You’ve heard the benefits of high-intensity cardio for weight loss, but you’re concerned it’ll cost you hard-earned muscle. Learn the truth!
Q. I Hear People Talking About High-Intensity Cardio Constantly These Days, But I Still Know A Lot Of Guys Who Slog Away For Hours Doing Low-Intensity Work. I Just Want Whichever One That Won’t Cut Into My Gains! What Should I Do?
One of the undeniable hallmarks of bodybuilding is extreme muscularity. The other is razor-sharp conditioning. Look at pretty much everybody’s program, and you’ll see how they approach these two goals: resistance training to build mass, followed by some cardio to burn fat. Simple enough, right?
The science backs up the effectiveness of these two modalities. It’s where they mix, in “concurrent training,” that things get complicated. For instance, a study published in the Journal of Applied Physiology in 1998 found that 10 weeks of resistance training plus cardio resulted in greater fat loss than lifting weights alone. Unfortunately, in that same study, strength gains were cut in half when cardio was added to weightlifting.1 Other studies have similarly found that muscle growth is severely decreased when cardio is integrated into a program.2,3
There are a number of explanations as to why cardio blunts gains. One is that cardio adds extra volume to your training, making it difficult to recover from normal lifting.4 Other researchers maintain that the physiological adaptations that follow cardio training are the complete opposite of those which occur with lifting weights, and that cardiovascular gains are thus capable of cancelling out gains from weight training.5
Both of these scenarios imply that mass-seekers are paddling upstream when they begin trying to cut fat. So is it really impossible to maximize the positive effects of cardio, while eliminating the negative? My colleagues at the University of Tampa and I have been studying this question in recent years, and we have some good news for you: It is possible. It all depends on what type of cardio you choose, and how much of it you perform.