I don't know about you, but it's not the ticking of my biological clock that haunts my dreams, it's my circadian clock. You know, the body's complex internal timer that somehow controls our entire phyiscal and mental well-being BUT is extremely easy to screw up? By sleeping in or getting up early or staying up late or going to bed early or breathing, it seems?! Well, turns out there's yet another way you're probably maybe messing with your circadian clock. According to a recent study, the best time to exercise is in the afternoon, because early morning and late night workouts set your circadian alarm right off, and that's a bad thing (assuming you don't particularly feel like increasing your risk for "diabetes, obesity, certain types of cancer, memory loss and mood disorders, including depression.")
Granted, this theory is currently based on animal research, but I believe it. Based on my own personal ill-timed exercise experiences.