Is there any actual known research that dives into the following specifics of how sleep contributes to muscle growth?
Does sleep need to be consecutive hours or cycles? Meaning, does sleeping 6 hours at night, followed by a 2 hour nap have approximately the same affect as sleeping for 8 hours at night?
Most advice I have seen says something like "get 8 hours of sleep per night", but what if a lifter gets, say 6 hours of sleep the night of a lift, and then 10 hours the night after. Is there any known research that explores implications of schedules like this? Are these just averages?
It's not clear to me what role sleep plays in muscle growth vs. nutrition and lifting regimen.
I often hear about quantity of sleep. What about quality? Is 8 hours of tossing and turning inferior to 6 hours of sound sleep for muscle growth?
The reason I ask all of this is as you probably know, life is life and it's not always possible to stick to an extremely strict schedule. Family, work, and other life incidents can sometimes mix things up. These questions do not pertain to actual performance in the gym; just muscle growth (muscles physically getting larger).