Introduction
Aging is an inexorable biological process, but its visible consequences — loss of strength, stamina and mobility — need not be accepted as inevitable and untreatable. A new, unusually long-term study from researchers at the Karolinska Institutet adds important detail about exactly when—and how quickly—physical capacity declines in the general population. The key message is both worrying and encouraging: measurable decline begins decades earlier than many assume, yet regular physical activity can substantially blunt that decline, even when begun later in life.


