People who stay even moderately fit as they age may live longer than those who are out-of-shape.  A study by Sandra Mandic, from University of Otago (Dunedin, New Zealand), and colleagues studied 4,384 middle-aged and older adults whose fitness levels were assessed via exercise treadmill tests between 1986 and 2006, then followed these subjects for nine years. When the researchers separated the participants into five groups based on fitness levels, they found that one-quarter of the least-fit men and women had died during the study period, as compared to 13% of those who were slightly more in-shape. Among adults in the most-fit group, only 6% died during the follow-up period.  Overall, the five groups showed little difference in their reported exercise habits over their adult lives, but there were marked differences in physical activity levels in recent years.  The team urges that: “Since it is recent physical activity that offers protection, it is important to maintain regular physical activity through life.