The researchers culled data for 1,098 adult men and women of varying ages who, upon their entry into the study in 2001, had identified themselves as joggers. They also had provided information about how often they ran per week, at what pace, and for how long.
The researchers also pulled records for 3,950 age-matched volunteers who had said in 2001 that they did not engage in any type of vigorous exercise or, in fact, any exercise at all.