I've read that you shouldn't exercise within three hours of bedtime, as it can keep you from getting to sleep. But, I guess it varies from person to person. I suffer from sleep apnea (used to have restless legs syndrome, too, but the paleo diet has "cured" that) and occasional insomnia (though that, too, has been greatly reduced since I've been on the diet). So, getting as much sleep as I can is especially important, as what I get is interrupted during the night. The sleep apnea has become milder, though, as a result of the diet and I believe this is because when I was losing all that fat, some of it was lost from the fatty pharyngeal tissues of my throat, which constrict my airway during sleep. As these tissues shrank in size, due to fat loss, they became less of a stricture to my airway, thus, my breathing isn't interrupted as much as it used to be.