Edited by Antonio Martorella
Muscle hypertrophy is an adaptation that our body implements in response to a stimulus given by an overload. However, the increase in volume is not determined only by an increase in the number (hyperplasia) and thickness of the myofibrils. There are other components within the muscle that contribute to increasing the volume: ATP, glycogen, phosphocreatine, connective tissue, capillary vessels and mitochondria. We should also take into account the fact that, in each muscle, both fast (FT) and slow (ST) fibers coexist and that the two types of fibers should be trained differently. This brief introduction should make us understand that there is no effective method for hypertrophy, but there are different methods of muscle stimulation, each of which will produce changes that will globally lead to hypertrophy.
Let's analyze what are the methods to train the muscle in its entirety. The following table shows how the various cellular components contribute to the total volume and the specific training mode:
| CELL COMPONENTS | Contribution in% to cell volume | Training method |
myofibrils | 20-30 | Strength work - 6-12 repetitions. Rest |
Mitochondria | 15-25 | Resistance work - 15-25 repetitions. Rest |
sarcoplasma | 20-30 | Work of strength and endurance |
capillary | 3-5 | Resistance plus extended tension |
Fat deposits | 10-15 | Rest and diet |
Glycogen | 2-5 | Diet |
Connective tissue | 2-3 | Power |
Other substances | 4-7 | Strength, endurance, rest and diet |
As can be clearly seen, almost 90% of muscle volume is given by: myofibrils, mitochondria, sarcoplasm and capillaries. To stimulate the increase both in number and size of the myofibrils, it will be necessary to work with loads ranging from 75% to 85% of the ceiling on a repetition. The white fibers (FT) will respond better to loads of 80-85% of the ceiling with fast, explosive movements and a low number of repetitions. The red fibers (ST) will instead be maximally stimulated by loads between 70 and 80% of the ceiling with slower movements and a greater number of repetitions. Training with loads on the order of 60% of the ceiling, slow movements and a high number of repetitions will increase both the number of mitochondria and the capillaries that surround the muscle cell. From all this it is therefore evident that training with overloads MUST necessarily include long series (15-30 repetitions), especially for large muscle groups.
Obviously, for a workout to be effective, we need to take into account numerous other variables that would need each of a separate discussion. For the moment I limit myself only to focus on the INTENSITY of training and the EXECUTIVE TECHNIQUE of the exercises. Following intense training, an increase in blood lactic acid occurs. The consequent lowering of blood pH leads to a considerable increase in GH (growth hormone). Furthermore, lactic acid causes micro-lesions at the muscular level which in the recovery and supercompensation phase lead to increased protein synthesis. Considering that the energy substrate of the lactate system is glycogen we will see a supercompensation at its retention level. The movement performed slowly, especially in the eccentric phase, produces a mechanical deformation at the level of the nucleus of the muscle cell. This has a very positive effect on increasing protein synthesis. Furthermore, eccentric movement and isometric contraction cause considerable damage to the muscle cell which leads to the release of muscle-specific growth factors such as IGF-1.
So when you are training seriously, we try to understand what we are doing and above all why we are doing it in a certain way. There are no "magic" cards or miraculous exercises. Always rely on competent people who will teach you "how to train" and will advise you on the most suitable exercises, since the training card is ABSOLUTELY personal and is built exclusively on you.
