The Best and Worst Cardio for Natural Bodybuilding


A natural bodybuilder should either take it slow or go hard, but not for long. Let’s look at the types of cardio first, then we’ll get into timing and conditions.

1 Easy and Slow Cardio

It can be used a lot by natural weight lifters. When I was getting ready for my last two photoshoots, I was walking 45 minutes in the morning (empty stomach) and another 45 minutes in the afternoon (walking the dogs). Both sessions were very low intensity. Even fasting did not lead to overproduction of cortisol.

Why do it then? After all, walking doesn’t burn a lot of calories. Well, no, it’s not. But it’s still enough to help shed a few pounds over the course of my 10 week prep.

I suspect walking on an empty stomach may even help lower cortisol by reducing stress. It also increases the enzymes responsible for mobilizing fatty acids. TC Luoma wrote an article showing that fasted cardio can increase enzymes responsible for mobilizing and utilizing fat. So while it might not make a huge difference right now, it might make your body more efficient at burning fat for fuel in the future.

2 Hard As Hell Cardio

Lactic acid might decrease myostatin by increasing myogenin and follistatin – binding proteins that inhibit myostatin. Remember that the more myostatin we have, the less muscle we can build. Lactate training could help you build muscle by inhibiting myostatin. Lactate is maximized during intense efforts lasting 30 to 60 seconds.

So go all out for 30-60 seconds, then take plenty of time to recover between sets (2 or even 3 minutes). Longer rest intervals minimize adrenaline (and therefore cortisol) and also lead to better performance, leading to a stronger physiological effect.

Some options: conventional sprints, hill sprints, sled push sprints, assault bike sprints, stationary bike sprints, rowing ergometer sprints, etc.

Doing 4-8 improves cardiovascular function and boosts fat loss. You can vary the length of the sprints (30, 45, and 60 seconds are all good), the device you use, and the number of reps you do to keep things fresh and interesting. You can even combine more than one modality in a workout. For instance:

6 sets of…

  • Rower ergometer, 30 seconds of walking, no rest, then…
  • Sled push, 30 seconds, rest 2-3 minutes, repeat

The goal is to produce lactic acid and then recover almost completely between sets. I have seen it work wonders for many clients.

To learn more about this type of exercise, I recommend the book “Sprint 8” by Phil Campbell. This is what I use with my body transformation clients with great success.

Teresa E. Burton