Circadian rhythms may dictate peak workout times

[snopes]

Get up at 5 a.m., throw on some sneakers, run out the door, exercise like crazy. Sure, a pre-dawn workout comes with some bragging rights — just don't expect your best performance.

A new study suggests that late night, not early morning, is the best time to exercise, as dictated by circadian rhythms.

http://www.latimes.com/features/heal...,3917479.story