Creatina este cunoscuta pentru imbunatatirea performantelor fizice. Dar uneori a fost promovata si ca booster de testosteron. Un supliment care ar creste atat performantele cat si testosteronul ar fi regele suplimentelor legale, dar este adevarat ca poate creatina creste nivelurile de testosteron?
De unde vine ideea
Suplimentele sunt de regula testate privind efectul asupra hormonilor, mai ales daca au proprietati anabolice, precum creatina: prin regenerarea adenozin trifosfatului (ATP), principala forma de energie a celulelor, creatina te ajuta sa ridici mai greu si mai intens, iar munca in plus duce la cresteri musculare mai mari.
Acest efect anabolic, fiind mediat de o crestere a intensitatii antrenamentelor, este indirect. Dar ar putea avea creatina si un efect anabolic direct? Ar putea ea creste testosteronul? Astfel de intrebari ii imping pe cercetatori sa caute raspunsuri prin studii.
In cazul creatinei, exista posibilitatea unui efect indirect asupra testosteronului. Stim ca ridicarea de greutati duce la o crestere de scurta durata a nivelurilor de testosteron, si stim ca poti ridica greutati mai mari cand iei creatina, asa ca teoretic sa iti alimentezi antrenamentele cu creatina ar duce la o crestere mai mare a testosteronului!
In general, trei studii controlate si randomizate sunt citate pentru a sustine ideea ca a lua creatina duce la cresterea nivelurilor de testosteron.
Primul nu a aratat cresteri ale testosteronului, ci cresteri de 12 ng/dl ale dihidrotestosteronului (DHT) un hormon andorgen foarte activ, derivat din testosteron.
Studiile doi si trei, subiectii care au luat creatina au trecut prin cresteri ale testosteronului, comparativ cu grupurile de control.
Ce spun alte studii?
Alte zece astfel de studii cu un total de 218 participanti au studiat efectele creatinei asupra testosteronului. Au avut doze care au variat de la 3 la 25 de grame pe zi. Toate au raportat ca nu exista efecte asupra testosteronului. 9 din cele zece studii au folosit creatina monohidrat, iar unul pe cea malat. Subiectii din toate studiile au fost tineri sanatosi, nu s-au facut cercetari pe subiecti care aveau niveluri prea mici de testosteron.
Trebuie sa tinem cont si de durata studiilor. Cele care au ararat efecte asupra DHT au fost facute pe 1-3 saptamani, pe cand cele mai lungi, pana la 12 saptamani, nu au ararat niciun efect. Studiile mai lungi nu sunt neaparat mai bune decat cele scuirte, dar tind sa aibe o semnificatie pragmatica mai mare.
Concluzii
Suplimentarea cu creatina creste performantele fizice, dar nu exista dovezi ca ar creste direct nivelurile de testosteron. Daca vrei sa iti optimziezi nivelurile de testosteron, dormi suficient, antreneaza-te cu greutati, mananca suficiente grasimi, ia vitamina D, magneziu si zinc.
Referinte
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