http://www.independent.co.uk/life-style ... 07206.html" onclick="window.open(this.href);return false;
Those who were defined as working out three times above the national guidelines – more than 450 minutes each week - had greater amounts of coronary artery calcification (CAC) over time, which is a clinical measure of the amount of calcium and plaque in the heart’s arteries.
High levels of CAC are an immediate red flag to doctors that someone is at risk of developing heart disease.
het ander onderzoek was puur statistisch en richtte zich op lopers: vanaf ongeveer 2,5 uur trainen per week wordt het risico op hartziektes gemiddeld even groot als voor wie helemaal niet sport, maar ongetwijfeld geldt dat niet voor iedereen
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"In this study, the dose of running that was most favorable for reducing mortality was jogging 1 to 2.4 hours per week, with no more than three running days per week," said study researcher Jacob Marott of the Frederiksberg Hospital in Copenhagen, Denmark. The best pace was slow or average -- about 5 miles per hour, he added. Out of a pool of about 5,000 healthy Danish adults, Marott and his colleagues followed nearly 1,100 healthy joggers and 413 sedentary people for more than 12 years. The joggers noted their hours and frequency of jogging, and their perception of their pace.
The strenuous joggers, the investigators found, were as likely to die during that time period as the sedentary non-joggers. Light joggers and moderate joggers fared better, in that order, Marott's team found.