The Science Behind Building Muscle: What You Need to Know
Introduction
There are those whose gym gains are downright enviable. Their muscles tell stories of discipline and dedication. And then there are others who keep sweating it out on the floor but, frustratingly, do not have much to show for it.
It often boils down to understanding the science behind building muscle and nailing the methods that truly count.
Ask any fitness enthusiast, and they will tell you how getting that perfect physique is what they dream of. Turns out they are not alone. According to a recent survey conducted in 2024, building muscles was the top fitness goal for almost a third of the people asked.
But clearly, there is more to building muscle mass than just grinding it out in the gym.
Read on to find out all you need to know about building muscle with a bit of science on your side!
The Magic Behind Muscle Growth
When you flex your bicep, you are triggering thousands of tiny muscle fibres, each one being a muscle cell composed of even smaller structures called sarcomeres.
Sarcomeres contain contractile proteins, actin and myosin, that are responsible for muscle contraction. When your brain signals your muscle to move, the contraction starts at this microscopic level.
Muscle growth, scientifically referred to as skeletal muscle hypertrophy, occurs when additional myosin filaments are added to these muscle fibres.
Over time, this process strengthens and enlarges the muscle, making the fibres, and ultimately the muscle, larger and more powerful. It is this chain of events that forms the basis of building muscle mass.
Building Muscle Mass or Hypertrophy
Hypertrophy is the growth or increase in the size of the skeletal muscle fibres. This happens as a result of many processes, both mechanical and chemical.
Once we have an understanding of these mechanisms, we can greatly improve the effectiveness of a workout regimen.
Mechanical Tension:
This is sometimes considered the most important part of muscle building.
When we lift a load, we place stress on the muscle fibres creating tension. As a result, the body starts a series of processes that help in muscle growth.
Studies show that a high form of mechanical tension such as the kind generated during intense resistance training is directly linked to muscle hypertrophy, or the enlargement of muscles.
Whether we perform heavy lifts or focus on higher repetitions, each workout adds to the mechanical stress on our muscles. The result is growth and advancements in the fitness journey.
Metabolic Stress:
Metabolic stress is the second factor important for building muscles, which increases muscle cell size. According to a study, there needs to be metabolic stress alongside mechanical damage to help in building muscle.
When we engage in an exercise repeatedly, we are putting in a sustained effort which results in an accumulation of lactate and hydrogen ions. This disturbs the chemical balance of the muscles causing the body to react.
The body responds by sending anabolic signalling pathways which trigger muscle growth genes.
Notably, low-intensity resistance exercises performed under reduced blood flow have been shown to enhance metabolic stress, contributing to muscle size and strength gains.
Therefore, the combination of intensity and the buildup of metabolic by-products helps in muscle growth by forcing the body to adapt to these new conditions.
Muscle Damage:
Muscle damage is the third factor involved in muscle growth. It may sound contradictory at first but the opposite is true.
During intense physical exercise, particularly resistance training, muscle fibres experience microtrauma or tiny tears. This damage is followed by an inflammatory response, which helps set off the muscle repair process.
When the body repairs these damaged fibres, it restores them, strengthening them at the same time. The result is an increased muscle size.
The greater the mechanical load on muscles, the more microtrauma occurs, which in turn enhances the muscle repair and growth process.
However, excessive damage can slow recovery down, so it is absolutely essential to balance training intensity with adequate rest and recovery to optimise hypertrophy.
The Contribution of Other Factors
Hormonal Responses:
Exercise induces the release of anabolic hormones such as testosterone, insulin-like growth factor, and human growth hormone (HGH).
These hormones speed up the repairing and growing of muscle fibres, i.e. protein synthesis. The more of these hormones circulate in the body post-workout, the greater the potential for muscle growth.
Protein Synthesis vs. Breakdown:
Muscle growth occurs when protein synthesis (the building of new muscle fibres) is faster than protein breakdown (the natural wear and tear of muscle fibres).
Resistance training increases protein synthesis, while proper nutrition, particularly protein intake, is the way to ensure that the body has the necessary materials to build and repair muscle.
On the whole, building muscle needs consistent resistance training, creating muscle damage and proper nutrition.
Building Muscle with Nutrition
Macronutrients
Protein:
- Building muscle depends upon protein intake as it is the most crucial macronutrient for the process.
- It plays a major role in repairing muscle fibres, making them stronger and larger in the process. The amino acids found in protein are the building blocks for muscle growth and repair.
- Quality sources include lean meats, fish, eggs, dairy, and plant-based options like beans and legumes.
Carbohydrates:
- Carbs are needed to fuel workouts and aid in the recovery process.
- When we consume carbohydrates, they break down into glucose providing us with immediate energy for exercise.
- Complex carbohydrates, like whole grains, beans, and starchy vegetables, are excellent sources to support both performance and recovery.
Fats:
- Healthy fats are used in hormone production, including the growth hormone, which is needed for muscle growth.
- Fats also help with the absorption of fat-soluble vitamins (A, D, E, and K), which are essential for overall health.
- Consuming essential fatty acids from sources like avocados, nuts, seeds, and oily fish supports hormonal balance and recovery.
Micronutrients:
Micronutrients, including vitamins and minerals, are often overlooked but are needed for muscle function and recovery. For example:
- Vitamin D is required for muscle function and bone health.
- Magnesium helps with muscle relaxation and recovery.
- Zinc supports hormone production and immune function, both of which are important for muscle recovery.
- Calcium allows actin and myosin to interact for muscle contraction.
Final Word
Building muscle requires us to work hard and smart.
Understanding the science behind muscle growth gives us the tools to hit our goals faster, with better results. By nailing our technique, fuelling up with the right nutrition, and allowing time for recovery, we are setting ourselves up for some serious gains.
So next time you are in the gym, remember: it is all about a balanced approach. Go ahead and make those workouts count!
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