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Muscle mass and strength slowly decline with age, a process doctors call sarcopenia. Strength training and a diet with enough protein can markedly slow the loss, and even people in their nineties can still grow stronger.

Geriatric medicine

HealthScience

The story behind the card

The word comes from the Greek sarx, flesh, and penia, poverty or loss. The nutrition researcher Irwin Rosenberg proposed it in 1989, arguing that no change of ageing was more dramatic or mattered more for independence than the loss of lean body mass. One review puts the loss of muscle mass at roughly 3 to 8% per decade after the age of 30, faster after 60, though rates vary widely by person and by how muscle is measured. The loss is not fixed: in a 1990 study at a Boston nursing home, nine frail residents aged about 90 increased their leg strength by an average of 174% after eight weeks of weight training, and walked faster too.

Türkçe oku
Kas kütlesi ve kas gücü yaş ilerledikçe yavaş yavaş azalır; hekimler buna sarkopeni der. Kuvvet antrenmanı ve yeterli protein içeren beslenme bu kaybı belirgin biçimde yavaşlatabilir; doksanlı yaşlardaki insanlar bile güçlenebilir.

Sözcük Yunanca sarx (et) ve penia (yoksunluk, kayıp) sözcüklerinden gelir. Beslenme araştırmacısı Irwin Rosenberg 1989'da bu adı önerdi; ona göre yaşlanmayla gelen hiçbir değişiklik, yağsız vücut kütlesindeki kayıp kadar çarpıcı değildi ve insanın kendi başına yaşayabilmesini bu kadar etkilemiyordu. Bir derlemeye göre kas kütlesi 30 yaşından sonra her on yılda yaklaşık %3 ile %8 arasında azalıyor, 60'tan sonra bu hız artıyor; ama oran kişiden kişiye ve ölçüm yöntemine göre çok değişiyor. Bu kayıp kader değil: 1990'da Boston'daki bir huzurevinde yapılan bir çalışmada, 90 yaş civarında ve bakıma muhtaç dokuz kişi, sekiz haftalık ağırlık çalışmasının ardından bacak güçlerini ortalama %174 artırdı ve daha hızlı yürümeye başladı.

Sources and further reading

Background reading: Sarcopenia
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