ultraathletes did so much better in terms of heart attack stroke risk. less than 1%. very, very low risk. jenna: as they said they asked them all the embarrassing questions you don t want to answer. exactly. i thought it was also interesting that the ultrarunners in the runners were absent from work less than american adult because accident or injury but might be for the mentality of marathon runners, because i don t need anybody s help and go to the doctors. exercise boosts immunity. when you have a better immune system that is more easily able to fight off infection you will stay healthy longer. this study is important an tells us you can train hard and live a long time with good health. jenna: it showed the younger ultramarathoners did actually worse than those doing it for years and years. right. that was the surprising start. the younger you are, the more likely you are to get injured. i think older people have enough good sense to stretch, not push themselves so hard and