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Working muscles do more than move you: when they contract, they release chemical messengers called myokines that travel in the blood and act on other organs. In that sense, muscle is also a hormone-producing organ.

Exercise physiology

HealthScience

The story behind the card

The Danish physiologist Bente Klarlund Pedersen and colleagues proposed the name 'myokines' in 2003 for signalling molecules released by muscle. One of the first identified was interleukin-6, which can rise up to a hundredfold in the blood during long exercise. In other settings it is linked with inflammation, but released from working muscle it appears to have mainly anti-inflammatory effects. Myokines are one route by which physical activity affects metabolism, inflammation, fat tissue, bone and the brain, which helps explain some of exercise's wide health benefits. Which molecules are released, and what they do, depends on the kind and intensity of activity, so the idea is broader than a single 'exercise hormone'.

Türkçe oku
Kaslar yalnızca hareket etmemizi sağlamaz: Kasıldıklarında miyokin adı verilen kimyasal haberciler salgılar, bunlar da kanla taşınıp başka organları etkiler. Bu açıdan kas, hormon salgılayan bir organ gibi de çalışır.

Danimarkalı fizyolog Bente Klarlund Pedersen ve ekibi, 2003'te kasın salgıladığı sinyal molekülleri için “miyokin” adını önerdi. İlk tanımlananlardan biri interlökin-6'ydı: Uzun süren egzersiz sırasında kandaki düzeyi yüz katına kadar çıkabilir. Başka durumlarda iltihapla ilişkilendirilen bu molekül, çalışan kastan salgılandığında daha çok iltihabı yatıştırıcı bir etki gösteriyor. Miyokinler, fiziksel etkinliğin metabolizmayı, iltihabı, yağ dokusunu, kemiği ve beyni etkilediği yollardan biridir; egzersizin bu kadar geniş sağlık yararlarının bir kısmını da açıklar. Hangi moleküllerin salgılandığı ve ne işe yaradığı egzersizin türüne ve şiddetine göre değişir; yani konu tek bir “egzersiz hormonu”ndan çok daha geniştir.

Sources and further reading

Background reading: Myokine
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