the Angry Trainer Fitness Facebook page  to demonstrate the differences in what happens to the human body given two opposite forms of training. Now, truth be told BOTH of the pictures were extreme – one was an Olympic sprinter and one was a man who obviously runs long distances. But even on a scaled down version of those two activities, the differences are clear.

When it comes to people who run a lot, you won’t see many holding a lot of muscle mass. Now before all the runners start jumping all over me, I’m not saying that runners aren’t toned, muscled or fit. I said they won’t carry a lot of muscle mass. One look at any marathon lineup and you’ll see that people who run a great deal aren’t muscled up. And the reason is simple. When you ask your body to run long distances or for long periods of time it adapts by shedding muscle tissue. Think about it, for one, your muscle weighs a lot, so it’s essentially baggage that your body has to carry when you run, and two, it requires calories and oxygen for fuel. It’s easy to see that with less muscle the load you’ll be carrying is lighter and the consumption of oxygen is lower. Therefore you can run easier and more efficiently. You simply don’t need pounds of muscle tissue to run far, it’s almost a liability.

Now what you’re talking about is NOT EXTREME running as it’s only 30 minutes. True, if you talk with diehard bodybuilders they’ll tell you to walk at low intensity levels and that higher intensity cardio will either burn muscle or slow the muscle building process. There may be a shred of truth to those statements but we’re talking about true bodybuilding here. In the grand scheme of things, to be optimally fit you must perform various bouts of cardiovascular exercise to make sure your heart and lungs are as fit as your biceps. So there is no right answer. You need to exercise at all levels to reap all of the benefits.

Throughout my years in training I’ve performed all sorts of cardiovascular exercise. Back in my bodybuilding days, I stayed in the tried and true 60% max heart zone for up to and hour at a time when getting ready for a show. But now it’s a whole other story. I train up to 90% max heart rate and sometimes end up gasping for breath after a sprint. And you know what? I don’t think it’s done my muscle mass any harm at all.

However what is key is that when I do perform intense sessions they’re always short, around 10-30 minutes tops. The adaptation for sprinting or explosive movements is very different. You’re training different muscle fibers, the fast twitch or type 2’s, which incidentally have a greater propensity for growth. So when I started sprinting and performing explosive plyo-metrics as part of my cardio training, I actually saw some muscle growth.

So here’s what I would say – switch it up! If the routine you describe is what you’ve been doing for a while, it’s time for something new. Why not try incorporating mini sprints in between your weight sets? Or bring a jump rope and instead of waiting 90 seconds before your next set of bench presses, jump rope for 30 seconds. Or try some jumping jacks, burpees or mountain climbers. This way you’ll get the cardio in during a down time and the entire workout will get taken up a notch. It’s a way that I train regularly and I love it. I hope that helps!

Let me know how it goes and if any of you out there would like to book a more in-depth consultation with me – just drop me a line via the How To Book button in the sidebar.

And if you have a question – please just click here. I’d love to help you!


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