November 11, 2021

At its core, CrossFit is a general fitness program and, as such, makes regular use of conditioning in its implementation. However, bench bros and wannabe-bodybuilders alike would like you to believe that such training is a detriment to your progress, specifically your muscle mass. Perhaps you have heard the myth that “cardio kills your gains.” This article will discuss why this claim is not true, and how appropriately programmed conditioning can actually lead to more muscle growth.
First, it is helpful to know what is required to effectively add muscle. Without delving too deep into the subject, muscle tissue needs both an adequate stimulus and proper nutrition to grow. Higher volume (eight reps per set or more) resistance training provides a stimulus that is conducive to muscle growth. In conjunction with physical training, the body also needs energy to facilitate the construction of additional tissue. This comes in the form of carbs, fats, and, especially, proteins. Think of proteins as the building materials, while carbs and fats are the fuel used to maintain the function of your body, including the specific process of converting protein into muscle.
When claiming that conditioning negatively affects muscle growth, many will often cite runners and, subsequently, their physique as evidence. However, this argument is fundamentally flawed because it is overly simplified. Oftentimes, a person who is a running hobbyist is likely not as invested in strength training, if at all. They may not be implementing nutrition principles, either. While a person can certainly improve their fitness with solely running (or cardio in general), it is skewed towards a specific adaptation because their training consists almost entirely of long duration conditioning. From the standpoint of general health and longevity (and for the purposes of this article, muscle building), it is ideal to incorporate both strength training and conditioning, along with nutrition. It is worth mentioning that there are plenty who participate competitively in the sport of running who have great physiques and excellent health because they also implement strength training and proper nutrition.
Contrary to popular belief, conditioning can actually contribute to improved muscle mass and strength. Many view the muscular system and cardiovascular system as entirely separate. However, they are very much intertwined. After all, the cardiovascular system is what circulates oxygenated blood to the muscular system, and the muscular system (in the form of cardiac muscle) facilitates the circulation of blood through the cardiovascular system. Increased cardiovascular capacity will increase your potential capacity for muscle growth. So do some cardio folks, it’s good for you! As long as it’s a part of a balanced and well-thought-out general fitness program. ?