What's more important

I often read that a full nights sleep is important in any attempt in weight loss. It is also important to exercise. My question is on any particular day which one is more important. Life necessities gave me a chance of 10 minutes of exercise today. I could try to do more now or I could attempt to turn in a bit early especially as my 2 1/2 yo went to sleep an hour and half early than he usually does. As I am battling a cold, I am going to do the sleep thing, but if I weren't suffering from the cold, would exercise be more important that sleep or sleep more important the exercise, or should it go back and forth each day?