On the mixed benefits of endurance training

What the new research suggests is that the benefits of running may come to a hard stop later in life. In a study involving 52,600 people followed for three decades, the runners in the group had a 19% lower death rate than nonrunners, according to the Heart editorial. But among the running cohort, those who ran a lot—more than 20 to 25 miles a week—lost that mortality advantage.

Meanwhile, according to the Heart editorial, another large study found no mortality benefit for those who ran faster than 8 miles per hour, while those who ran slower reaped significant mortality benefits.

I’m right on the bubble. What about long bike rides?