By Team PowerMax / 23 Oct 2024
When it comes to muscle growth, not all hypertrophy is created equal. While most fitness enthusiasts know that lifting weights leads to bigger muscles, fewer understand that there are two distinct types of hypertrophy: sarcoplasmic and myofibrillar. Understanding these types is crucial if you want to tailor your training to meet specific goals, whether it’s maximizing muscle size or focusing on strength. In this blog, we will focus on sarcoplasmic hypertrophy, a form of muscle growth that contributes significantly to muscle size and the aesthetic "pumped" look often seen in bodybuilders.
Let’s dive deep into what sarcoplasmic hypertrophy is, how it differs from other forms of muscle growth, the science behind it, and how you can optimize your training to achieve sarcoplasmic gains.
Sarcoplasmic hypertrophy refers to the increase in volume of the sarcoplasm, the fluid-filled space around muscle fibers that stores glycogen, water, and other essential nutrients. Unlike myofibrillar hypertrophy, which increases the number and size of the muscle fibers responsible for contraction, sarcoplasmic hypertrophy expands the energy reserves within your muscles.
The sarcoplasm is rich in glycogen, ATP (adenosine triphosphate), and other molecules necessary for energy production. When the sarcoplasm swells, it results in increased muscle size, giving muscles a fuller, rounder appearance. However, this type of hypertrophy does not lead to a significant increase in muscle strength, which is why athletes who focus on size (like bodybuilders) often have different training methods than athletes who prioritize strength (like powerlifters).
To understand sarcoplasmic hypertrophy at a deeper level, let’s break down how muscles grow in response to resistance training.
When you perform resistance exercises, you create tiny tears in your muscle fibers. The body responds to this by repairing the damaged fibers and making them stronger and, depending on the type of training, either larger in terms of fiber size (myofibrillar hypertrophy) or by expanding the fluid-filled sarcoplasm (sarcoplasmic hypertrophy).
Sarcoplasmic hypertrophy is largely driven by glycogen storage. Glycogen, stored in the sarcoplasm, is a primary fuel source for muscle contractions during exercise, especially during high-repetition, lower-weight workouts. As your muscles store more glycogen, they also hold more water, leading to an increase in muscle volume. This is the primary mechanism by which sarcoplasmic hypertrophy enlarges muscle size without necessarily increasing strength.
To fully understand sarcoplasmic hypertrophy, it’s important to contrast it with myofibrillar hypertrophy. Here’s a breakdown of the key differences between the two:
The key takeaway here is that sarcoplasmic hypertrophy results in a noticeable increase in muscle size due to increased energy storage and fluid in the muscle, whereas myofibrillar hypertrophy is all about strength and contractile function.
One of the main appeals of sarcoplasmic hypertrophy is its direct impact on muscle volume. The more sarcoplasmic hypertrophy you experience, the larger your muscles will appear, even if the actual strength gains are not as significant.
This is why bodybuilders and athletes who focus on muscle aesthetics often prioritize training that targets sarcoplasmic hypertrophy. By maximizing glycogen stores and increasing water retention within the muscles, they achieve the "pumped" look that is characteristic of bodybuilding physiques. This type of hypertrophy also gives the appearance of rounded, full muscles, which can enhance your overall look.
To maximize sarcoplasmic hypertrophy, your training should emphasize volume and higher repetitions. Here are the key training strategies to help you achieve this form of hypertrophy:
Training with moderate weights for higher repetitions (typically in the 8–15+ range) is the cornerstone of sarcoplasmic hypertrophy training. This style of lifting forces your muscles to work for longer durations, depleting glycogen stores and encouraging the body to store more glycogen over time. As glycogen stores increase, so does the size of the sarcoplasm, resulting in fuller, larger muscles.
To keep the muscles under tension and maximize the metabolic stress that leads to sarcoplasmic hypertrophy, short rest periods between sets (around 30 to 90 seconds) are ideal. This ensures that the muscles remain fatigued, stimulating further glycogen depletion and encouraging the muscle to adapt by increasing glycogen storage.
Focusing on the amount of time your muscles are under tension during each set is another key to achieving sarcoplasmic hypertrophy. The longer the muscles are under tension, the more energy (glycogen) they will require, thus driving the body to increase its sarcoplasmic stores.
One way to increase TUT is to slow down the tempo of each lift, particularly during the eccentric (lowering) phase of the movement. For example, taking 3–4 seconds to lower the weight and then explosively lifting it can increase the stress on the muscles and boost sarcoplasmic hypertrophy.
High training volume is essential for sarcoplasmic hypertrophy. Volume is the total amount of work you do in a workout, and it’s calculated by multiplying the number of sets by the number of reps by the weight lifted. To achieve sarcoplasmic hypertrophy, aim for multiple sets (3–5) of each exercise, with a focus on high repetitions.
Incorporating advanced techniques like supersets (performing two exercises back-to-back with no rest) and drop sets (performing a set to failure, then immediately reducing the weight and continuing) can amplify the metabolic stress and fatigue necessary for sarcoplasmic hypertrophy. These techniques help to maximize glycogen depletion and force your muscles to adapt by increasing their energy reserves.
The most obvious benefit of sarcoplasmic hypertrophy is an increase in muscle size. This type of hypertrophy is particularly appealing to bodybuilders, athletes, and anyone looking to improve their physique. By expanding the sarcoplasm, muscles appear fuller, rounder, and more defined.
While sarcoplasmic hypertrophy doesn’t necessarily lead to increased strength, it does improve muscle endurance. The larger glycogen stores allow muscles to sustain longer periods of activity before fatigue sets in. This can be beneficial for athletes who need to maintain performance over longer durations, such as in sports like cycling or long-distance running.
For many individuals, the aesthetic appeal of sarcoplasmic hypertrophy is the primary motivation for focusing on this type of training. The increased muscle size and fullness create a more muscular and defined appearance, which is especially desired in bodybuilding and fitness competitions.
The muscle "pump" that you feel during a workout is largely due to sarcoplasmic hypertrophy. As more glycogen and water are stored in the muscles, they swell, creating the tight, pumped sensation that many bodybuilders seek during their workouts. This pump can also serve as an indicator that your muscles are being adequately stimulated for growth.
While sarcoplasmic hypertrophy offers many benefits, it’s important to be aware of its limitations, particularly if your goals extend beyond muscle size.
One of the main drawbacks of sarcoplasmic hypertrophy is that it doesn’t contribute significantly to strength gains. If your primary goal is to lift heavier weights or improve your performance in strength-based sports like powerlifting or Olympic lifting, you’ll need to focus more on myofibrillar hypertrophy, which directly targets the muscle fibers responsible for contraction.
Because much of the muscle size gained through sarcoplasmic hypertrophy is due to increased glycogen and water retention, the effects can be somewhat transient. If glycogen stores are depleted (for example, during periods of reduced carbohydrate intake or overtraining), muscles may temporarily shrink. This is why some athletes experience a decrease in muscle size during cutting phases when their carbohydrate intake is lower.
As with any training method, the body adapts over time. If you consistently focus on high-rep, high-volume training without incorporating variation, your progress may plateau. To prevent this, it’s essential to cycle your training, incorporating phases of myofibrillar hypertrophy and strength work to continue making progress.
Sarcoplasmic hypertrophy is a powerful tool for anyone looking to increase muscle size and achieve a fuller, more aesthetic physique. By focusing on high-repetition, high-volume training with short rest periods, you can maximize glycogen storage and increase the size of the sarcoplasm, resulting in visibly larger muscles. However, it’s essential to remember that this type of hypertrophy doesn’t necessarily translate to strength gains, so it’s important to tailor your training to your specific goals.
For those looking to strike a balance between size and strength, incorporating both sarcoplasmic and myofibrillar hypertrophy into your training program can yield the best results. Understanding how these different types of hypertrophy work can help you fine-tune your workouts and unlock the full potential of your muscles.
