More and more of these runners have clean arteries and report having consumed more than the 200mg recommended limit of caffeine. (That is the amount in about two cups of diner coffee.) -Dr. Lewis Maharam, MD, FACSM, speaking about runners who required resuscitation and are known to have consumed excessive amounts of caffeine prior to and during marathons runningdoc.competitor.com.
MY COMMENT: I'll admit this is the first time that I've heard caffeine being linked to cardiac arrest in marathons. I do limit coffee the morning of a race, primarily because of a potential diuretic effect, however before training runs when I don't mind stopping? I probably am usually close to or over the 200 mg limit.