Is 4 hours okay or not ideal? Say I run at 4pm then plan to run at 8pm. What about 4 and 9? Any difference or are both too short?
Is 4 hours okay or not ideal? Say I run at 4pm then plan to run at 8pm. What about 4 and 9? Any difference or are both too short?
Yes.
Just start your run at 4pm and stop running at 8pm.
How much time between runs? After a googolplex seasons of trial and error and observation of others, I say that if the second run is the PRIMARY run, it should usually be done six to eight hours after the first run (a "shake-out") IF you intend to optimize extension of the capillary network. If you just want a warming up effect for your "real" workout of the day, you can reduce the time between runs to about four hours. If your A.M. run is the primary session, you can wait a little longer than eight hours to do your second run. You may need a few extra hours to guard against overburdening yourself if your first run was fairly taxing (in terms of length or pace or both). -John Kellogg
Any other training questions can probably be answered with this
http://www.letsrun.com/forum/flat_read.php?thread=192559&page=0
What does John Kellogg know? He makes cereal for a living.
If you run at 4 and 8, you do not have 4 hours between runs. Unless your run is 0 minutes long.