Growth hormone and its effects

Growth hormone, an anabolic hormone

Unlike other hormones, growth hormone is perfectly suited to its name, since it is directly linked to the growth of the body's cells. As we shall see, growth hormone is anabolic for all our body's metabolisms, and thus has multiple beneficial effects.

Growth hormone is anabolic for carbohydrate metabolism, but also for lipid metabolism. In fact, it is this same growth hormone that promotes the mobilization of lipid reserves.

However, growth hormone remains one of the most studied hormones for its anabolic virtues on protein metabolism.

Growth hormone and IGFs

Like all anabolic hormones, growth hormone is often presented as acting directly on protein synthesis. However, the process is somewhat more complex. Growth hormone secretion will diffuse into our bloodstream, and this increase in growth hormone levels will in turn promote the secretion of insulin-like growth factors, hereafter abbreviated to IGFs.

Produced by the liver or derived from fats and muscle cells, these IGFs bind to muscle cell receptors? This is how the anabolic effects of this growth hormone come into play.

The hormone's anabolic effect

Bearing in mind this particular function (growth hormone promotes the appearance of IGFs, enabling the hormone's beneficial effects to be fully felt), it's essential to return to the benefits of protein synthesis.

It is thanks to this protein synthesis that muscle cells are able to build and develop, leading to growth in muscle mass. It's also worth taking a closer look at this growth in muscle mass.

Muscle mass growth

Muscle growth results from the repair of our muscle fibres. The latter, subjected to training, are therefore damaged by the repetition and intensity of effort. Our organism then reconstitutes these muscle fibres, ensuring that they can withstand such efforts. In this way, the muscle is reconstituted to a greater extent, creating the famous muscle mass gain.

As we know, the latter is the result of protein synthesis, and it follows from the above that this growth in muscle mass requires our body to have the time it needs to "repair" itself, as well as all the nutrients it needs to carry out this process.

So, while growth hormone promotes muscle growth (via protein synthesis), we also need to take into account our diet in general, as well as rest and recovery time.

Tailor-made training to take advantage of these benefits

Since we know more or less precisely the beneficial effects of growth hormone secretion on the body, we might be forgiven for thinking that all we have to do is follow a variety of training programs to see this secretion increase in the same proportions. However, numerous studies have been carried out, and it can be argued that the secretion of growth hormone depends on the nature of the training. To be clearer and more practical, blood levels of growth hormone and IGFs are not the only elements to be taken into account, as the nature of training will also be one of the factors influencing the benefits of this hormone. It's natural to distinguish between two types of training: aerobic training and strength training. These have different effects.

Growth hormone and aerobic exercise

For aerobic exercise, it's intensity that seems to determine growth hormone secretion. High-intensity exercise is therefore more beneficial in terms of growth hormone secretion. The growth hormone released in this way in our bodies will then promote fat metabolism, accelerating and facilitating the utilization of lipids stored in the body. Studies demonstrate the importance of this intensity, noting that the effect is most marked after 10 minutes of intensive exercise, performed at around 70% of VO2 MAX.

Growth hormone and bodybuilding training

When it comes to bodybuilding training, the key question is whether to focus on intensity or volume. Is the multiplication of light sets more or less beneficial than more limited sets with heavier loads? It's on this debate between intensity and volume that scientific studies have provided an answer, enabling us to adapt the various training sessions.

A higher secretion of growth hormone is observed when more sets are performed at reduced intensity. The difference in growth hormone levels can then be significant, and studies show that the gain is much greater with higher volume and low or moderate intensity than with low repetition but high intensity training. The proliferation of studies also means that the optimum technique for seeing growth hormone increase in the body would be to mix the two types of training.

Hormone after training

If growth hormone is also to be studied in relation to the exercises that triggered its secretion, it's also important to emphasize that in the case of low-intensity (or moderate-intensity) but high-volume workouts, the level of this hormone remains high even 90 minutes after the end of the workout. However, as mentioned above, it's in the two hours after training that growth hormone is most beneficial in terms of anabolism.

Growth hormone and diet

We've found that, while growth hormone is beneficial in all training programs, whether bodybuilding or other activities, it is also secreted in greater quantities when we undergo these same training sessions. A virtuous circle therefore seems to be taking shape. It's also important to look at the various methods of stimulating greater secretion of growth hormone.

Diet is one of them. It has been observed that growth hormone production is inversely linked to blood sugar levels. So, the higher the sugar level, the lower the level of this hormone, and vice versa. Growth hormone is thus linked to insulin, another anabolic hormone. To promote the secretion of this growth hormone, we need to control blood sugar levels, notably by banning all fast sugars. These fast sugars should be avoided, especially before training sessions.

Sources: - Effects of growth hormone on skeletal muscle

Author Alexandre CARPENTIER

Bodybuilding Champion N.A.C 2012

Alexandre shares his bodybuilding experience with MegaGear blog readers