Cross training and cross fitness. Introduction to the method

Edited by Dr. Davide Traverso

Meso-ectomorph
In this group we find people with both meso and ectomorph characteristics. The tendency is towards the long-limbed ectomorph, with a stronger and stronger upper body and slender lower limbs. With these clients the hardest part of the job will be in the "obtain a harmonious development of the lower limbs with respect to the trunk.

Meso-endomorph
Physical structure intermediate between meso and endomorph, they have a good balanced and muscular structure, powerful legs and rounded hips. The main problem of these subjects is the tendency to accumulate fat, especially in the abdomen region.

Anticipating what will be treated in the chapter dedicated to training, the mesomorphic subject will tend to have no problems in carrying out any type of program, both based on volume and intensity. The ectomorphic biotype, as regards the development of muscle mass, will generally obtain good results from "intensity" training, less from volume training. His greatest enemy is cortisol, which does not allow him to build muscle mass. Strength training must be short and intense. Body building authors define these “hard gainer” subjects, that is hard to grow, due to their difficulty in increasing muscle mass. The endomorphic biotype, as far as strength training is concerned, will more easily obtain results from volume training, less from intensity training. Of course these considerations, the result of the experience of various authors, are not strict rules, but must be adapted to several cases, after a "careful observation and evaluation of the results by the" expert instructor.

The energetic substrates

To understand a training program, even more in a cross fitness key, we need to know the mechanisms of muscle work, and what are the energy sources that the muscle draws on in order to contract and consequently generate strength and displacement. These mechanisms are very complex and their in-depth discussion is not necessary in this context: let's analyze them in the simplest possible way.

Muscle contraction requires energy provided by food. This chemical process requires an intermediary, "ATP. The" ATP (adenosine triphosphate) is used for muscle contraction and resynthesized through various mechanisms.

The aerobic mechanism
is the mechanism by which the muscle cell degrades substrates, carbohydrates and lipids, in the presence of oxygen. ATP is produced inside the mitochondria, cellular organs that we can consider the lungs of the cell. This mechanism has an enormous yield and a theoretically infinite capacity to extend the work over time. The "intensity of work" must be relatively low, otherwise the anaerobic lactacid metabolism will be involved. This mode of energy production, in the field of motor activity, is used in the work for the development of endurance. It is the type of metabolism we use every day to carry out our daily life, go to work, shop, carry out housework etc.

The anaerobic lactacid mechanism
It allows to re-synthesize ATP starting from the degradation of glucose (glycolysis). Glucose represents 99% of the sugar present in the body; it is stored in the form of glycogen in the liver and skeletal muscles. This energy process produces lactic acid.
The mechanism has two constraints: the first is the glycogen storage limit in the human body; the second is the need to dispose of lactic acid. For this reason the anaerobic lactic acid metabolism can support intense effort for a limited time. The accumulation of lactic acid, after a certain time, blocks muscle contraction; with training it is possible to improve tolerance to lactic acid, but be careful! The production of lactic acid is a defense mechanism, which stops the contraction before the muscle can be damaged. For this reason we hardly find muscle tears in people with a medium-low athletic ability: their low tolerance to lactic acid interrupts their ability to work before there can be possible injuries. The series is mainly composed of high-level athletes: their tolerance to lactic acid has risen thanks to the important training load, there is no alarm signal that heralds a possible injury. It is a mistake to justify post-workout muscle pain with lactic acid buildup; a marathon runner disposes of the lactic acid he produced during a race in three hours. The lactic acid anaerobic mechanism is involved in weight training and in the execution of stretches.

The alactacid anaerobic mechanism
It lasts from three to fifteen seconds and allows for maximum strength performance. It uses as an energetic substrate the ATP present in the muscle, and its limited ability to resynthesize itself using the phosphate present in the muscle cell. We use this energetic mechanism in lifting very high weights for a limited number of repetitions, and in performing sprints.