Published online by Cambridge University Press: 01 February 2007
Average world life expectancy has seen a dramatic rise over the last two centuries although active life expectancy remains relatively unchanged. One reason for this is that aging results in skeletal muscle becoming smaller, weaker and more susceptible to contraction-induced injury. By the age of 70, muscle strength is reduced by around 30–40% and this can have catastrophic effects on quality of life. Despite a vast amount of research into age-related changes in skeletal muscle, the exact mechanisms responsible for this is still unclear and thus treatments to preserve muscle function with aging remain elusive.