Why BlackRock's $1.7 trillion bond chief gets up at 3:30 a.m.

Rick Rieder, the chief investment officer of fixed income at BlackRock who oversees $1.7 trillion, barely sleeps and has an extremely demanding schedule. His extensive research helps inform an investment strategy that involves making a huge number of small but diversified bets. Over his 30-year career, Rieder has risen through the ranks of his many employers, all while finding time to do a good deal of charitable work. Rick Rieder thinks sleeping is a waste of time, so he wakes up at...