I’m an exercise procrastinator, as I’ve admitted before on this blog. Rationally I know that daily exercise will be good for me in the long run. But it’s hard to get motivated by vague health benefits that are years or even decades away.

Like any good American I like my instant gratification. I found some today in a new brain-imaging study reporting that 10 minutes of mild exercise dials up the brain’s arousal system, making you think faster and smarter.

A team of sports scientists in Japan recruited 25 healthy young people to come into the laboratory on two occasions; in one session they rode a stationary exercise bike for 10 minutes, and in the other they rested instead.

The