Hypertrophy rules

What is muscle hypertrophy?

Hypertrophy is a medical term, meaning an increase in the whole organ or part of it as a result of the growth in volume and / or number of cells( 1).By hypertrophy of muscles is meant an increase in the total muscle mass of the organism due to the growth of individual groups of skeletal muscles.

In fact, hypertrophy is the main goal of training in fitness and bodybuilding, since without physical growth of muscles it is impossible both to increase their strength and increase volume. In simple terms, strength training is an exercise in hypertrophy.

Details on how to eat for muscle growth. Recommendations for calorie, nutrients and additives.

Types of muscle hypertrophy

There are two types of muscle hypertrophy - myofibrillar and sarcoplasmic. The first is achieved by increasing the volume of muscle fiber cells( with the number of cells practically unchanged), the second - by increasing the nutrient fluid surrounding this fiber( 1).

The musculature recruited by the athlete as a result of different types of hypertrophy( and different types of training) is different from each other. Myofibrillar hypertrophy is characterized by "dry" and tightened muscles, whereas sarcoplasmic hypertrophy is more voluminous and "pumped up".

Myofibrillar hypertrophy: muscle strength

Myofibrillar hypertrophy involves the growth of muscle fiber and the increase in muscle strength with a moderate increase in volume. The necessary strategy of training is basic exercises with a serious working weight and a small number of repetitions( 3-6) in each exercise.

The key point of myofibrillar hypertrophy is the use of maximum working weight in exercises( about 80% of the weight of one maximal repetition) and constant progress and increase of this working weight. Otherwise, the muscles will adapt and stop growing( 2).

Sarcoplasmatic hypertrophy: muscle volume

Sarcoplasmic hypertrophy implies an increase in muscle volume due to an increase in the capacity of the energy depots of muscles( sarcoplasmas).The increase in muscle strength is not the main thing. The training strategy is a moderate load, a high number of repetitions( 8-12) and sets.

Examples of sarcoplasmic hypertrophy are endurance training( marathon run, swim) and pumping( performing weight exercises with medium weight and high repetitions).Most often it is pumping used to increase muscle volume without increasing strength.

Types of hypertrophy and types of muscle fibers

Fast( white) muscle fibers respond better to myofibrillar hypertrophy, and slow( red) - to sarcoplasmic. The difference between types of fibers is obvious on the example of a hen - white meat on the wings( for sharp and intense strokes) and red on the legs( static loads).

Actually weight training with extra weight develops white( fast) muscle fibers, whereas for the development of red( slow) exercises, static exercises, stretching and yoga will be required. In addition, slow muscle fibers develop in runners for long distances.

What is the difference between sports metabolism? Signs of a genetic predisposition to bodybuilding.

Rules of training for hypertrophy of muscles

  1. Use a significant working weight in the exercises. Stress is the key to triggering hypertrophy and muscle growth processes - which is why it is important to use heavy working weights in the exercise and constant progression. Otherwise, the muscles will adjust and stop being stressed.
  2. Do not exceed the recommended number of sets. The total number of sets( approaches) per muscle group should be in the range from 10 to 15( 3-4 exercises for 3-4 approaches).With a sufficient load on the muscles in these sets, an increase in the number of sets will not give an additional increase in the effectiveness of the training.
  3. Let the muscles have time to repair .In strength training, energy reserves in the working muscle are expended in 10-12 seconds( which is why a low number of repetitions is recommended).To restore it is necessary from 45 to 90 seconds - hence the recommendation is made for a fairly long rest between the sets.
  4. Take supplements for muscle growth .Muscle fiber fuel is a fast source of energy - creatine-phosphate, BCAA and glycogen( 3).The intake of creatine, whey protein and carbohydrates with a high glycemic index before training, as well as BCAA amino acids at the time, helps muscles grow faster.


Muscle hypertrophy refers to the growth processes of muscle fiber and its surrounding nutrient fluid. There are two types of hypertrophy. In force training, they act synergistically, but with a greater emphasis on myofibrillar hypertrophy of fast muscle fibers.

Scientific sources:

  1. Muscle hypertrophy, source
  2. Hypertrophy and Muscle Growth, source
  3. Muscle Growth: Why, And How, Does A Muscle Grow And Get Stronger, Casey Butt, Ph. D., source