Compression of morbidity is a hypothesis suggesting that advances in medical science are causing, or will cause, a compression of the terminal period of frailty, illness, and disability at the end of life, squeezing it into an ever-shorter fraction of the overall human life span. In colloquial use compression of morbidity is often spoken of as a practical goal by medical researchers who do not wish to talk openly about extending human life for political or funding reasons.
There is data to support the existence of compression of morbidity with respect to the effects of lifestyle choices on longevity, such as exercise. When it comes to advances in medical science, however, it seems unlikely that gains in life expectancy will forever lag behind gains in health. Consider aging in terms of accumulated damage, for example: if we find ways to repair that damage, then the overall life expectancy will increase, just as it does for any complex machine that is better maintained.
In any case, here is an example of present data supporting a compression of morbidity through increased physical activity:
"Active aging" connotes a radically nontraditional paradigm of aging which posits possible improvement in health despite increasing longevity. The new paradigm is based upon postponing functional declines more than mortality declines and compressing morbidity into a shorter period later in life. This paradigm (Compression of Morbidity) contrasts with the old, where increasing longevity inevitably leads to increasing morbidity.
We have focused our research on controlled longitudinal studies of aging. The Runners and Community Controls study began at age 58 in 1984 and the Health Risk Cohorts study at age 70 in 1986. We noted that disability was postponed by 14 to 16 years in vigorous exercisers compared with controls and postponed by 10 years in low-risk cohorts compared with higher risk. Mortality was also postponed, but too few persons had died for valid comparison of mortality and morbidity. With the new data presented here, age at death at 30% mortality is postponed by 7 years in Runners and age at death at 50% (median) mortality by 3.3 years compared to controls. Postponement of disability is more than double that of mortality in both studies. These differences increase over time, occur in all subgroups, and persist after statistical adjustment.