Why Slow Eccentric Phases Won't Build a Lot of Muscle: A Deep Dive into Muscle Physiology

Article Summary:

In this article based on the Chris and Paul Show podcast episode, Paul Carter and Chris Beardsley break down the common misconception that slow eccentric movements (lowering the weight) are a secret key to building more muscle. Instead, the experts highlight that eccentric or negative resistance contributes very little to overall muscle growth compared to concentric movements (lifting the weight).

1. Concentric Resistance Builds 90% of Muscle  
The majority of muscle growth comes from concentric resistance exercises, which engage fast-twitch muscle fibers responsible for hypertrophy. Products like the MAXPRO, which focuses on concentric resistance, are ideal for achieving optimal muscle growth. This type of training contributes about 90% to muscle building, making it the most important phase of any workout.

2. Eccentric Movements Only Contribute 10% of Muscle Growth
Eccentric, or negative resistance, which occurs during the lowering phase, does help build muscle, but it only accounts for about 10% of total muscle growth. This is due to the limits on muscle fiber lengthening and reduced muscle activation during eccentrics. Incredibly, similar results can be achieved through static stretching, which is a safer and less fatiguing method for stimulating muscle fibers in a lengthened position.

3. Efficient Muscle Building
For maximum hypertrophy, you only need to perform 5 to 8 reps at maximum intensity for 3 sets, 2 to 3 times per week. This means you don’t need long or complicated workouts to see results. Again, this makes the MAXPRO unique with its focus on concentric resistance, as it offers an efficient, time-saving solution that allows you to maximize your muscle growth in less time.

This article emphasizes that focusing on concentric resistance training with efficient tools like MAXPRO is the key to effective muscle building. By doing just a few intense reps per week, you can maximize muscle growth while saving time and effort.

Continue to read the full article:

When it comes to building muscle, one popular idea that continues circulating in the fitness world is that slowing down the eccentric phase (the lowering portion of a movement) will lead to significant muscle growth. This belief has been spread by many fitness influencers, leading many gym-goers to focus heavily on slow-lowering movements during their strength training routines. But is it really effective?

In a recent episode of 'The Chris and Paul Show', Paul Carter and Chris Beardsley, two experts in muscle physiology and biomechanics, take a critical look at this common misconception. Spoiler alert: slowing down your eccentric movements won’t lead to dramatic muscle gains. In fact, it's not the muscle-building hack many people believe it to be.

What Is Eccentric Training?

Before we get into why slow eccentrics won’t build a lot of muscle, let’s first define what eccentric training is. In strength training, there are two main phases to any lift:

- Concentric phase: The lifting phase where muscles shorten (think of raising a dumbbell in a bicep curl).

- Eccentric phase: The lowering phase where muscles lengthen (as you lower the dumbbell back down).

The idea behind focusing on slow eccentrics is that by prolonging this phase, you can increase time under tension and, therefore, muscle growth. However, while eccentric contractions do have their place in training, they won’t provide the massive gains some claim.

Why Slow Eccentrics Won’t Build Extra Muscle

Paul and Chris explain in the podcast that slowing down the eccentric phase during regular strength training does not lead to significant muscle growth. Here’s why:

1. Muscle Activation Decreases During the Eccentric Phase  

During the eccentric phase, muscle fibers produce roughly twice as much force with half the activation compared to the concentric phase. The central nervous system (CNS) is more efficient in eccentrics, meaning fewer muscle fibers are required to perform the movement. This means that even though the muscle is under tension, it's not being fully activated, particularly in the fast-twitch muscle fibers responsible for most muscle growth. 

2. Eccentric Phases Target Slow-Twitch Fibers

Slower eccentrics primarily activate slow-twitch fibers, which are less responsive to hypertrophy (muscle growth). Most muscle growth comes from activating fast-twitch fibers, which are more heavily engaged during the concentric (lifting) phase. Slowing down the eccentric portion doesn’t provide the same stimulus for fast-twitch fibers, limiting its muscle-building potential.

3. Old Studies Created Confusion

The belief in the power of slow eccentrics can be traced back to older studies on eccentric overload training, which showed greater hypertrophy compared to concentric-only training. However, these studies involved eccentric overload, where more weight is applied during the lowering phase than the lifting phase, which is very different from simply slowing down a regular eccentric movement. In most strength training programs, no additional resistance is applied in the eccentric phase, so the benefits seen in these old studies don’t apply.

So, Should You Skip Eccentric Training Altogether?

Not at all. As Paul and Chris point out, slow eccentric training does have its benefits, especially when it comes to control and injury prevention. A controlled eccentric phase can help you maintain better form and ensure you're moving through a full range of motion. It may also help in injury prevention by reducing jerky or uncontrolled movements. However, it’s important to understand that it won’t lead to extraordinary muscle growth.

If your goal is maximizing muscle hypertrophy, your focus should remain on:

- Concentric Movements: These are where most of your muscle growth happens, particularly in fast-twitch fibers.

- Progressive Overload: Gradually increasing the weight or resistance you're lifting to continually challenge your muscles.

- Volume and Recovery: Ensuring you're doing enough work and giving your body the time it needs to recover.

Conclusion: Why Slow Eccentrics Aren’t the Key to Muscle Growth

Slowing down the eccentric portion of your lifts won’t unlock a magic door to bigger muscles. As Paul and Chris make clear in their podcast, slow eccentrics primarily engage slow-twitch fibers and won’t stimulate fast-twitch fibers to the degree needed for maximum muscle growth. While there are benefits to including controlled eccentrics in your training for better form and injury prevention, they won’t provide the muscle-building results that some believe.

To listen to the full breakdown on this topic, check out the Chris and Paul Show podcast episode titled "Why Eccentrics Will NOT Build a Lot of Muscle." Delve into the depths of muscle physiology, biomechanics, and anatomy as Paul Carter and Chris Beardsley dismantle this myth and provide evidence-based insights into how to truly maximize your muscle growth.

Ready to optimize your training? Skip the slow eccentrics and focus on the real muscle-building strategies that work with the MAXPRO, the ONLY concentric training device you need.

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