Peptidele hormonale: alternativa sigura la steroizi?

Peptidele hormonale utilizate in culturism sunt un fel de substante despre care se spune ca sunt varianta mai sigura si legala a steroizilor anabolizanti si androgeni.

In ultimii ani vanzarile de astfel de peptide au explodat, uneori si datorita unor producatori de suplimente care le-au folosit si au pretins ca pot creste masa musculara, pot imbunatati arderile grasimilor si pot face toate astea in mod natural si sigur. Este adevarat? Sunt peptidele hormonale la fel ca steroizii? Mai toate plusurile dar fara efectele secundare negative? In continuare gasesti raspunsurile. 

Ce sunt peptidele hormonale?

Termenul de "peptida" se refera la orice molecula alcatuita din 2 - 50 aminoacizi uniti intre ei prin legaturi peptidice. Peptidele exista in mod natural in corpul uman si al animalelor dar si in plante cu continut de proteine. Pot fi si sintetizate artificial in laborator. 

Cand vorbim de peptidele hormonale din culturism ne referim la cele sub forma de pudra sau injectabile care stimuleaza secretia de hormon de crestere (HGH), numite si peptide secretagog al hormonului de crestere. Acestea stimuleaza hipotalamusul sa secrete mai mult hormon de crestere.

Care sunt beneficiile peptidelor hormonale din culturism?

Sporirea nivelurilor de hormon de crestere este ceva foarte dorit de culturisti pentru ca mobilizeaza grasimea corporala, ceea ce inseamna ca ajuta la eliberarea acizilor grasi stocati in celulele grase, facand mai usoara arderea grasimilor si conservarea masei musculare. Hormonul de crestere mareste si secretia de IGF-1, care mareste masa musculara si sporeste si mai mult arderile grasimilor. 

Asadar, logica este ca daca folosesti peptide hormonale de tipul secretagog vei slabi si vei acumula grasime in acelasi timp. Si cum este legal sa cumperi astfel de peptide (datorita unei chichite care tine de etichetare, o sa vorbim si despre asta) si sunt considerate relativ sigure, sunt vazute ca o alternativa mai sanatoasa la steroizii anabolizanti. 

Asta presupunand ca functioneaza, ceea ce este discutabil. 

Exista dovezi solide ca mecanismul prin care imbunatatesc compozitia corpului exista si functioneaza, dar nu exista multe dovezi ca functioneaza asa cum spera multi culturisti.
De exemplu, cercetari facute la Universitatea din Chile, la Centrul Medical pentru Copii Schneider din Israel si la Universitatea din Washington, arata ca peptidele hormonale sunt eficiente in cresterea nivelurilor de HGH si IGF-1 la copii mici prepubertate. Asta arata ca peptidele hormonale sunt de un mare ajutor pentru ca toti copiii mici sa cresca la fel de inalti ca ceilalti copii, nu sunt dovezi concrete ca pot ajuta un adult de 35 de ani sa slabeasca si sa construiasca masa musculara. 

Alte studii arata ca peptidele hormonale au efecte pozitive in randul varstnicilor si celor infirmi. Au fost studii in care pacientii care sufereau de cancer pulmonar si luau peptide hormonale secretagoge cresteau mai bine in greutate decat cei care nu luau. La fel, masa musculara crestea mai mult la batranii care se recupereau dupa fracturi. Din nou, este dificil sa vezi daca aceste studii se aplica si tinerilor sanatosi. 

Sunt si studii care arata ca aceste peptide pot ajuta obezii sa slabeasca, dar rezultatele nu se aplica neaparat si celor cu greutati mai mici, pentru ca perosanele obeze tind sa aibe o secretie deficitara a hormonului de crestere, asa ca raspunsul la tratament nu este mereu la fel si la persoanele cu greutati sanatoase. 

Au existat si cateva studii care au analizat efectele asupra unor persoane sanatoase si cu niveluri normale de grasime, si au aratat efecte pozitive in general, dar si aceste studii au fost facute pe esantioane mici (numar mic de participanti) si unele au avut anumite erori de organizare care fac dificila extrapolarea lor la omul de rand care merge la sala. 

Ar trebui sa folosesti peptide hormonale?

Asta depinde de tine. Dar retine ca nu exista dovezi concrete ca te pot ajuta, daca esti un impatimit de fitness care merge la sala regulat, are grija ce mananca si are in general un stil de viata sanatos. Dupa cum am spus, studiile sunt promitatoare, dar nu exista dovezi definitive ca te pot ajuta. 

Argumentele teoretice par solide, si exista multe povesti de succes ale celor care au folosit peptidele hormonale, dar toate acestea nu sunt dovezi concrete ca functioneaza. 

Si cel mai important, inca nu exista date pe termen lung privind eficienta si efectele secundare. Studiile arata ca nu exista efecte adverse daca iei peptide hormonale cateva saptamani sau luni, dar nu se stie ce se intampla cand le iei mai multi ani, chiar daca in cure separate, si nici daca exista efecte secundare care apar mai tarziu (precum cancer, boli de inima, etc.).

Exista si efecte nedorite de la peptide, doar ca nu grave. Multe studii au raportat efecte secundare precum transpiratii mai abundente, bufeuri de caldura si inrosirea pielii, dureri musculare medii, retentia de fluide, somn perturbat si cresteri ale nivelurilor de cortizol si prolactine. 

Unele astfel de peptide au ca efecte secundare cresterea apetitului si scaderea sensibilitatii la insulina, ambele putand opri efortul de a slabi.

Si legalitatea peptidelor hormonale este dubioasa. Este interzisa vanzarea de peptide hormonale ca si suplimente dar permisa vanzarea lor ca "substante de cercetare" sau "nu pentru consumul uman".

Teoretic, singurii care ar avea voie sa cumpere peptide ar fi cercetatorii care fac experimente cu ele. Desigur, majoritatea peptidelor hormonale vandute online nu ajung in laboratoare, ci la culturisti, sportivi si pasionati de fitness care incearca sa devina mai definiti si masivi. 

Asadar piata peptidelor hormonale este dubioasa in ansamblul ei si nu stii sigur ce cumperi si nici macar ce efecte va avea. 

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