After Heart Attack, More Exercise Not Always Better
Excessive walking, running may lose protective effect
That finding isn't necessarily at odds with the other study, said Lavie, co-author of an editorial accompanying the studies.
"It's at least comforting to know that previously athletic, high-competition, high-level athletic activity does not seem to be associated with worsening of survival," but actually with benefits of survival, he said.
Also, the exercise done by the athletes was often not at the extreme level of marathoners, he said.
This is right in line with what heart doctors have recommended all along, said Dr. James O'Keefe, another editorial co-author and a cardiologist at St. Luke's Mid-America Heart Institute in Kansas City, Mo. "Exercise is the best thing you can do for your health," he said, if done in moderation.
"It's not good to be sedentary, but you can overdo it," he said.
Half of the U.S. population gets too little exercise, O'Keefe estimated, and "maybe one in 20 is getting too much."
According to O'Keefe, if you are exercising mostly for health (not fitness) benefits, 2.5 to 5 hours of vigorous exercise a week is plenty. He and his colleagues also noted that taking one or two days off from high-intensity exercise each week might pay off as well.