Running is Killing Your Gains: Separating Facts from Myths
It's a common belief among fitness enthusiasts that cardio, especially running, is killing your gains. But is there any truth to this statement? In this comprehensive guide, we'll explore the relationship between cardio and muscle gains, debunk some common myths, and provide tips on how to balance your workouts to maximize your results. Let's dive in.
The Controversy Surrounding Cardio and Muscle Gains
A longstanding debate in the fitness world revolves around whether cardio workouts, such as running, can negatively impact muscle growth, or "gains." The belief that cardio can kill gains is primarily rooted in the idea that combining aerobic exercise and strength training can hinder muscle development. This belief is backed by various research studies, some of which support the notion that cardio can interfere with muscle gains, while others negate this idea.
The Science Behind Cardio and Muscle Gains
The conflicting evidence about the potential downsides of combining cardio and weight training arises from the fact that our bodies adapt differently to aerobic and resistance exercises. The molecular pathways responsible for these adaptations are the mTOR pathway, which is activated during resistance training, and the AMPK pathway, which is activated during aerobic exercise. When these pathways are activated simultaneously, the AMPK pathway can downregulate the mTOR pathway, inhibiting protein synthesis and muscle growth.
Studies Supporting the Idea that Cardio Can Kill Gains
Some studies have shown that performing cardio and strength training together can result in decreased strength, power, and muscular hypertrophy. For example, a review published in Sports Medicine concluded that concurrent training (aerobic and resistance training combined) is detrimental to explosive strength but not overall muscle hypertrophy or strength development. Another study published in the sport journal found that certain types of cardio exercises, such as HIIT, have little or no negative effect on resistance training-induced muscle adaptations.
Studies Negating the Idea that Cardio Can Kill Gains
On the other hand, several studies have found that adding cardio to resistance training does not inhibit strength or muscular gains. A study conducted by the American College of Sports Medicine concluded that moderate amounts of cardio can actually enhance the effects of strength training. Furthermore, research published in the Journal of Applied Physiology found that resistance training coupled with 2-3 days of cardio per week led to greater gains than strength training alone.
Why Cardio Might Inhibit Increases in Muscle Strength and Size
Interference with Molecular Pathways
As mentioned earlier, one potential reason cardio can interfere with muscle growth is that it can disrupt the molecular pathways responsible for adaptation to strength training. The activation of the AMPK pathway during aerobic exercise can downregulate the mTOR pathway, inhibiting protein synthesis and muscle growth.
Fatigue and Decreased Training Volume
Another theory is that combining cardio and resistance training can lead to fatigue and depleted energy stores, preventing individuals from lifting at the same volume or frequency as they would if they were only performing resistance training. This can result in inhibited muscle gains.
Prolonged Cardio and Protein Breakdown
Cardio sessions lasting longer than 90 minutes can significantly increase the likelihood of the body using protein as a source of energy, speeding up muscle protein breakdown. While muscle protein synthesis after exercise replenishes the protein lost, it typically only brings the muscle protein balance back to neutral rather than net positive, meaning you won't be losing muscle mass, but you won't be gaining it either.
How to Combine Cardio and Weights Without Sabotaging Your Progress
Despite the potential risks, it is possible to successfully combine cardio and weights without inhibiting your gains. Here are some tips for concurrent training:
Space Out Your Workouts
Instead of doing cardio and resistance training back-to-back in a single session, space them out by at least six hours, though 24 hours is ideal.
Prioritize Exercise Based on Your Goals
When you need to do cardio and weights in the same workout, the order matters. If increasing strength or muscle size is your priority, lift weights before completing your cardio. If your goal is muscular hypertrophy, don't perform cardio for more than 90 minutes in a single session, as this is when protein breakdown increases.
Fuel Right
Cardio can compromise your muscle growth and strength gains if you're not eating enough calories or getting the right nutrients. You'll need to increase caloric intake to provide enough energy for both workouts and consume the necessary nutrients to help repair and build muscle.
Can Fasted Cardio Inhibit Muscle Growth?
Fasted cardio, or exercising on an empty stomach, can potentially affect muscle growth. During steady-state aerobic exercise, the body prefers glycogen (stored carbohydrates) as its primary energy source. However, when glycogen levels are low, the body can break down protein (from muscle) into amino acids, which are then converted into glucose to provide energy. This can contribute to increased muscle protein breakdown.
The Takeaway
While it's true that cardio can inhibit gains in terms of muscle strength, size, and power, it's essential not to let these concerns prevent you from maintaining a well-rounded workout routine. Both cardio and resistance training are necessary for optimal health, and the benefits they provide far outweigh any potential negatives when it comes to your performance-specific goals.
In summary, if you want to avoid letting cardio kill your gains, consider the following:
- Space out your workouts
- Prioritize exercise based on your goals
- Fuel right
- Be mindful of fasted cardio
By incorporating these strategies and understanding the science behind cardio and muscle gains, you can achieve a balanced and effective fitness regime that maximizes your results.
Posted from my blog with Exxp : https://fitbrain.blog/running-is-killing-your-gains/