"We found that recent physical activity levels are much more important predictors of overall mortality than are distant levels of physical activity," reports a team of researchers from the University of California at Los Angeles, the Veterans Administration Medical Center in Sepulveda, California, and Boston University in Massachusetts. The researchers, led by Dr. Scott E. Sherman of the Sepulveda Veterans Administration, studied the records of 2,372 men and women from the Framingham Heart Study, which began in 1948. Participants had estimated their physical activity at assessments during two time periods: 1956-1958 and 1969-1973. For this study, the investigators looked at overall mortality and at the incidence of cardiovascular disease in the 16 years following the second evaluation. All participants were free of cardiovascular disease when the follow-up period began. The men and women who had reported being most active at the second assessment were about 39% to 42% less likely to die over the follow-up period than those who reported being least active, after age and other factors were accounted for. Activity levels reported during the distant past -- the first evaluation -- did not predict later risk of dying. Sherman's team also looked at the relationship between activity level and cardiovascular disease, but these results were not as clear. Distant activity seemed to be related to a lower rate of cardiovascular disease in men, but to a higher rate in women. "There is no obvious explanation for why this should be so," the authors note. The researchers add that this study does not provide information about how much exercise is needed to produce these benefits. They conclude, however, that "for sedentary patients, it may never be too late to start exercising."
